American Academy of Micropigmentation

Hand Washing, Cleaning, Disinfection and Sterilization in Health Care

Date of Publication: December 1998

Volume 24S8

Canada Communicable Disease Report

ISSN 1188-4169

infection control guidelines.Our mission is to help the people of Canada

maintain and improve their health

Health Canada

This publication was produced by the Document Dissemination

Division at the Laboratory Centre for Disease Control, Health

Canada.

To obtain additional copies or subscribe to the Canada

Communicable Disease Report, please contact the Member Service

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Ottawa, ON, Canada K1G 3Y6, Tel.: 888-855-2555 or by FAX:

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This publication can also be accessed electronically via Internet

using a Web browser at http://www.hc-sc.gc.ca/hpb/lcdc.Infection Control Guidelines

Hand Washing, Cleaning,

Disinfection and Sterilization in Health Care

Health Canada

Laboratory Centre for Disease Control

Bureau of Infectious Diseases

Nosocomial and Occupational Infections.Introductory Statement

The primary objective in developing clinical

guidelines at the national level is to help health care

professionals improve the quality of health care.

Guidelines for the control of infection are needed to

assist in developing policies, procedures and evaluative

mechanisms to ensure an optimal level of care.

Guidelines facilitate the setting of standards but respect

the autonomy of each institution and recognize the

governing body’s authority and responsibility of

ensuring the quality of patient/client care provided by the

institution.

The guidelines, whenever possible, have been based

on research findings. Where there is insufficient

published research, consensus of experts in the field has

been utilized to provide guidelines specific to

conventional practice. The encouragement of research

and frequent revision and updating are necessary if

guidelines are to remain relevant and useful.

The Steering Committee acknowledges, with sincere

appreciation, the many practising health professionals

and others who contributed advice and information to

this endeavour.

The guidelines outlined herein are part of a series that

has been developed over a period of years under the

guidance of the Steering Committee on Infection Control

Guidelines. Infection Control Guidelines for Hand

Washing, Cleaning, Disinfection and Sterilization in

Health Care presents an overview and provides

recommendations to assist in preventing the transmission

of infection in health care facilities. This document is

part of the Health Canada series of Infection Control

Guidelines and is intended to be used with the other

Infection Control Guidelines, which include the

following:

Preventing the Transmission of Bloodborne Pathogens in

Health Care and Public Services Settings (1997)

Isolation and Precaution Techniques (1990) (under

revision - to be published March, 1999)

Preventing the Spread of Vancomycin-Resistant

Enterococci (1997)

Preventing the Transmission of Tuberculosis in

Canadian Health Care Facilities and Other Institutional

Settings (1996)

Canadian Contingency Plan for Viral Hemorrhagic

Fevers and Other Related Diseases (1997)

Prevention of Infections Associated with Indwelling

Intravascular Access Devices (1997)

Foot Care by Health Care Providers (1997)

Occupational Health in Health Care Facilities (1990)

(under revision)

Prevention of Nosocomial Pneumonia (1990) (under

revision)

Long Term Care Facilities (1994)

Antimicrobial Utilization in Health Care Facilities

(1990)

Prevention of Surgical Wound Infections (1990)

Prevention of Urinary Tract Infections (1990)

Perinatal Care (1988)

Organization of Infection Control Programs in Health

Care Facilities (1990)

iii.For information regarding these Health Canada

publications, contact:

Division of Nosocomial and Occupational Infections

Bureau of Infectious Diseases

Laboratory Centre for Disease Control

Health Canada, PL 0603E1

Ottawa, Ontario K1A 0L2

Telephone: (613) 952-9875

Fax: (613) 998-6413

iv.Steering Committee on Infection Control Guidelines

STEERING COMMITTEE MEMBERS

Dr. Lindsay Nicolle (Chair)

H.E. Sellers Professor and Chair

Department of Internal Medicine

University of Manitoba Health Sciences Centre

GC 430, 820 Sherbrooke Street

Winnipeg, Manitoba

R3A 1R9

Tel: (204) 787-7772

Fax: (204) 787-4826

e mail: nicolle@cc.umanitoba.ca

Dr. John Conly

Hospital Epidemiologist and Associate Professor

of Medicine

The Toronto Hospital, Room 117A-NU13

200 Elizabeth Street

Toronto, Ontario

M5G 2C4

Tel: (416) 340-4858

Fax: (416) 340-5047

e mail: jconly@torhosp.toronto.on.ca

Dr. Charles Frenette

Hôpital Charles Lemoyne

121 Taschereau Blvd.

Greenfield Park, Qc

J4V 2H1

Tel: (514) 466-5000 locale 2834

Fax: (514) 466-5778

Agnes Honish

Manager, Communicable Disease Control

Capital Health Authority

Community and Public Health

Suite 300, 10216 - 124th Street

Edmonton, Alberta

T5N 4A3

Tel: (403) 413-7944

Fax: (403) 413-7950

Dr. B. Lynn Johnston

Hospital Epidemiologist and Associate Professor

of Medicine

Queen Elizabeth II Health Sciences Centre,

Room 5-014 ACC

1278 Tower Road

Halifax, N.S.

B3H 2Y9

Tel: (902) 473-8477

Fax: (902) 473-7394

Linda Kingsbury

Nurse Consultant

Nosocomial and Occupational Infections

Bureau of Infectious Diseases, Health Canada

Laboratory Centre for Disease Control, 0603E1

Tunney’s Pasture

K1A 0L2

Tel: (613) 957-0328

Fax: (613) 998-6413

e mail: Linda_Kingsbury@hc-sc.gc.ca

Louise Meunier

Conseillère en prévention des infections

Prévention des infections

Hôpital Saint-Luc

1058 rue St. Denis

Montréal, Québec

H2X 3J4

Tel: (514) 281-3255, ext 5902

Fax: (514) 281-3293

v.Catherine Mindorff

Community and Institutional Infection Prevention

and Control

202 Yahara Place

Ancaster, Ontario

L9G 1Y5

Tel: (905) 304-1196

Fax: (905) 304-1999

Dr. Dorothy Moore

Division of Infectious Diseases

Montreal Children’s Hospital

2300 Tupper

Montréal, Québec

H3H 1P3

Tel: (514) 934-4485

Fax: (514) 934-4494

e mail: dmooinf@mch.mcgill.ca

Laurie O’Neil

Infection Prevention Consultant

4908 Nelson Rd. N.W.

Calgary, Alberta

T2K 2L9

Tel: (403) 282-2340

Shirley Paton

Chief, Nosocomial and Occupational Infections

Bureau of Infectious Diseases, Health Canada

Laboratory Centre for Disease Control, 0603E1

Ottawa, Ontario K1A 0L2

Tel: (613) 957-0326

Fax: (613) 998-6413

e mail: Shirley_Paton@hc-sc.gc.ca

Diane Phippen

Epidemiologist Nurse Coordinator

Cadham Provincial Laboratory

Box 8450, 750 William Avenue

Winnipeg, Manitoba

R3C 3Y1

Tel: (204) 945-6685 (direct line)

(204) 945-6123 (switchboard)

Fax: (204) 786-4770

LIAISON REPRESENTATIVES

Association des médecins microbiologistes

infectiologues du Québec (AMMIQ)

Dr. Charles Frenette

Association pour la prévention des infections à l’hôpital

et dans la communauté (APPI)

Yolaine Rioux, Monique Delorme

Canadian Association for Clinical Microbiology and

Infectious Diseases (CACMID)

Dr. Mary Vearncombe

Canadian Council on Health Services Accreditation

Mrs. Marilyn Colton, Assist. Executive Director

Canadian Healthcare Association

Rosa Paliotti, Barbara Lyons

Canadian Infectious Disease Society (CIDS)

Dr. Gary Garber, Dr. John Conly

The Community and Hospital Infection Control

Association - Canada (CHICA Canada)

Deborah Norton, Clare Barry

EX-OFFICIO MEMBER

Dr. John Spika

Director

Bureau of Infectious Diseases

Laboratory Centre for Disease Control, 0603E1

Health Canada

Ottawa, Ontario

K1A 0L2

Tel: (613) 957-4243

Fax: (613) 998-6413

MEMBERS OF SUBCOMMITTEE ON

HAND WASHING, CLEANING,

DISINFECTION AND STERILIZATION IN

HEALTH CARE

Agnes Honish (Chair)

Manager, Communicable Disease Control

Capital Health Authority

Community and Public Health

Suite 300, 10216 - 124 Street

Edmonton, Alberta

T5N 4A3

Tel: (403) 413-7944

Fax: (403) 413-7950

Dr. Gloria Delisle

Director, Medical Microbiology

Queen’s University

116 Brock Street

Kingston, Ontario

K7L 5G2

Tel: (613) 544-3400

Fax: (613) 531-7953

vi.Dr. Lynn Johnston

Hospital Epidemiologist and Associate Professor of

Medicine

Queen Elizabeth II Health Sciences Centre,

Room 5-014 ACC

1278 Tower Road

Halifax, Nova Scotia

B3H 2Y9

Tel: (902) 473-8477

Fax: (902) 473-7394

Linda Kingsbury

Nurse Consultant

Nosocomial and Occupational Infections

Bureau of Infectious Diseases, Health Canada

Laboratory Centre for Disease Control, 0603E1

Tunney’s Pasture

K1A 0L2

Tel: (613) 957-0328

Fax: (613) 998-6413

e mail: Linda_Kingsbury@hc-sc.gc.ca

Susan Lafferty

Infection Control Practitioner

Royal Alexandra Hospital

10240 Kingsway

Edmonton, Alberta

T5H 3V9

Tel: (413) 491-5864

Fax: (403) 491-5886

Maureen Miller

Infection Control Manager

Caritas Health Group

1100 Youville Drive, West

Edmonton, Alberta

T6L 5X8

Tel: (413) 450-7308

Fax: (403) 450-7259

Pat Piaskowski

Thunder Bay Regional Hospital

325 S. Archibald St.

Thunder Bay, Ontario

P7E 1G6

Tel: (807) 343-7123

Fax: (807) 343-7165

e mail: ppiaskow@microage-tb.com

Dr. Syed Sattar

Professor of Microbiology and Director

Centre for Research on Environmental Microbiology

Faculty of Medicine

University of Ottawa

Ottawa, Ontario

Tel: (613) 562-5800, ext. 8314

Fax: (613) 562-5452

Dr. Ann Skidmore

Medical Microbiologist

Surrey Memorial Hospital

13750 - 96th Avenue

Surrey, British Columbia

V3V 1Z2

Tel: (604) 581-2211

Fax: (604) 588-3322

The Steering Committee gratefully acknowledges the

assistance of the Editorial and Production Unit,

Document Dissemination Division, LCDC, Health

Canada, and Translation Services, Montreal.

vii.Table of Contents

HAND WASHING AND GLOVES.........................................1

A. Microbiology of the Skin ...........................................1

B. Soaps and Antiseptic Agents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

C. Waterless Hand Scrubs ............................................2

D. Hand Washing Techniques ..........................................2

Table 1. Soaps and Antimicrobial Agents for Hand Washing ...... ........ ........ 3

Table 2. Characteristics of Antiseptic Agents...... ........ ........ ........ 4

E. Compliance with Hand Washing Protocols..................................5

Table 3. How to Wash Hands ...... ........ ........ ........ ........ 5

Table 4. Proposed Strategies to Improve Hand Washing Technique and Compliance . ........ 6

Recommendations on Hand Washing ....................................6

F. Gloves .................................................8

i) Glove use..............................................8

ii) Selection of gloves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

iii) Glove types ............................................8

iv) Problems of glove use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Recommendations on Glove Use.......................................8

CLEANING, DISINFECTING AND STERILIZING PATIENT CARE EQUIPMENT ...........10

A.Classification of Medical Devices......................................10

B. Cleaning Equipment and Instruments ....................................10

Table 5. Reprocessing of Commonly Used Equipment in Health Care Settings

in Usual Situations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11

i) Sorting and soaking. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

ii) Removal of organic material ...................................12

iii) Rinsing ..............................................12

iv) Drying ..............................................13

ix.C. Disinfection ................................................13

i) Chemical disinfection ......................................13

ii) Relative resistance of microorganisms ..............................13

iii) Creutzfeldt-Jakob disease (CJD).................................13

Figure 1. Classes of Microorganisms Ranked in Descending Order from

Least to Most Susceptible to Chemical Disinfectants. ..... ........ ....... 14

Table 6. Major Classes of Chemical Disinfectants and their Relative

Advantages and Disadvantages. ...............................15

Table 7. Directions for Preparing and Using Chlorine-based Disinfectants..............17

iv) Reuse of chemical disinfectants .................................17

v) Disinfectants and safety .....................................18

vi) Registration of disinfectants in Canada .............................18

vii) Product labelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

viii) Pasteurization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

ix) Ultraviolet radiation .......................................19

x) Boiling ..............................................19

xi) Sterilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

xii) New technologies .........................................20

xiii) Monitoring of the sterilization cycle ...............................20

Table 8. Advantages and Disadvantages of Currently Available Sterilization Methods........21

xiv) Maintenance of sterility .....................................25

a. Packaging . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

b. Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

Recommendations on Cleaning, Disinfection and Sterilization.......................25

MICROBIOLOGIC SAMPLING OF ENVIRONMENT ............................27

Recommendations for Microbiologic Sampling ..............................27

HOUSEKEEPING ................................................29

A.Routine Cleaning ..............................................29

Table 9. Cleaning Procedures for Common Items...........................30

Recommendations for Routine Housekeeping ...............................31

B. Special Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

i) Special organisms of epidemiologic significance . . . . . . . . . . . . . . . . . . . . . . . . 32

ii) Blood spills ............................................32

Recommendations for Cleaning Blood Spills .............................32

iii) Surgical settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

Recommendations for Cleaning Surgical Settings ...........................32

x.LAUNDRY ................................................34

Recommendations for Laundry .......................................34

1. Collection and handling .....................................34

2. Bagging and containment.....................................35

3. Transport ...... ........ ........ ........ ........ ....... 35

4. Washing and drying .......................................35

5. Dry cleaning ...........................................36

6. Sterile linen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

7. Protection of laundry workers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

WASTE MANAGEMENT.............................................37

A. Public Health Risk. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37

Table 10. Recommendations for Management of Untreated Infectious Waste ...............38

B. Treatment of Waste ...... ........ ........ ........ ........ ....... 39

i) Chemical decontamination ....................................39

ii) Steam sterilization . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

C. Disposal Methods for Waste ........................................39

i) Landfill ....... ........ ........ ........ ........ ....... 39

ii) Sanitary sewer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

iii) Incineration. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

D. Safety for Waste Handlers. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 39

Recommendations for Waste Management.................................40

REFERENCES ................................................41

Appendix 1. Glossary .............................................52

Appendix 2. Guideline Rating System .....................................54

Table 11. Strength and Quality of Evidence for Recommendations . . . . . . . . . . . . . . . . . . . . 54

Appendix 3. Drugs Directorate Guidelines ..................................55

xi.Hand Washing and Gloves*

Disease-causing microorganisms can frequently be

isolated from the hands. Hand carriage of bacteria is an

important route of transmission of infection between

patients or from the health care worker to the

patient/client (1-6) . Appropriate hand washing results in a

reduced incidence of both nosocomial and community

infections

(1,7,8)

. Guidelines from national and inter-national

infection prevention and control organizations

have repeatedly acknowledged that hand washing is the

single most important procedure for preventing

infections

(9-11)

. Despite this, health care

providers’compliance with hand washing is poor

(12-14)

This section will review the current literature on skin

flora, antimicrobial agents used for hand antisepsis, hand

washing techniques and other aspects of hand care and

protection, and will make recommendations to be applied

in the health care setting. Routine hand washing is

discussed in this guideline, and the surgical hand scrub is

discussed in Infection Control Guidelines: Prevention of

Surgical Wound Infections

(15)

A. Microbiology of the Skin

Larson has provided an extensive review of the

physiologic and bacteriologic characteristics of the

skin (16) . The finger nail area is associated with a major

portion of the hand flora. The subungual areas (located

under the fingernail) often harbour high numbers of

microorganisms, which may serve as a source of

continued shedding, especially under gloves

(17)

Artificial nails

(18)

and chipped nail polish

(19)

may be

associated with a further increase in the number of

bacteria on fingernails.

The microbial flora of the skin consist of resident

(colonizing) and transient (contaminating) micro-organisms.

The resident microorganisms survive and

multiply on the skin. Resident flora include the

coagulase-negative staphylococci, members of the genus

Corynebacterium (diphtheroids or coryneforms),

Acinetobacter species, and occasionally members of the

Enterobacteriaceae group

(20)

. Resident skin micro-organisms

are not usually implicated in nosocomial

infections, other than minor skin infections; however,

some can cause infections after invasive procedures,

when the patient/client is severely immunocompromised

or has an implanted device, such as a heart valve or

artificial hip.

The transient microbial flora represent recent

contaminants of the hands acquired from colonized or

infected patients/clients or contaminated environment or

equipment. Transient microorganisms are not

consistently isolated from most persons. In contrast to

the resident flora, the transient microorganisms found on

the hands of health care personnel are more frequently

implicated as the source of nosocomial infections. The

most common transient flora include gram negative

coliforms and Staphylococcus aureus.

Hand washing with plain soap (detergents) is effective

in removing most transient microbial flora (20-22) . The

components of good hand washing include using an

adequate amount of soap, rubbing the hands together

to create some friction, and rinsing under running

water. The mechanical action of washing, rinsing and

drying removes most of the transient bacteria present

(23-25)

* See Appendix 1 for definitions of the following terms: antimicrobial agent, antiseptic, hand wash(ing), hand antisepsis, heavy microbial

soiling, plain or nonantimicrobial soap, sharps, surgical hand scrub..In some studies, air dryers have been shown to reduce

the number of organisms on hands after hand washing

(26-28)

Several studies have demonstrated that air hand dryers

are unsuitable for use in critical patient care areas

because of the potential for cross infection, either

through airborne dissemination or contaminated

personnel

(24,29-31)

. Air dryers may be an impediment to

hand drying because of the time taken to dry hands and

the need to ensure that the equipment is functioning.

B. Soaps and Antiseptic Agents

The purpose of hand washing is to remove soil,

organic material and transient microorganisms from the

skin. Few clinical studies have defined the absolute

indications for hand washing with plain soaps

(detergents) versus hand antisepsis with antimicrobial

products. Controlled trials have not documented

decreased infection with the use of an antiseptic agent

over plain soap for routine hand washing in the general

health care setting. The degree of reduction in microbial

numbers on the hands of health care providers necessary

to protect the recipient of care has not been defined. A

few studies have suggested that antiseptic agents may be

preferable for the care of patients if there is a possibility

of antimicrobial-resistant organisms, such as in intensive

care units

(3,32)

, in the presence of antimicrobial-resistant

organisms

(33-36)

, and under conditions of heavy microbial

soiling (e.g., in the presence of infection or a high level

of contamination with organic matter such as feces)

(37)

Understanding the distinctive ingredients and uses of

the soap and antiseptic products available is important in

choosing the appropriate agent for the appropriate

situation. If an antiseptic product is used, it should be

selected for its chemical composition, its type and

spectrum of activity, its onset and duration of activity,

the application for which it will be used, its cost,

allergenic potential and acceptability to the users.

Whatever product is used, it should be applied at the

right dilution for the recommended time with standard

methods of application.

Antiseptic hand cleansers are designed to rapidly

wash off the majority of the transient flora by their

mechanical detergent effect and to exert an additional

sustained antimicrobial activity on the resident hand flora

(Tables 1 and 2)

(38,39)

C. Waterless Hand Scrubs

Several studies have demonstrated superior efficacy of

waterless hand scrubs compared with hand washing with

soap and water or chlorhexidine

(36,47-50)

. Alcohol-based

compounds for hand antisepsis predominate in several

European countries

(51-53)

. Alcohol preparations offer

rapid reduction in microbial counts on skin

(54)

: a

vigorous, 1-minute rubbing with enough alcohol to wet

the hands completely has been shown to be an effective

method of hand antisepsis

(20,36,51,55,56)

. Alcohol

applications as short as 15 seconds in duration have been

effective in preventing hand transmission of gram-negative

bacteria (37,57) . The advantages of alcohol rubs

include the following: (1) they have an immediate and

delayed antimicrobial performance, (2) no wash basin is

necessary for their use and (3) alcohol rubs can be

conveniently available near every patient/client and are

more practical when there is insufficient time to wash

hands

(42,57,58)

. Alcohol preparations are useful in home

care when proper facilities for hand washing may be

lacking

(59)

A major disadvantage of alcohol for skin antisepsis is

its effect on the user. Waterless hand scrubs may have a

drying effect on the skin of the hands, and product

odours may be irritating for health care workers. The

addition of emollients to minimize skin drying increases

the acceptability of alcohol-based solutions on the

hands

(55)

. The antimicrobial efficacy of alcohols is

sensitive to dilution with water, therefore alcohol

preparations must be rubbed onto dry hands

(55)

. The

activity of alcohol does not appear to be significantly

affected by small amounts of blood

(60)

; however, further

studies are needed to determine activity in the presence

of large amounts of organic matter.

See Table 2 for a description of the antimicrobial

activity and uses of antiseptic agents.

D. Hand Washing Techniques

The absolute indications for and the ideal frequency of

hand washing have not been well studied. The

indications for hand washing depend on

(a) the type, intensity, duration and sequence of

activity;

(b) the degree of contamination associated with the

contact; and

recipient.

2.Table 1. Soaps and Antiseptic Agents for Hand Washing

Product Indications Special considerations

Plain soap, bar soap,

liquid*, granules

For routine care of patients/residents/clients

(10,20,40)

For washing hands soiled with dirt, blood or other organic

material

May contain very low concentrations of antimicrobial agents to

prevent microbial contamination growth in the product.

Bar soap should be on racks that allow water to drain; small bars that

can be changed frequently are safest

(11,41)

Waterless antiseptic agents:

- rinses

- foams

- wipes

- towelettes

Demonstrated alternative to conventional agents

(42)

For use where hand washing facilities are inadequate,

impractical or inaccessible (e.g., ambulances, home care, mass

immunization)

For situations in which the water supply is interrupted (e.g.,

planned disruptions, natural disasters)

Not effective if hands are soiled with dirt or heavily contaminated

with blood or other organic material.

Follow manufacturer’s recommendations for use.

Efficacy affected by concentration of alcohol in product.

Hand creams should be readily available to protect skin integrity

(43-45)

Antiseptic agents Refer to recommendations at end of this chapter.

May be chosen for hand scrubs prior to performance of invasive

procedures (e.g., placing intravascular lines or devices)

(34)

When caring for severely immunocompromised individuals

Based on risk of transmission (e.g., specific microorganisms)

Critical care areas

Intensive care nurseries

Operating room scrub

When caring for individuals with antimicrobial resistant

organisms

(33)

Antiseptic agents may be chosen if it is felt important to reduce the

number of resident flora or when the level of microbial

contamination is high.

Antiseptic agents should be chosen when persistent antimicrobial

activity on the hands is desired.

They are usually available in liquid formulations*.

Antiseptic agents differ in activity and characteristics

(38,39)

Routine use of hexachlorophene is not recommended because of

neurotoxicity and potential absorption through the skin

(46)

Alcohol containers should be stored in areas approved for flammable

materials.

* Disposable containers are preferred for liquid products. Reusable containers should be thoroughly washed and dried before refilling, and routine maintenance schedules should be followed and document ed.

Liquid products should be stored in closed containers and should not be topped-up..Table 2. Characteristics of Antiseptic Agents

Group and

subgroup

Gram-positive

bacteria

Gram-negative

bacteria

Mycobacterium

tuberculosis Fungi Virus

Speed of killing

sensitive

bacteria

Inactivated by

mucus or

proteins

Comments

Alcohols Good Good Good Good Good Fast Moderate Optimum strength 70% to 90% with added

emollients (glycerine or cetyl alcohol is less

drying), not recommended for physical cleaning

of skin; good for hand antisepsis and for surgical

site preparation.

Chlorhexidine

2% and 4%

aqueous

Good Good Fair Fair Good Intermediate Minimal Has persistent effect; good for both hand

washing and surgical site or preoperative patient

skin preparation; do not use near mucous

membranes; toxic effects on ears and eyes

reported; activity neutralized by nonionic

surfactants.

Hexachloro-

phene 3%

aqueous

Good Poor Poor Poor Poor Slow Minimal Provides persistent, cumulative activity after

repeated use (washing with alcohol reduces

persistent action), can be toxic when absorbed

from skin especially in premature infants; good

for hand washing but not for surgical site

preparation; limited spectrum of antimicrobial

activity.

Iodine

compounds,

iodine in

alcohol

Good Good Good Good Good Fast Marked Causes skin "burns," but this is unusual with 1%

tincture, especially if it is removed after several

minutes; too irritating for hand washing but

excellent for surgical site preparation.

Iodophors Good Good Fair Good Good Intermediate Moderate Less irritating to the skin than iodine; good for

both hand washing and surgical site preparation;

rapidly neutralized in presence of organic

materials such as blood or sputum

Para-chloro-

meta-xylenol

(PCMX)

Good Fair* Fair Fair Fair Intermediate Minimal Activity neutralized by nonionic surfactants

Triclosan Good Good Fair Poor Good Intermediate Minimal

*Activity improved by addition of chelating agent such as EDTA.

Note: Some of these agents, such as iodine or chlorhexidine, are combined with alcohol to form tinc tures and are available in the combined formulation (10) .

Table used with permission of author and publisher (10) ..5

Table 3. How to Wash Hands

Procedure Rationale

Remove jewelry before hand wash procedure (38,61) .

Rinse hands under warm running water. This allows for suspension and washing away of the loosened

microorganisms.

Lather with soap and, using friction, cover all surfaces of the

hands and fingers.

The minimum duration for this step is 10 seconds (25) ; more time

may be required if hands are visibly soiled.

For antiseptic agents 3-5 mL are required (38) .

Frequently missed areas are thumbs, under nails, backs of

fingers and hands.

Rinse under warm running water. To wash off microorganisms and residual hand washing agent

Dry hands thoroughly with single-use towel or forced air dryer. Drying achieves a further reduction in number of

microorganisms (24,29,38) .

Reusable towels are avoided because of the potential for

microbial contamination.

Turn off faucet without recontaminating hands. To avoid recontaminating hands.

Do not use fingernail polish or artificial nails. Artificial nails or chipped nail polish may increase bacterial

load and impede visualization of soil under nails (18,62) .

The efficacy of a hand wash depends on the time

taken and the technique. The recommended hand

washing technique is outlined in Table 3. It is important

to avoid potential microbial contamination by splashing

of clothing, other skin surfaces or inanimate items during

hand washing.

E. Compliance with Hand Washing Protocols

Although hand washing is considered the most

important single intervention for preventing nosocomial

infections

(1-6)

, studies have repeatedly shown poor

compliance with hand washing protocols by hospital

personnel

(3,12,13,63,64)

. Failure to comply is a complex

problem that includes elements of lack of motivation and

lack of knowledge about the importance of hand wash-ing.

It may also be due to real or perceived obstacles,

such as understaffing, inconveniently located hand

washing facilities, an unacceptable hand washing product

or dermatitis caused by previous hand washing. A

number of strategies have been suggested to improve

compliance (Table 4). Long-term success will require

development of programs and sustained efforts at

promoting compliance with hand washing. Effective

interventions will probably be multidimensional, and will

require the application of behavioural science theory

combined with engineering and/or product

innovation

(7,8)

..Recommendations on Hand Washing

1. Hands must be washed

(i) between direct contact with individual

patients/residents/clients;

(ii) before performing invasive procedures

(11,20)

;

(iii) before caring for patients in intensive care units

and immunocompromised patients

(11,20)

;

(iv) before preparing, handling, serving or eating

food, and before feeding a patient;

(v) when hands are visibly soiled

(13,20)

;

(vi) after situations or procedures in which

microbial or blood contamination of hands is

likely;

(vii) after removing gloves

(11,20,74)

; and

(viii) after personal body functions, such as using the

toilet or blowing one’s nose. Category B;

Grade II*

2. Hand washing should be encouraged whenever a

health care provider is in doubt about the necessity

for doing so. Category B; Grade III

Table 4. Proposed Strategies to Improve Hand Washing Technique and Compliance

Obstacle Strategy

Lack of knowledge Education with supportive literature, videotaped instructions, hand washing

demonstrations; frequent refreshers; involvement of personnel in education and

feedback (7,8,65)

Feedback on infection rates (64)

Lack of motivation Direct observation and feedback on regular basis (65) ; role models; involvement of

staff in studies; application of new technologies (63,66-69)

Programs on hand hygiene for patients and families (64,70)

Availability of hand washing facilities Hand washing facilities conveniently located throughout the health care

setting (67,68)

A sink accessible to personnel in or just outside every room; more than one sink

per room may be necessary if a large room is used for several individuals.

Hand washing facilities in or adjacent to rooms where health care procedures are

performed

Accessible, adequately supplied and proper functioning soap and towel dispensers

or hand dryers

Faucets with foot, wrist or knee operated handles; faucets with an electric eye are

also desirable.

Waterless antiseptic agents readily available in wall mounted dispensers, or in

small containers for mobile care such as home care and for emergency

responders.

Hand washing product Hand washing products that have a high level of acceptability to staff, with

appropriateness, cost, supply, etc., being taken into consideration (55,59)

Dermatitis Lotions to prevent skin dryness

Lotion supplied in small, non-refillable containers (43-45,72)

Compatibility between lotion and antiseptic products and effect on glove integrity

Lotions approved by personnel in infection control and occupational health (73)

* See Appendix 2 for the rating system used in these recommendations..3. As well as between patient/resident/client contacts,

hand washing may be indicated more than once in

the care of one person, for example after touching

excretions or secretions and before going on to

another care activity for the same person

(37)

Category B; Grade II

4. Superficial contact with an object not suspected of

being contaminated, such as when touching or

collecting food trays, generally does not require hand

washing. Category B; Grade III

5. Hand washing facilities should be conveniently

located throughout the health care setting. They

should be available in or adjacent to rooms where

health care procedures are performed. If a large room

is used for several individuals, more than one sink

may be necessary. Sinks for hand washing should be

used only for hand washing and not for any other

purpose, e.g., as a utility sink. There should be access

to adequate supplies and proper functioning soap and

towel dispensers or hand dryers, or liberal use of

waterless hand wash agents

(41,68,69)

. Category B;

Grade II

6. To avoid recontaminating hands, faucets with foot,

wrist, or knee operated handles should be installed

wherever possible; faucets with an electric eye are

also desirable. If automated faucets are not available,

single-use towels should be supplied for user to turn

off faucets. Category B; Grade III

7. Hands should be dried thoroughly with either a

single-use towel or electric air dryer (26,27) . Category

A; Grade II

8. Hand lotion may be used to prevent skin damage

from frequent hand washing

(55)

. Lotion should be

supplied in disposable bags in wall containers by

sinks or in small, non-refillable containers to avoid

product contamination. Skin lotions for patient

and/or staff use have been the reported source of

outbreaks

(43-45,72,73)

. Category B; Grade II

9. Compatibility between lotion and antiseptic products

and lotion’s potential effect on glove integrity should

be checked

(75,76)

. Category A; Grade II

10. Liquid hand wash products should be stored in closed

containers and dispensed from either disposable

containers or containers that are washed and dried

thoroughly before refilling. Category A; Grade II

11. Hand washing with plain soap is indicated in routine

health care and for washing hands soiled with dirt,

blood or other organic material. Plain soap and water

will remove many transient organisms

(20-22,40,59,77)

Category A; Grade II

12. Hand washing with an antiseptic agent is indicated

for the following situations:

(i) when there is heavy microbial soiling, e.g., in

the presence of infection or a high level of

contamination with organic matter such as

infected wounds and feces

(36,47,48,78)

. Category

A; Grade II;

(ii) prior to performing invasive procedures (e.g.,

the placement and care of intravascular

catheters, indwelling urinary catheters)

(2,5,6)

Category A; Grade I;

(iii) before contact with patients who have immune

defects, damage to the integumentary system

(e.g., wounds, burns), or percutaneous

implanted devices

(3,6)

. Category A; Grade II;

(iv) before and after direct contact with patients

who have antimicrobial-resistant

organisms

(32,35,36)

. Category A; Grade II

13. Hand washing with waterless/alcohol-based agents is

equivalent to soap and water, and these agents should

be made available where access to water is

limited (42,59,78) . If there is heavy microbial soiling,

hands must first be washed with soap and water to

remove visible soiling (20) . Hands must be dry before

an alcohol-based agent is used because moisture from

wet hands dilutes the alcohol. Category A; Grade II

14. Compliance with hand washing procedures should be

encouraged by involving users as much as possible in

product selection, facilities design, studies,

application of new technologies, education programs

and feedback

(63,64,69)

. Category A; Grade II

15.Patients/clients/residents in settings where patient

hygiene is poor should have their hands washed.

Patients/residents should be helped to wash their

hands before meals, after going to the bathroom,

before and after dialysis, and before leaving their

room. Category B; Grade III

7.F. Gloves

i) Glove use

Gloves are worn to

a. provide an additional protective barrier between

health care workers’ hands and blood, body fluids,

secretions, excretions and mucous membranes

(74,79)

and

b. reduce the potential transfer of microorganisms from

infected patients to health care workers, and from

patient to patient via health care workers’ hands

(81)

Glove use should be an adjunct to, not a substitution

for, hand washing. If hand washing is performed

carefully and appropriately by all personnel, gloves are

not necessary to prevent transient colonization of health

care workers' hands and subsequent transmission to

others

(82)

In 1987, the Laboratory Centre for Disease Control

(LCDC) recommended the use of gloves for specific

situations, primarily to protect the health care worker

from exposure to bloodborne pathogens (83) . Application

of universal precautions (82-84) significantly increased the

use of gloves in the health care setting. Some institutions

adopted body substance isolation precautions

(85)

, which

expanded the use of gloves to prevent contamination of

hands.

ii) Selection of gloves

It is important to assess and select the most

appropriate glove to be worn for the circumstances.

Selection of gloves should be based on a risk analysis of

the type of setting, type of procedure, likelihood of

exposure to blood or fluid capable of transmitting

pathogens, length of use and amount of stress on the

glove

(86)

. Factors such as personal comfort and fit, cost

and latex allergy in employees and clients/residents are

also important considerations.

iii) Glove types

Non-sterile gloves sold in Canada must meet the

requirements of Health Canada Information Letter No.

777 (April 30, 1990). Health Canada recommends

purchasing gloves with the Canadian General Standards

Board certification mark, which ensures that voluntary

national standards are met during manufacturing.

However some types of glove materials are not available

in certified brands. The Medical Devices Bureau of

Health Canada has an information package on glove

quality and certification, and on latex allergy (1-800-

267-9675)

(87)

Studies have demonstrated varying effectiveness of

gloves as barrier protection. Some studies have

concluded that latex gloves were associated with less

leakage than vinyl gloves

(74,88-92)

. Other studies have

shown non-latex gloves to be effective

(79,93-96)

iv) Problems of glove use

Constant use of gloves may cause irritant dermatitis.

The cause of the dermatitis may be mechanical irritation

from the glove or glove powder; it may also be chemical

agents, such as residual soap, trapped between the glove

and skin.

Latex allergy is an increasing concern in health care

settings because of the potentially serious outcomes in

workers and clients who are allergic to latex. Some

employees affected by latex allergy may be able to work

in an area where others are using low protein, non-powdered

latex gloves. Employees and clients who are

severely allergic to latex need to avoid all contact with it.

For further information on latex allergy in health care

facilities, refer to the Canadian Healthcare Association

publication Guidelines for the Management of Latex

Allergy and Safe Latex Use in Health Care Facilities

(97)

Recommendations on Glove Use

For further information and recommendations on

glove use, refer to Health Canada’s Infection Control

Guidelines Preventing the Transmission of Bloodborne

Pathogens in Health Care and Public Services

Settings

(84)

and the revision of Health Canada’s Isolation

and Precaution Techniques

(98)

1. Gloves should be used as an additional measure, not

as a substitute for hand washing

(74,99)

. Category B:

Grade II

2. Gloves are not required for routine patient care

activities if contact is limited to a patient's intact skin,

e.g., when transporting patients. Category B;

Grade III

3. Gloves may not be needed for routine diaper changes

if the procedure can be done without contaminating

the hands with stool or urine. Category C

4. Clean non-sterile gloves should be worn

(i) if exposure is anticipated to blood and body

fluids capable of transmitting bloodborne

infection

(84)

(ii) if exposure is anticipated to potentially

infectious material such as pus, feces,

8.respiratory secretions or exudate of skin

lesions

(81,85)

(iii) when the health care worker has non-intact skin

on his or her hands. Category A; Grade II

5. Sterile gloves must be worn for procedures in which

the hands or the instruments being handled are

entering a sterile body cavity or tissue (2,100) .

Category A; Grade I

6. The accepted standard should be that medical gloves

be worn for all blood collection procedures.

However, if phlebotomists choose not to wear gloves

routinely, they must be gloved for perfoming

phlebotomy if they have cuts, scratches or other

breaks in their skin, or when hand contamination

with blood is anticipated. All students or new

trainees must wear medical gloves during their

training period and in subsequent blood collection

procedures

(84)

7. Worn gloves should be changed

(i) between patient/client/resident contacts,

(ii) if a leak is suspected or the glove tears,

(iii) between care activities and procedures on the

same patient after contact with materials that

may contain high concentrations of micro-organisms

(e.g., after manipulating an

indwelling urinary catheter and before

suctioning an endotrachial tube) (74,88). .

Category A; Grade II

8. Hands must be washed after gloves are

removed

(74,86,89,91)

. Category A; Grade II

9. Potentially contaminated gloves should be removed

prior to touching clean environmental surfaces (e.g.,

lamps, blood pressure cuffs)

(74,101)

. Category A;

Grade II

10.Single-use disposable gloves should not be washed

or reused. Category A; Grade II

11. Disposable, good quality medical gloves made of

vinyl, nitrile, neoprene or polyethylene serve as

adequate barriers, particulary when latex allergies are

a concern. Category A; Grade II

The Health and Safety Act requires that employers

provide appropriate personal protective apparatus

(102)

They should make suitable gloves available to

employees to prevent the transmission of infection to

residents/clients/patients. Employees should assess

the risk in each procedure, choose gloves that are

appropriate to the task, and recommend alternative

gloves if the ones available are not adequate

(84,86)

The following is suggested as a guide.

(i) If latex gloves are chosen, low protein and

unpowdered gloves should be selected.

(ii) Non-latex gloves should be available for

individuals with latex sensitivity.

(iii) Vinyl gloves should be used for short tasks or

for tasks in which there is minimal stress to

glove material.

(iv) For housekeeping activities, instrument

cleaning and decontamination procedures,

general purpose reusable household gloves

(e.g., neoprene, rubber, butyl) are recom-mended.

Medical gloves are not durable

enough for these activities.

9.Cleaning, Disinfecting and Sterilizing

Patient Care Equipment*

Appropriate cleaning, disinfection and sterilization of

patient care equipment are important in limiting the

transmission of organisms related to reusable patient care

equipment. Decisions concerning the appropriate

processes, methods or products are complex, given the

many types and compositions of medical devices and the

great variety and combination of cleaning, disinfection

and sterilization methods available

(103-108)

The reprocessing method required for a specific item

will depend on the item’s intended use, the risk of

infection to the patient, and the amount of soiling

(59,109-111)

Cleaning is always essential prior to disinfection or

sterilization. An item that has not been cleaned

cannot be assuredly disinfected or sterilized. See

Table 5 for examples.

A. Classification of Medical Devices

In the 1970s, E.H. Spaulding developed a system to

classify the cleaning, disinfection and sterilization

requirements for equipment used in patient/client care.

This system divides medical devices, equipment and

surgical materials into three categories based on the

potential risk of infection involved in their use

(117)

. The

three categories are noncritical, semicritical, and critical.

The categories are defined in the glossary at the end of

this document.

B. Cleaning Equipment and Instruments

Cleaning is an extremely important part of

equipment and instrument reprocessing and is

necessary to permit maximum efficacy of subsequent

disinfection and sterilization treatments.

Effective cleaning can physically remove large

numbers of microorganisms (118) . Soil or other foreign

materials can shield microorganisms and protect them

from the action of disinfectants or sterilants or interact

with the disinfectant or sterilant to neutralize the activity

of the process

(119-122)

. Organic material left on a medical

device is extremely difficult to remove after treatment

with glutaraldehyde, which acts as a fixative.

Manufacturers must provide detailed directions for

effective cleaning of all reusable products. The method

and effectiveness of cleaning an item must be considered

prior to purchase. Do not purchase products that cannot

be cleaned. If such products are purchased the health care

setting has the responsibility to develop detailed cleaning

procedures. Effective reprocessing requires rigorous

compliance with recommended protocols. Even full

compliance with protocols may be insufficient if the

method or product selected is inadequate or inappropriate

for cleaning and subsequent disinfection or sterilization

of a particular device.

Staff responsible for cleaning contaminated health

care equipment must be properly trained and conversant

with the purpose of their task. They should wear personal

protective equipment appropriate to the task to protect

themselves from exposure to potential pathogens and

chemicals and to protect the integrity of their skin.

Employees should also be immunized against hepatitis B

(84)

* See Appendix 1 for definitions of the following items: noncritical items, semicritical items, criti cal items, biofilm, cleaning,

decontamination, disinfection, germicides, low level disinfection, intermediate level disinfection, high level disinfection, sanitation,

sterilization..11

Table 5. Reprocessing of Commonly Used Equipment in Health Care Settings in Usual Situations

(See the section on Housekeeping for routine environmental cleaning; outbreaks may require

special disinfection measures)

MANUFACTURERS’ RECOMMENDATIONS FOR CONCENTRATION AND EXPOSURE TIME MUST BE FOLLOWED.

Process Equipment Examples of items* Products or methods†

Cleaning

Some items may

require low level

disinfection ‡

All reusable

equipment

All reusable equipment, since such

equipment requires cleaning after use and

before further disinfection processes are

initiated

Certain environmental surfaces (e.g., of

dental lamps) touched by personnel during

procedures involving parenteral or mucous

membrane contact

Bedpans, urinals, commodes

Stethoscopes

Blood pressure cuffs

Ear specula

Hemodialysis surfaces in contact with

dialysate

Physical removal of soil, dust or foreign

material. Chemical, thermal or mechanical

aids may be used.

Cleaning usually involves soap and water,

detergents or enzymatic agents.

Quaternary ammonium compounds

Phenolics should not be used in nurseries

Some iodophors

3% hydrogen peroxide

Cleaning

followed by

intermediate level

disinfection ‡

Some

semicritical

items

After large environmental blood spills or

spills of microbial cultures in the laboratory

Glass thermometers

Electronic thermometers

Hydrotherapy tanks used for patients whose

skin is not intact ‡

Alcohols

Hypochlorite solutions

Iodophors

Phenolics should not be used in nurseries.

Cleaning

followed by high

level disinfection

Semicritical

items

Flexible endoscopes ‡

Laryngoscopes ‡

Respiratory therapy equipmenta ‡

Nebulizer cups ‡

Anesthesia equipment ‡

Endotrachial tubes ‡

Nasal specula

Tonometer foot plate ‡

Ear syringe nozzles

Vaginal specula

Vaginal probes used in sonographic

scanning ‡

Pessary and diaphragm fitting rings ‡

Cervical caps

Breast pump accessories

Items intended for sterilization in the plasma

or EO sterilizers must be meticulously

cleaned prior to sterilizing (112) .

Pasteurization (113)

2% glutaraldehyde

6% hydrogen peroxide

Peracetic acid

Chlorine or chlorine compounds

* For products that appear in two categories, manufacturers’ directions differ for length of exposure time and concentration.

† Manufacturers' recommendations for concentration and exposure time must be followed.

‡ For guidelines regarding disinfection, refer to comprehensive discussion of disinfection issues (110,114-116) ..i) Sorting and soaking

Unless they can be cleaned immediately, instruments

and small items should be sorted and then submerged in

water and/or detergent to prevent the organic matter from

drying on them. Complete disassembly of each item is

necessary to allow effective cleaning. Heavy or nonim-mersible

items should be wrapped in or covered with a

wet towel.

ii) Removal of organic material

Removal is done with the use of detergents, enzymatic

cleaners, or elevated temperature with or without the use

of mechanical devices such as washer-sterilizer, ultra-sonic

cleaner, dishwasher, utensil washer or washer-disinfectors.

A detergent is used to reduce surface

tension and suspend the soil in water. The detergent

selected must be compatible with the subse quent dis-infection

process because some products can interfere

with chemical disinfection or sterilization. An enzymatic

solution may be used to help in the removal of protein-

aceous material when plain water and/or a detergent

solution is considered inadequate. Combination low level

disinfectant-detergent products (also referred to as

germicidal detergents) are frequently used to clean items

that do not require further disinfection or sterilization

(e.g., intravenous [IV] poles, commodes, wheelchairs).

iii) Rinsing

A thorough rinsing is necessary to remove all the soil

and cleaning agent from the items, to avoid spotting and

to ensure thorough cleanliness. Depending upon the

quality of the available water supply, the final rinse may

require distilled or de-ionized water

(119)

. Cleaning agents

(i.e., detergents) may also make surfaces slippery or

leave residuals that impair equipment integrity and

function. When cleaning is to be followed by

disinfection, it must be ensured that residuals of the

cleaning agent are removed to prevent neutralization of

the disinfectant (120,123) .

Process Equipment Examples of items* Products or methods†

Cleaning

followed by

sterilization

Critical items All items contacting sterile tissue

Surgical instruments

All implantable devices

Needles and syringes

Cardiac and urinary catheters

Hemodialysis, plasmapheresis and heart-lung

oxygenator surfaces in contact with blood

All intravascular devices

Biopsy forceps or biopsy equipment

associated with endoscopy equipment

Bronchoscopes ‡

Arthroscopes ‡

Laparoscopes ‡

Cystoscopes ‡

Transfer forceps

Acupuncture needles and body piercing

objects

Neurologic test needles

Arterial pressure transducers ‡

High speed dental handpieces

All instruments used for footcare

Steam under pressure

Dry heat

Ethylene oxide gas

2% glutaraldehyde

6-25 % hydrogen peroxide

Peracetic acid

Chlorine dioxide

6-8% formaldehyde

* For products that appear in two categories, manufacturers’ directions differ for length of exposure time and concentration.

† Manufacturers' recommendations for concentration and exposure time must be followed.

‡ For guidelines regarding disinfection, refer to comprehensive discussion of disinfection issues (110,114-116) ..iv) Drying

Drying prevents microbial growth. All items that

require no further treatment must be dried prior to

storage. Immediate drying is necessary to prevent

corrosion of stainless steel equipment. While they are

drying, the items should be inspected to ensure that they

are free of all organic soil, oil, grease, and other

matter

(124)

. Post-disinfection flushing of endoscopes with

70% alcohol to ensure thorough drying prior to storage

has been recommended

(118)

Bacteria grow attached to surfaces because of their

hydrophobicity (insolubility in water)

(119,125)

. When

nonsterile surfaces are moist or continuously wet, they

may become coated with a "biofilm", which is a layer of

bacteria encased in an extracellular substance. Biofilm

and its bacteria can be released when disrupted (e.g., in

the lumens of endoscopes). Biofilm development may

also protect bacteria from subsequent disinfection or

sterilization.

Items that require further disinfection or sterilization

may also need to be dried, as water may dilute the action

of the chemical disinfectant.

C. Disinfection

Disinfection is required when cleaning processes

alone do not render an item safe for its intended use.

There are three major methods of disinfection: liquid

chemicals, pasteurization and ultraviolet radiation.

Failure to use disinfection products or processes

appropriately has repeatedly been associated with the

transmission of nosocomial infections

(117,126, 127)

. Table 5

shows the cleaning and disinfection levels required for

many commonly used items of equipment.

In health care settings, the precise nature of the

microbial burden may not be known. In the natural

environment, microorganisms are usually found in

mixtures. For example, fecal material contains vegetative

as well as spore forms of bacteria along with fungi,

viruses and protozoa. Therefore, products and procedures

selected to disinfect instruments must be known to be

effective against pathogens with varying levels of

resistance (See Figure 1). The level of disinfection

achieved depends on factors such as contact time,

temperature, extent of soil, type and concentration of the

active ingredients of the chemical disinfectant, and the

nature of the microbial contamination

(121,126,128)

A variety of factors influence the efficacy of

disinfectant processes, including the innate resistance of

the microorganisms (Figure 1), the concentration and

type of organic and inorganic material present

(cleanliness, presence of biofilm), the intensity and

duration of the treatment, the concentration (on initial

and repeated use) of the disinfectant, the temperature

associated with the process, the contact time associated

with the process, the pH of the solution, the hardness of

water used as the diluent, and interfering residues that

may remain after cleaning

(126,128, 129)

i) Chemical disinfection

In Canada, chemical disinfectants used in health care

settings are regulated by the Health Protection Branch of

Health Canada (see the discussion of Registration of

Disinfectants in Canada later in this section).

ii) Relative resistance of microorganisms

Microorganisms have variable susceptibility to

disinfectant agents (see Fi gure 1). Vegetative bacteria

and enveloped viruses are usually the most sensitive, and

bacterial spores and protozoan cysts the most resistant.

Some pathogens (e.g., Pseudomonas aeruginosa) have

been shown to be significantly more resistant than

their laboratory grown counterparts to a variety of

disinfectants in their "naturally occurring" state,

(i.e., in body fluids and tissues) (110) .

Major classes of disinfectant chemicals and their

relative advantages and disadvantages are summarized in

Table 6. The manufacturer of the chemical disinfectant

will provide instructions for use, including the

recommended exposure time. Manufacturers’

recommendations regarding exposure time must be

followed.

iii) Creutzfeldt-Jakob Disease (CJD)

The Laboratory Centre for Disease Control is

developing CJD protocols

(134,135)

. The prion that causes

Creutzfeldt-Jakob resists normal inactivation methods.

Human infection with the CJD agent has resulted from

either direct exposure of the brain to the CJD agent (e.g.,

dura mater graft) or peripheral injection of CJD agent-contaminated

product derived from human brain

(pituitary hormone). Special CJD-specific infection

control precautions are recommended for patients who

have developed, are suspected of having developed, or

are at substantially increased risk of developing CJD

(i.e., persons who have received human pituitary

hormone [growth hormone and gonadotrophin] or dura

mater grafts, or members of a family in which CJD is

recognized as being familial)

(135)

Needles, needle electrodes, scalpels, ophthalmic

tonometers, autopsy instruments, dedicated equipment

cryostats and all other potentially contaminated materials

should be sterilized by special procedures.

13.Figure 1.

Classes of Microorganisms Ranked in Descending Order from Least to Most Susceptible to Chemical Dis infectants

Least susceptible

Most susceptible

BACTERIA WITH SPORES

(Bacillus subtilis, Clostridium tetani, C. difficile

C. botulinum)

PROTOZOA WITH CYSTS

(Giardia lamblia, Cryptosporidium parvum)

MYCOBACTERIA NON-ENVELOPED VIRUSES

(Mycobacterium tuberculosis (Coxsackieviruses, polioviruses,

M. avium-intracellulare, M. chelonae) rhinoviruses, rotaviruses,

Norwalk virus, hepatitis A virus)

VEGETATIVE BACTERIA

(Staphylococcus aureus, Salmonella typhi, Pseudomonas aeruginosa,

coliforms)

ENVELOPED VIRUSES

(Herpes simplex, varicella-zoster virus, cytomegalovirus, Epstein-Barr

virus, measles virus, mumps virus, rubella virus, influenza

virus, respiratory syncytial virus, hepatitis B and C viruses,

hantaviruses, and human immunodeficiency virus)

FUNGI

(Candida species, Cryptococcus species, Aspergillus species, Dermatophytes).15

Table 6. Major Classes of Chemical Disinfectants and their Relative Advantages and

Disadvantages

MANUFACTURERS’ RECOMMENDATIONS FOR CONCENTRATION AND EXPOSURE TIME MUST BE FOLLOWED.

Disinfectant Uses Advantages Disadvantages

Alcohols Intermediate level disinfectant

Disinfect thermometers, external

surfaces of some equipment (e.g.,

stethoscopes).

Equipment used for home health care (59)

Used as a skin antiseptic

Fast acting

No residue

Non staining

Volatile

Evaporation may diminish

concentration

Inactivated by organic material

May harden rubber or cause

deterioration of glues

Use in the OR is contraindicated

Chlorines (131) Intermediate level disinfectant

Disinfect hydrotherapy tanks, dialysis

equipment, cardiopulmonary training

manikins, environmental surfaces.

Effective disinfectant following blood

spills; aqueous solutions (5,000 parts

per million) used to decontaminate area

after blood has been removed; sodium

dichloroisocyanurate powder sprinkled

directly on blood spills for

decontamination and subsequent

cleanup.

Equipment used for home health

care (59)

See Table 7 for uses for and dilution of

chlorines.

Low cost

Fast acting

Readily available in

non hospital settings

Corrosive to metals

Inactivated by organic material

Irritant to skin and mucous membranes

Unstable when diluted to usable state

(1:9 parts water)

Use in well-ventilated areas

Shelf life shortens when diluted

Ethylene oxide Used as gas for the sterilization of heat

sensitive medical devices

Sterilant for heat or

pressure sensitive

equipment

Slow acting and requires several hours

of aeration to remove residue. One of

its carriers (chlorofluorocarbon) is now

a restricted chemical.

Formaldehyde Very limited use as chemisterilant

Sometimes used to reprocess

hemodialyzers

Gaseous form used to decontaminate

laboratory safety cabinets

Active in presence of

organic materials

Carcinogenic

Toxic

Strong irritant

Pungent odour

Glutaraldehydes 2% formulations — high level

disinfection for heat sensitive

equipment

Most commonly used for endoscopes,

respiratory therapy equipment and

anesthesia equipment

Noncorrosive to metal

Active in presence of

organic material

Compatible with

lensed instruments

Sterilization may be

accomplished in 6-10

hours

Extremely irritating to skin and mucous

membranes

Shelf life shortens when diluted

(effective for 14-30 days depending on

formulation)

High cost

Monitor concentration in reusable

solutions

Fixative.16

Disinfectant Uses Advantages Disadvantages

Hydrogen

peroxide

3% — low level disinfectant

Equipment used for home health care (59)

Cleans floors, walls and furnishings

6% — high level disinfectant

Effective for high level disinfection of

flexible endoscopes (132)

Foot care equipment

Disinfection of soft contact lenses

Higher concentrations used as

chemisterilants in specially designed

machines for decontamination of heat

sensitive medical devices

Strong oxidant

Fast acting

Breaks down into

water and oxygen

Can be corrosive to aluminum, copper,

brass or zinc

Iodophors Intermediate level disinfectant for some

equipment (hydrotherapy tanks,

thermometers)

Low level disinfectant for hard

surfaces and equipment that does not

touch mucous membranes (e.g., IV

poles, wheelchairs, beds, call bells)

Rapid action

Relatively free of

toxicity and irritancy

Note: Antiseptic iodophors are NOT

suitable for use as hard surface

disinfectant

Corrosive to metal unless combined

with inhibitors

Disinfectant may burn tissue

Inactivated by organic materials

May stain fabrics and synthetic

materials

Peracetic acid High level disinfectant or sterilant for

heat sensitive equipment

Higher concentrations used as

chemisterilants in specially designed

machines for decontamination of heat

sensitive medical devices

Innocuous

decomposition (water,

oxygen, acetic acid,

hydrogen peroxide)

Rapid action at low

temperature

Active in presence of

organic materials

Can be corrosive

Unstable when diluted

Phenolics Low/intermediate level disinfectants

Clean floors, walls and furnishings

Clean hard surfaces and equipment that

does not touch mucous membranes

(e.g., IV poles, wheelchairs, beds, call

bells)

Leaves residual film

on environmental

surfaces

Commercially

available with added

detergents to provide

one-step cleaning and

disinfecting

Do not use in nurseries

Not recommended for use on food

contact surfaces

May be absorbed through skin or by

rubber

Some synthetic flooring may become

sticky with repetitive use

Quaternary

ammonium

compounds

Low level disinfectant

Clean floors, walls and furnishings

Clean blood spills (133)

Generally non-

irritating to hands

Usually have detergent

properties

DO NOT use to disinfect instruments

Non-corrosive

Limited use as disinfectant because of

narrow microbicidal spectrum.iv) Reuse of chemical disinfectants

Several physical and chemical factors influence

disinfectant action, including temperature, pH, relative

humidity, and water hardness (110,128) . Extremes of acidity

or alkalinity can effectively limit growth of micro-organisms.

Moreover, the activity of antimicrobial agents

may be profoundly influenced by relatively small

changes in the pH of the medium

(136)

. An increase in pH

improves the antimicrobial activity of some disinfectants

(e.g., glutaraldehyde, quaternary ammonium compounds)

but decreases the antimicrobial activity of others (e.g.,

phenols, hypochlorites, iodine). The pH influences the

antimicrobial activity by altering the disinfectant

molecule or the cell surface

(110)

Many chemical disinfectants require dilution prior to

use. It is mandatory that users follow exactly the

manufacturer’s directions regarding dilution and mixing.

If the concentration of the disinfectant is too low the

efficacy will be decreased. If the concentration is too

high the risk of the chemical damaging the instrument or

causing toxic effects on the user increases.

Once diluted some disinfectants may be used (if

handled properly) for a period of days or weeks.

Dilutions are inherently unstable once mixed and the

manufacturer’s directions as to duration of use must be

followed.

Glutaraldehydes require special discussion. Glutar-aldehydes

may be in acidic or alkaline formulations, and

are usually purchased in concentrated forms and diluted

for use. These dilutions are time limited. During reuse,

the concentration of active ingredient(s) in the product

may drop as dilution of the product occurs (incomplete

drying), and while organic impurities accumulate

(incomplete cleaning)

(128)

. Chemical test strips are

available for determining whether an effective

concentration of active ingredients (e.g., glutaraldehyde)

is present despite repeated use and dilution. The

frequency of testing should be based on how frequently

the solutions are used (e.g., used daily, test daily). The

strips should not be considered a way of extending the

use of a disinfectant solution beyond the expiration date.

The glutaraldehyde solution should be considered unsafe

Table 7. Directions for Preparing and Using Chlorine-based Disinfectants

Product Intended use Recommended dilution Level of available chlorine

Household bleach

(5% sodium hypochlorite

solution with 50,000 ppm *

available chlorine)

Cleanup of blood spills Use concentrations ranging

from 1 part of bleach to be

mixed with 99 parts of tap

water (1:100) or one part of

bleach to be mixed with 9

parts of tap water (1:10),

depending on the amount of

organic material (e.g., blood or

mucus) present on the surface

to be cleaned and disinfected.

0.05% or 500 ppm

0.5% or 5,000 ppm

To add to laundry water One part (one 8 ounce cup) of

bleach to be mixed with about

500 parts (28 gallons†) of tap

water

0.01% or 100 ppm

Surface cleaning

Soaking of glassware or

plastic items

One part (one 8 ounce cup) to

be mixed with about 50 parts

(2.8 gallons) of tap water

0.1% or 1,000 ppm

NaDCC (Sodium dichloro-isocya

nurate) powder with

60% available chlorine

Cleanup of blood spills Dissolve 8.5 g in one litre of

tap water

0.85% or 5,000 ppm

Chloramine-T powder with

25% available chlorine

Cleanup of blood spills Dissolve 20 g in one litre of

tap water

2.0% or 5,000 ppm

* Parts per million

† Imperial gallon (4.5 litres)

For further information on uses of bleach in health care refer to article on subject

(131)

..when the concentration of glutaraldehyde falls below the

minimum effective concentration (MEC) for the product

or the dilution falls below 1% glutaraldehyde

(110)

v) Disinfectants and safety

Chemical disinfectants are a double-edged sword.

Although their use is necessary in many routine health

care settings, the ability of these products to kill

infectious agents also makes them potentially harmful to

humans and the environment. Although manufacturers

continue to work to improve their formulations, it is

unrealistic to expect that highly effective disinfectants

that are also completely safe will be available in the near

future.

Products containing glutaraldehyde require special

attention. Glutaraldehydes are used exten sively in the

disinfection of semicritical instruments because they are

noncorrosive and relatively fast acting in addition to

possessing a broad spectrum of activity. However, the

pungent and irritating nature of glutaraldehyde fumes

and the toxic effects of this disinfectant on skin make it a

workplace hazard. The expanding use of glutaraldehyde

in many health care settings has led to legislation or

regulations in some provinces (e.g., British Columbia)

that limit workers’ exposure to glutaraldehyde fumes, for

instance through the installation of fume hoods and

extraction fans in units using glutaraldehyde.

vi) Registration of disinfectants in Canada

In Canada, the main control of antimicrobials rests on

two pieces of legislation. Antimicrobial products that are

labelled for use in health care facilities or food

processing plants or on medical devices and are

produced for the purposes of disease prevention and

health preservation are regulated as drugs under the Food

and Drugs Act and Regulations, which are administered

by the Therapeutic Products Programme, Bureau of

Pharmaceutical Assessment, Health Protection Branch,

Health Canada. Products used for disinfection or

antimicrobial purposes in domestic or household

applications, non-food industrial applications, etc. are

regulated under the Pest Control Products Act and

Regulations, which are administered by the Pest

Management Regulatory Agency, Health Canada.

For disinfectant drugs, manufacturers must obtain a

drug identification number (DIN) from Health Canada

prior to marketing. To obtain this they must submit a

DIN application, with labelling and supporting data (if

required) to the Therapeutic Products Directorate for

evaluation. For a DIN to be issued, it must be established

that the product is effective and safe for its intended

use

(137)

The extent of premarket assessment of disinfectant

products is based on the relative risk associated with the

use of the product, which varies depending on the

established knowledge of the active ingredients and the

proposed uses for the product. On the basis of this

premise, disinfectants or sterilants for use on medical

instruments undergo a more rigorous pre-market

assessment than disinfectants containing well-known

active ingredients for use on environmental surfaces such

as floors and walls.

Specific efficacy test methodologies and data

requirements for disinfectants to be marketed in Canada

are recommended by the Canadian General Standards

Board. These requirements vary according to the

proposed use(s) of the product, resulting in specific test

methodologies and test organisms to match specific

claims of efficacy. The most stringent requirements exist

for sterilants, products that are to be used for the

sterilization of critical instruments. High level

disinfectants carry less stringent requirements and are

labelled for use on semicritical instruments. Low level

disinfectants are labelled for the disinfection of

noncritical items and environmental surfaces, and thus

have the least stringent efficacy requirements.

The label on the disinfectant must clearly indicate the

following information: the product name, a quantitative

statement of active ingredient(s), its intended use, the

area and site of use, and specific directions for use,

including the specific types of surfaces/instruments to be

disinfected, any dilution procedure required, the mode of

application, the contact time, any cleaning and rinsing

procedures, the temperature for use and the reuse period.

The labelling must also include appropriate pre-cautionary

symbols and statements as well as first aid

instruction.

The proposed label claims are reviewed, and in order

to be considered acceptable they must have been

substantiated with data demonstrating with a great level

of confidence that the product is effective under the

proposed conditions of use. The label claims must not be

misleading.

Should there be any questions regarding the label

claims, conditions of use, etc., of a product, the

reviewing bureau within the Health Protection Branch

(Bureau of Pharmaceutical Assessment) should be

contacted for verification. See Appendix 3 for

information.

18.vii) Product labelling

• The product label must have a Drug Identification

Number (DIN). The presence of a DIN indicates that,

upon review, it has been established that the product is

safe and effective for its intended use.

• The prod uct la bel must be read care fully for in struc -tions

on use. Fail ure to do so of ten leads to in appro -priate

use, stor age or dis posal of the prod uct and may

expose the pa tient as well as the health care worker

to an in creased risk of in fections or toxic chemi cal

effects. In appropriate stor age of chemi cal dis infec -tants

may re duce their shelf life, and if they be come

contaminated, may also lead to bac terial growth.

• The product label should include mixing instructions,

including concentrations for dilution, and length of

disinfection time.

• The prod uct label needs to be read for fac tors that may

influence the activ ity of the dis infectant, such as tem -perature,

pH, rela tive humid ity and water hard ness.

viii) Pasteurization

Pasteurization is a process of hot water disinfection,

which is accomplished through the use of automated

pasteurizers or washer disinfectors. Semicritical items

suitable for pasteurization include equipment for

respiratory therapy and anesthesia.

Exposing respiratory and anesthesia equipment to

water above 75

C for 30 minutes is a recognized

alternative to chemical disinfection. Items to be

pasteurized must be thoroughly cleaned with detergent

and water prior to disinfection

(109)

. The items must be

totally immersed in water during the pasteurization

cycle.

The advantages of pasteurization include its

nontoxicity, rapid disinfection cycle, and moderate cost

of machinery and upkeep.

The major disadvantages of pasteurization are that

(1) it is not sporicidal, (2) it may cause splash burns,

(3) there is a lack of standardization of the equipment

and (4) there is difficulty validating the effectiveness

of the process. The process may be monitored by

temperature gauges and timing mechanisms.

Since pas teurization is not a ster ilization pro cess,

extreme care must be taken to en sure that the pro cess is

appropriately per formed so that in fectious agents consid -ered

to be par ticularly im portant are in activated

(138)

. Af ter

pasteurization, spe cial care must be taken to dry (re sidual

water tends to col lect) and pre vent re contamination of

the equip ment dur ing stor age and trans port

(138,139)

ix) Ultraviolet radiation

Microorganisms are inactivated by ultraviolet (UV)

light in wavelengths within a range of 250-280 nm

(140)

Modern mercury-vapor lamps emit radiation within that

level. Ultraviolet radiation has several potential appli-cations,

but its germicidal effectiveness and use is

influenced by organic matter, wavelength, type of

suspension, temperature, type of microorganism, and UV

intensity (which is affected by distance and dirty tubes).

The application of UV light in the hospital is limited to

the destruction of airborne organisms or inactivation of

microorganisms located on surfaces. Ultraviolet

germicidal irradiation is a method of air cleaning that can

be used to supplement other tuberculosis control

measures. Installing ultraviolet lamps in ventilation ducts

has two advantages: high levels of UV irradiation may be

produced and, since the UV light is in the duct, the risk

of human exposure is reduced or eliminated (141) . The

Health Canada Guidelines for Preventing the Trans-mission

of Tuberculosis in Canadian Health Care

Facilities and Other Institutional Settings

(140)

concludes

its discussion of UV germicidal irradiation by saying that

it may be a useful adjunct in ventilation ducts or in high-risk

areas, such as bronchoscopy suites, autopsy suites,

or other areas where patients with undiagnosed TB may

be seen frequently.

No data support the use of UV lamps in isolation

rooms

(110)

. Portable ultraviolet light devices should not

be used for disinfection purposes in community settings

(e.g., of esthetic or body piercing equipment).

UV light may cause skin and eye burns, and may

theoretically cause cataracts and skin cancer. Problems

have occurred when UV lights have not been installed

properly or have not been monitored and maintained

correctly

(139,140)

x) Boiling

Boiling is not an acceptable method of sterilization in

health care. In home care, boiling has been used to

disinfect some items if they do not deteriorate in the pro -cess.

Home care guidelines should be followed

(59,142,143)

The use of boiling water to clean instruments and

utensils cannot be called sterilization. Research has

shown that boiling water or moist heat at a temperature

of 100 0 C (212 0 F) is inadequate for the destruction of

bacterial spores and some viruses (144) . Another major

disadvantage of using boiling water to clean instruments

and utensils is that the items are not packaged so that

they can be stored and transported without

contamination.

19.xi) Sterilization

All critical items that are in contact with the blood

stream, nonintact mucous membranes or normally sterile

body sites must be sterile. Sterilization is a process, not

just a single event. Appropriate procedures must be

followed to achieve and maintain sterility. The sterili-zation

process must be validated and documented.

Table 8 summarizes the advantages and disadvantages

of sterilization methods as well as recommended appli-cations

and monitoring strategies. Manufacturers of

sterilizers should be contacted for specific instructions on

installation and use of their equipment. Storage and

transportation practices must maintain sterility to the

point of use. Manufacturers of sterilizers should be

specific as to which devices can be sterilized in their

machines, and manufacturers of medical devices and

equipment should be specific as to the recommended

sterilization methods.

xii) New technologies

Because of difficulties in disinfecting and sterilizing

equipment, such as heat-labile medical devices and

devices with small lumens, new technologies are being

developed. New technologies will have limited appli-cations

(e.g., may not be appropriate for instruments with

lumens or may be incompatible with some materials). No

single method will work for all hospitals. Policies and

procedures must be established to ensure that the

reprocessing of equipment follows the principles of

infection prevention.

There is controversy about the monitoring of the

efficacy of liquid chemical sterilization cycles. Biologic

monitoring of liquid chemical sterilization processes

using traditional biologic indicators does not appear

feasible at this time

(154)

xiii) Monitoring of the sterilization cycle

Monitoring of sterilization cycles can be divided into

three distinct methods

(139)

Mechanical: time and temperature graphs, charts

or printouts

Chemical: time/temperature and/or humidity

sensitive tape, strips or pellets

(155)

Biologic: spore-laden strips or vials

(156)

Mechanical and chemical monitors merely provide a

visible indicator that the conditions required to achieve

sterilization, such as time, temperature and pressure,

have been met.

Only biologic indicators monitor the actual

effectiveness of the sterilization process, which is

intended to kill all microbes, including spores

(157)

. An

ideal biologic indicator should have the following

characteristics: a well characterized organism, widely

available, standardized preparation, more resistant to the

sterilization process than human pathogens, rapid

readout, easy to use, nonpathogenic, and inexpensive (158) .

The spores chosen for biologic monitoring must be

appropriate for the method of sterilization being

monitored

(154)

. For example Bacillus stearothermophilus

spores are used for steam sterilization and Bacillus

subtilis for dry heat and ethylene oxide cycles. The

frequency of monitoring is indicated in Table 8.

Traditionally, commercially prepared biologic

indicators require an incubation time of 24 to 48 hours

prior to reading. The recent development of rapid readout

biologic monitors, which use fluorometric detection of a

spore-bound enzyme at 60 minutes, may offer an

alternative to observation of spore growth. Use of rapid

readout biologic indicators may enable release of

sterilized implants for use or rapid recall of inadequately

sterilized devices

(156,157)

. The manufacturer’s instructions

should be followed in the use of all commercially

prepared biologic monitoring systems.

Although indicators are an important part of quality

assurance of sterilization processes, the validation of the

process and documentation of the operating parameters

of the process are of paramount importance. Testing with

spore and chemical indicators is only as good as the

placement of the spore suspensions or indicators. All

sterilization processes should be thoroughly evaluated

before being put into service, and at regular intervals

afterwards. Autoclaves should be mapped with

thermocouples to determine potential cold spots. Filter

systems should be tested for leakage. Gas sterilization

units should be appropriately validated for such factors

as gas concentration, temperature, and relative humidity.

In order to ensure appropriate sterilization processes,

health care facility personnel must comply with the

manufacturer’s recommendations.

The daily operation of the sterilization must be

documented by personnel performing the process. This

documentation should be reviewed for each operation,

and any malfunction should be noted and appropriate

action taken to ensure that the product either has been

properly treated or is returned for reprocessing

(138)

The health care facility should have a protocol on the

procedure to follow if monitoring shows equipment

failure

(139)

20.Table 8. Advantages and Disadvantages of Currently Available Sterilization Methods

MANUFACTURERS’ RECOMMENDATIONS FOR CONCENTRATION AND EXPOSURE TIME MUST BE FOLLOWED.

Sterilization method Parameters Monitoring/frequency Use/advantages Disadvantages

Steam

a) Small table top sterilizers

b) Gravity displacement

sterilizers including flash

sterilizers

c) High-speed vacuum sterilizers

Flash sterilization

Raised pressure (preset by

manufacturer) to increase

temperature to 121 0 C (133 0 C for

flash sterilizers)

Time varies with temperature,

type of material and whether the

instrument is wrapped or not.

Steam must be saturated (narrow

lumen items may require

prehumidification).

Flash sterilization should be

used only in an emergency.

Flash sterilization should never

be used for implantable devices.

Air detection for vacuum

sterilizers - daily before first

cycle of day

Mechanical - each cycle (103)

Chemical - each cycle (103)

Biologic - at least weekly, but

preferably daily, and with each

load of implantable items

(Bacillus stearotherm ophilus

spores). Loads containing

implantable devices shall be

monitored and, whenever

possible, the implantable devices

quarantined until the results of

the biologic indicator testing are

available (103) .

Mechanical - each cycle

Chemical - each cycle

Biologic - at least once a week

but preferably daily (145)

Heat tolerant instruments and

accessories

Linen

Inexpensive

Rapid

Efficient

Non toxic

Can be used to sterilize liquids

Not recommended

Unsuitable for anhydrous oils,

powders, lensed instruments, heat

and moisture sensitive materials.

Some table top sterilizers lack a

drying cycle.

If the devices are used before the

results of biologic indicators are

known, personnel must record

which devices were used for

specific patients, so that they can

be followed if the load was not

processed properly (113,145-148) .

Difficult to monitor

The efficacy of flash sterilization

will be impaired if all the

necessary parameters are not met

properly (e.g., time, temper-ature),

the device is contaminated

with organic matter, air is

trapped in or around the device,

or the sterilizer or flash pack is

not working properly.

Sterility cannot be maintained if

the device is not wrapped..Sterilization method Parameters Monitoring/frequency Use/advantages Disadvantages

Ethylene oxide gas (EtO) EtO concentration based on

manufacturer's recommendation

Temperature - variable

Humidity 50%

Time - extended processing time

(several hours)

Mechanical - each cycle (105)

Chemical - each cycle (105)

Biologic - each cycle (105)

(Bacillus subtilis spores)

Heat sensitive items

Not harmful to heat sensitive and

lensed instruments

Expensive

EtO systems have been changed

because of the elimination of

CFCs (149) .

Toxic to humans

Environmental hazard when

combined with chlorinated

fluorocarbons

Requires monitoring of residual

gas levels in environment

Requires aeration of sterilized

products prior to use

Lengthy cycle required to

achieve sterilization and aeration

Highly flammable and explosive,

and highly reactive with other

chemicals

Causes structural damage to

some devices

Dry heat

a) Gravity convection

b) Mechanical convection

Temperatures - time

171 0 C - 60 min

160 0 C - 120 min

149 0 C - 150 min

141 0 C - 180 min

121 0 C - 12 hours

Mechanical - each cycle

Chemical - each cycle

Biologic - weekly (139)

(Bacillus subtilis spores)

Anhydrous oil

Powders

Glass

No corrosive or rusting effect on

instruments

Reaches surfaces of instruments

that cannot be disassembled

Inexpensive

Lengthy cycle due to slowness of

heating and penetration

High temperatures may be

deleterious to material.

Limited packing materials

Temperature and exposure times

vary, depending on article being

sterilized (139) .

Glutaraldehyde Time and temperature must be

maintained.

Sterilized items must be rinsed

with sterile water (116,119) .

Sterilized items must be handled

in a manner that prevents

contamination from process

through storage to use.

None for sterility

Monitors available for pH and

dilution concentration

Heat sensitive items Unable to monitor sterilization

Handling provides opportunities

for contamination.

Copious rinsing with sterile

water required to remove all

residual disinfectant at

termination of cycle.

Toxicity of chemicals to health

care workers and environment

Lengthy process (6-12 hours)..Sterilization method Parameters Monitoring/frequency Use/advantages Disadvantages

Boiling Not recommended None Not recommended May be used for dedicated

equipment for clients receiving

home care (e.g., catheters used by

one person) (59,142,143)

Microwave ovens Not recommended None Not recommended Unable to monitor

Unreliable method (150)

Home use microwaves unable to

achieve sterilization (150)

Glass bead sterilizers Not recommended None Not recommended Unable to monitor

Cold spots

Inconsistent heating

Trapped air (151)

Hydrogen peroxide vapour Time and temperature controlled

by cycle

Follow manufacturer’s instruc -tions

Spores of Bacillus

stearothermophilus are used as

biologic indicators.

Heat sensitive items, e.g.,

endoscopes

Noncorrosive due to short contact

times required

Environmentally friendly

byproducts

Low toxicity if devices are

aerated (152)

Limited field trials on efficacy of

sterilization

Inactivation by highly absorptive

materials such as cellulose paper

and linen, thus limiting

packaging material

Inability to enter deeply into

small lumens (153)

Further evaluation of toxicity is

required (152) .

Hydrogen peroxide

a) liquid (6-25%)

b) gas plasma

Time and temperature controlled

by cycle

Follow manufacturer’s

instruc tions

Heat sensitive items e.g.,

endoscopes

Can be applied to metal and non-metal

as well as heat and

moisture sensitive instruments

Rapid

Nontoxic

Lack of corrosion to metals and

other materials (except nylon)

Limitations on length and lumens

of devices that can be effectively

sterilized (112,153)

With gas plasma, inactivation of

hydrogen peroxide by highly

absorptive materials (linen,

cellulose paper) (153).Sterilization method Parameters Monitoring/frequency Use/advantages Disadvantages

Peracetic acid Time and temperature controlled

by cycle

Follow manufacturer’s

instruc tions

Heat sensitive immersible items

e.g., endoscopes, surgical

instruments

Rapid

Automated

Leaves no residue

Effective in presence of organic

matter

Sporicidal at low temperatures

Monitoring of efficacy of

sterilization cycle with spore

strips is questionable (154)

Can be used for immersible

instruments only

Corrosive

Material incompatibility with

some materials

Unstable particularly when

diluted

In vapour form, PAA is volatile,

has a pungent odour, is toxic, and

is a fire and explosion hazard.

Combination systems of

peracetic acid vapour with

mixture of hydrogen, oxygen and

inert carri er

Time and temperature vary by

cycle

Follow manufacturer’s

instructions

Heat sensitive items

Dialysers

Rapid

Nontoxic

Combination system is less

corrosive than peracetic acid

alone

Limited field trials on efficacy of

sterilization

Each type of machine needs to be

independently verified for

effectiveness.xiv) Maintenace of sterility

a. Packaging

When the process permits, items to be sterilized

should be packaged in appropriate wraps before

sterilization. One of the main disadvantages of liquid

chemical sterilization is that the items are not wrapped

before sterilization yet must be stored and transported in

a way that minimizes contamination. Ideally, the selected

packaging material should possess the following

characteristics: it should allow for adequate air removal,

sterilant penetration and evacuation; act as a barrier to

microorganisms or their vehicles (e.g., dust, vermin)

after sterilization is complete; show temperature

stability; be strong enough to withstand normal handling;

be flexible to permit sealing, wrapping and unwrapping;

allow for aseptic removal of sterilized product; produce

minimal linting; contain no toxic ingredients or non fast

dyes; and maintain seal integrity without resealing upon

opening. In the case of rigid containers, gasket integrity

must be proven

(103,105,108)

b. Storage

Sterilized items — those sterilized in the health care

setting and those purchased as sterile — must be stored

in a protected area where products are unlikely to

become exposed to moisture, dirt, dust or vermin. Shelf

life is event related

(103)

. Event-related shelf life practice

recognizes that the product should remain sterile until

some event causes the item to become contaminated

(e.g., a tear in packaging, packaging becomes wet, or

dropped)

(160)

. Event-related factors include frequency and

method of handling, and storage area conditions such as

appropriate location, space, open/closed shelving,

temperature and humidity, and freedom from dust,

insects, flooding, and vermin (138,160) .

Items purchased as sterile must be used before the

expiration date if one is given. Culture should be done

only if clinical circumstances suggest infection related to

the use of the item. If intrinsic contamination is sus-pected,

notify the Bureau of Radiation and Medical

Devices, Health Protection Branch, Health Canada, and

local and provincial health departments.

Single-use sterile items that are opened but not used

may be able to be re-sterilized. However, it is necessary

to ensure that the product can withstand the sterilization

method chosen, and that this method will achieve

sterilization of the device. The Canadian Healthcare

Association has identified principles for the reuse of

single-use medical devices and various activities that

should be considered in the sterilization procedure

(162)

Recommendations on Cleaning, Disinfection and

Sterilization

Each health care setting should have a protocol for

reprocessing and maintenance of sterility.

1. Items that are received sterile must be maintained

sterile until use

(139,163,164)

. Category A; Grade II

2. Reusable items must be thoroughly cleaned before

disinfection or sterilization

(110,120)

. Category A;

Grade II

3. Reusable items must be adequately rinsed and dried

before disinfection or sterilization

(119)

and dried

before storage. Category A; Grade II

4. Manufacturers’ written recommendations for use of

chemical disinfectant should be followed.

5. Only disinfectants with a DIN should be used

(disinfectants approved for use in Canada).

6. Respiratory therapy and anesthetic equipment require,

at a minimum, high level disinfection

(113,165-167)

7. Critical items must be sterile

(110)

. Category A;

Grade III

8. Semicritical items should be disinfected as detailed

in Table 5

(116,139)

. Category A; Grade III

9. The sterilization process must be monitored by

biologic indicator testing:

– for steam sterilizers: at least weekly, but

preferably daily. Loads containing implantable

devices shall be monitored and, whenever

possible, the implantable devices quarantined

until the results of the biologic indicator testing

are available (103) .

– for ethylene oxide sterilizers: every load that is

to be sterilized (105) .

– for dry heat sterilization: at least weekly

(139)

Category A; Grade III

10. The sterilization process must be monitored at each

cycle by mechanical and chemical indicators

(139)

Category A; Grade III

11. After reprocessing, sterility should be maintained

until point of use

(139)

. Category A; Grade III

25.12. If a health care facility reuses a single-use medical

device, an established protocol must be established

and followed to ensure a level of safety, following

the framework of the Canadian Healthcare

Association

(162)

13. A procedure for recall of items processed from a load

that contained a positive biologic indicator should be

established by the institution (103,105) . Category A;

Grade III

14. Flash sterilization is not recommended and should be

used only in an emergency, and never for implantable

devices. Category D; Grade III

15. Microwave ovens, glass bead sterilizers and boiling

for sterilization should not be used

(144)

. Category D;

Grade III

16. A specially trained, knowledgable person must be

responsible for the disinfection and sterilization

process. Category B; Grade III

26.Microbiologic Sampling of Environment

The results of microbiologic sampling have seldom

been useful in directing infection prevention and control

programs. Before 1970, routine environmental culturing

of inanimate objects was a widely practised infection

control surveillance activity in hospitals. However,

nosocomial infection rates have seldom been associated

with documented colony counts on cultures of air or

environmental surfaces where reasonable hygiene exists.

Meaningful standards for permissible levels of microbial

contamination of the environment do not exist

(168)

. By

1988, LCDC strongly recommended that routine

culturing of floors, walls, linen, air and infant formula be

discontinued

(71)

However, microbiologic sampling may be indicated in

selected circumstances, such as an outbreak or other

unusual increase in nosocomial infection transmission in

which environmental reservoirs are implicated. Such

culturing should be based on epidemiologic data and

must follow a written plan that specifies the objects to be

sampled and the actions to be taken, based on culture

results

(169)

One major exception to the recommendations to avoid

routine spot checking is related to routine sampling of all

water and dialysate fluid after dialysis. Gram negative

bacteria have the ability to multiply rapidly in water and

other fluids associated with the hemodialysis system.

These fluids do not need to be sterile, but excessive

levels of gram negative bacterial contamination have

been associated with numerous pyrogenic and

bacteremic reactions

(170)

. A quantitative guideline for

interpretation of levels of contamination has been

proposed

(115,170-173)

The issue of microbiologic sampling of hydrotherapy

pools and tanks is controversial. These tanks have been

associated with infections. Health care settings that use

hydrotherapy pools and tanks may wish to conduct

microbiologic sampling as a quality indicator that

cleaning and water treatment methods are adequate.

Recommendations for Microbiologic Sampling

1. Routine culturing of air, environmental surfaces or

medical devices, either on a scheduled or periodic

basis, is not recommended. Category E; Grade II

2. Routine microbiologic sampling of patient care items

purchased as sterile is not recommended. Category

D; Grade III

3. Routine sampling of the water and dialysate fluid

after dialysis is recommended. Category A;

Grade II

(a) Dialysate water used to prepare dialysate fluid

should be checked microbiologically once a

month. The level of contamination should not

exceed 200 cfu/mL

(174-177)

(b) Endotoxin contamination in dialysate water used

to rinse and reprocess dialysers, and water used

to prepare dialyser disinfectant should not

exceed 1 ng (5 endotoxin units [EU])/mL (178,179) .

at the end of the dialysis treatment. The level of

bacterial contamination should not exceed 2,000

cfu/mL. Machine water should be taken from

different machines to ensure random

sampling

(174-177)

4. In an outbreak, selective environmental

microbiologic sampling may be indicated. Sampling

should be obtained from the potential environmental

sites implicated in the epidemiologic investigation, as

suggested by the outbreak organism(s) or patient

27.characteristics, (e.g., when clusters of infections

occur in patients following endoscopy procedures

with possible implication of the equipment, then

endoscopes should be sampled)

(119)

. Category A;

Grade II

5. If contamination of a commercial product sold as

sterile is suspected, infection control personnel

should be notified, suspect lot numbers should be

recorded, and items from suspected lots should be

segregated and quarantined. Appropriate

microbiologic assays may be considered. The

Medical Devices Bureau, Environmental Health

Directorate, Health Protection Branch, Health

Canada, provincial health authorities, and

manufacturers should be notified promptly.

Category A; Grade III

28.Housekeeping*

Although microorganisms are ubiquitous in health

care settings, inanimate materials are seldom responsible

for the direct spread of infections. Cleaning and

maintenance prevent the build-up of soil, dust or other

foreign material that can harbour pathogens and support

their growth

(180)

. Although there is virtually no risk of

transmitting infectious agents to patients by way of the

inanimate environment, soiled items could contribute to

secondary transmission by contaminating hands of health

care workers or by contact with medical equipment that

will subsequently come in contact with patients.

Skin antiseptics, except alcohol, should not be used

for cleaning inanimate objects.

Cleaning is accomplished with water, detergents and

mechanical action. Cleaning reduces or eliminates the

reservoirs of potential pathogenic organisms.

Detergents are adequate for most housekeeping

(59)

Disinfectants are not usually needed in housekeeping

activities in health care settings, but are necessary in

specified areas (e.g., surgical suites, ICUs, transplant

units, surfaces of dialysis machines). Refer to Table 9 for

indications on the use of a disinfectant. Disinfection is

accomplished by liquid or powdered chemicals. Levels of

chemical disinfection vary with the type of product used (128) .

A. Routine Cleaning

The aim of cleaning is to achieve a clean environment

with regular and conscientious general housekeeping.

Extraordinary measures do not need to be taken to

disinfect the health care environment

(115)

; high level

disinfection and sterilization are not used in house-keeping

activities. Visible dust and dirt should be removed

routinely with water and detergent and/or vacuuming (181) .

Duct, fan and air conditioning systems should be cleaned

and maintained according to a schedule.

The environment should be kept free of clutter to

facilitate housekeeping.

The most frequent source of infection from the

inanimate environment is contaminated equipment.

Decontamination of patient care equipment is discussed

on pages 10-26.

However, environmental water reservoirs have been

associated with numerous infections and outbreaks.

Examples include faucet aerators, shower heads, sinks,

drains, flower vase water, ice machines, water carafes

and hydrotherapy baths

(115,173)

. Housekeeping protocols

should include careful cleaning of wet surfaces and

equipment to prevent the build-up of biofilms.

Hands play a major role in the transmission of human

pathogenic microorganisms to susceptible hosts. Hands

can acquire known or potential pathogens by contact

with objects and animate and inanimate surfaces.

Strict adherence to hand washing recommendations

(see pages 6-7) is more likely to prevent infections

than procedures exceeding routine cleaning of the

environment.

Housekeeping issues concerning the inanimate

environment and the transmission of disease may be

summarized as follows:

Prevent objects heavily contaminated with organic

material from coming into close contact with portals of

entry into the body. For example, patients with non-intact

skin, such as those with burns or surgical incisions,

*See Appendix 1 for definitions of the following terms: antiseptics, cleaning, disinfection, fomite s, sanitation..would be susceptible to infection if exposed to patient

care equipment contaminated with feces. Ensure

contaminated environmental surfaces are clean to prevent

the hands of health care workers or patients/residents/

clients from becoming contaminated (25) .

Ensure that contaminated inanimate environments do

not contaminate patients/clients/residents through contact

with mucous membranes. The transmission of viral and

other infections can be reduced by effective cleaning of

environmental surfaces

(101)

. During casual contact,

transfer of infectious agents from contaminated surfaces

to clean surfaces can readily occur

(101)

, and upon

inoculation (contaminated hands touching eyes, mouth,

other mucous membranes, etc.) could lead to trans-mission

(182)

. For example, volunteers in a study infected

themselves with respiratory syncytial virus (RSV) after

handling objects from the room of an RSV-infected

patient and then touching their noses and mouths

(115)

Many human pathogens can remain viable on porous

and nonporous inanimate objects from several hours to

several days (25,129) . Laboratory-based investigations have

clearly demonstrated that the spread of many types of

infectious agents can be successfully interrupted by their

proper cleaning and, when necessary, disinfection

(101)

The frequency of cleaning and disinfecting the health

care environment may vary according to the type of

surface to be cleaned, the number of people and amount

of activity in the area, the risk to patients and the amount

of soiling. Horizontal surfaces have a higher number of

organisms than vertical surfaces, ceilings and smooth

intact walls.

Table 9. Cleaning Procedures for Common Items

Frequency of cleaning will depend on care setting. In acute care settings equipment should be clean ed between patients.

In community settings the frequency of cleaning has not been determined.

Surface/object Procedure Special considerations

Horizontal surfaces such as over bed

tables, work counters, baby weigh scales,

beds, cribs, mattresses, bedrails, call bells

1. Thorough regular cleaning

2. Cleaning when soiled

3. Cleaning between patients/clients and

after discharge

Special procedures sometimes called

carbolizing are not necessary.

Some environmental surfaces may

require low level disinfection (e.g., in

nurseries, pediatric settings, critical care,

burn units, emergency rooms, operating

rooms and bone marrow transplantation

facilities).

Walls, blinds, curtains Should be cleaned regularly with a

detergent and as splashes/visible soil occur.

Floors 1. Thorough regular cleaning

2. Cleaning when soiled

3. Cleaning between patients/clients

and after discharge.

Damp mopping preferred

Detergent is adequate in most areas.

Blood/body fluid spills should be cleaned

up with disposable cloths followed by

disinfection with a low level disinfectant.

Carpets/upholstery Should be vacuumed regularly and

shampooed as necessary.

Toys Should be regularly cleaned, disinfected

with a low level disinfectant, thoroughly

rinsed, and dried (between patients in

acute care setting).

For pediatric settings, toys should be

constructed of smooth, nonporous (i.e.,

not plush) materials to facilitate cleaning

and decontamination.

Do not use phenolics.

Toilets and commodes 1. Thorough regular cleaning

2. Cleaning when soiled

3. Clean between patients/clients

and after discharge.

Use a low level disinfectant.

These may be the source of enteric

pathogens such as C. difficile and

Shigella (173) ..For noncritical devices that have contact only with

intact skin (e.g., beds, handrails, IV poles, wheelchairs)

and for most large environmental surfaces with which

humans have little direct contact (e.g., floors, walls,

furnishings) routine cleaning is sufficient (Table 9)

(139)

This can usually be achieved with water and a detergent.

Some environmental surfaces that are frequently

touched by health care providers and/or patients, such as

call bell lights, surfaces of medical equipment and

knobs/handles for adjustment or opening, have greater

potential as vehicles for infectious agents. Therefore,

careful attention should be paid to the regular cleaning of

environmental surfaces that are frequently touched.

For further information on cleaning after the discharge

of a patient for whom Contact Precautions have been

necessary, refer to Health Canada's Revision of Isolation

and Precaution Techniques

(98)

Recommendations for Routine Housekeeping

1. Routine cleaning of environmental surfaces and

noncritical patient care items should be performed

according to a predetermined schedule and should

be sufficient to keep surfaces clean and dust

free

(115,180,183)

. Surfaces that are frequently touched by

the hands of health care providers and clients, such as

call bells, surfaces of medical equipment and knobs

for adjustment or opening, require frequent cleaning.

Category B; Grade III

2. Careful mechanical cleaning of environmental

surfaces is effective in removing many contaminants

from surfaces. Category A; Grade II

3. Health care facilities should determine a schedule for

cleaning and maintaining ducts, fans, and air

conditioning systems

(115)

. Category A; Grade II

4. An education program for housekeeping staff should

help them to understand the effective methods of

cleaning and the importance of their work. Category

B; Grade III

5. Damp rather than dry dusting or sweeping should be

performed whenever possible. Any dry cleaning

should be done carefully with a chemically treated

dry mop or vacuum cleaner (equipped with exhaust

filter) rather than a broom. Category B; Grade III

6. Vacuum cleaners should be used on carpeted areas.

Expelled air from vacuum cleaners should be

diffused so that it does not aerosolize dust from

uncleaned surfaces. Category B; Grade III

7. During wet cleaning, cleaning solutions and the tools

with which they are applied soon become contamin-ated.

Therefore, a routine should be adopted that does

not redistribute microorganisms. This may be accom-plished

by cleaning less heavily contaminated areas

first and changing cleaning solutions and cloths/mops

frequently. Category B; Grade III

8. Wet mopping is most commonly done with a double-bucket

technique, which extends the life of the

solution because fewer changes are required. When a

single bucket is used, the solution must be changed

more frequently because of increased bioload.

Category B; Grade III

9. Tools used for cleaning and disinfecting must be

cleaned and dried between uses. Category B;

Grade III

10. Mop heads should be laundered daily in areas of

great activity and at a set interval for areas of lesser

contamination. All washed mop heads must be dried

thoroughly before storage

(115)

. Category B;

Grade III

11. Cleaning agents: a detergent is acceptable for

surface cleaning in most areas (Table 9). A low or

intermediate grade disinfectant, often called a

germicidal detergent

(128)

(see Tables 6 and 7 for

examples), may be preferable for cleaning in

nurseries, pediatric settings, critical care, burn units,

emergency rooms, operating rooms, bone marrow

transplantation facilities, and surfaces of dialysis

machines. Category B; Grade III

12. Phenolics should not be used in nurseries (See

Tables 6 and 7). Category A; Grade II

13. Cleaning and disinfecting agents must be mixed and

used according to manufacturers’ recommendations.

Category A; Grade III

14. Protective apparatus: household utility gloves should

be worn during cleaning and disinfecting procedures.

Manufacturers’ directions should be followed for

product use to ensure safe handling practices.

Category B; Grade III

15. Disinfectant fogging should not be done

(184)

Category D; Grade III

16. Health care facilities should develop policies for

cleaning schedules and methods, which should

include the name of the person who is responsible for

housekeeping. Category A; Grade III

31.B. Special Cleaning

i) Special organisms of epidemiologic significance

Except during outbreaks, no special environmental

cleaning techniques are advocated for organisms such

as Clostridium difficile, methicillin-resistant Staphylo-coccus

aureus or vancomycin-resistant enterococci

(115,185)

During an outbreak, thorough environmental cleaning

and disinfection with a disinfectant that has demonstrated

effectiveness against the specific organism may be

required

(186,187)

ii) Blood spills

(84)

Note: Some recommendations are not graded for

strength of evidence because they are from previous

Infection Control Guidelines, which were not graded.

Recommendations for Cleaning Blood Spills

1. Appropriate personal protective equipment should be

worn for cleaning up a blood spill. Gloves should be

worn during the cleaning and disinfecting pro-cedures.

If the possibility of splashing exists, the

worker should wear a face shield and gown. For large

blood spills, overalls, gowns or aprons as well as

boots or protective shoe covers should be worn.

Personal protective equipment should be changed if

torn or soiled, and always removed before leaving the

location of the spill, then hands washed.

2. The blood spill area must be cleaned of obvious

organic material before applying a disinfectant, as

hypochlorites and other disinfectants are substantially

inactivated by blood and other materials

(84,109,117)

3. Excess blood and fluid capable of transmitting

infection should be removed with disposable towels.

Discard the towels in a plastic-lined waste

receptacle.

4. After cleaning, the area should be disinfected with a

low level chemical disinfectant (e.g., chemical

germicides approved for use as "hospital dis-infectants",

such as quaternary ammonium

compounds) or sodium hypochlorite (household

bleach). Concentrations ranging from approximately

500 ppm (1:100 dilution of household bleach)

sodium hypochlorite to 5000 ppm (1:10 dilution of

household bleach) are effective, depending on the

amount of organic material (e.g., blood or mucus)

present on the surface to be cleaned and disinfected.

See Table 7 for directions on the preparation and use

of chlorine-based disinfectants. Commercially

available chemical disinfectants may be more

compatible with certain medical devices that might

be corroded by repeated exposure to sodium

hypochlorite, especially the 1:10 dilution

(59,109,133)

Manufacturers' recommendations for dilutions and

temperatures of chemical disinfectants approved for

use as hospital disinfectants must be followed.

5. For carpet or upholstered surfaces a low level

disinfectant may be used. For home health care, a

common supermarket disinfectant may be used.

6. Previous recommendations have suggested that

sodium hypochlorite or chemical germicide should

be left on the surface for 10 minutes.

7. The treated area should then be wiped with paper

towels soaked in tap water. Allow the area to dry.

8. The towels should be discarded in a plastic lined

waste receptacle.

9. Care must be taken to avoid splashing or generating

aerosols during the clean up.

10. Hands must be thoroughly washed after gloves are

removed.

11. For blood spills in clinical, public health or research

laboratories, refer to recommendations for

laboratories

(188,189)

iii) Surgical settings (modified from Association of

Operating Room Nurses (190-192) )

Recommendations for Cleaning Surgical Settings

For the purposes of this discussion, surgical settings

include the operating room, ambulatory surgical

units

(148)

, physicians' offices where invasive procedures

are done, intravascular catheterization laboratories,

endoscopy rooms and all other areas where invasive

procedures may be performed.

1. Cleaning procedures should be completed on a

scheduled basis, usually daily.

2. Areas outside the sterile field contaminated by

organic debris should be cleaned as spills or splashes

occur.

3. Surgical lights and horizontal surfaces, equipment,

furniture and patient transport vehicles should be

cleaned between patients with a clean cloth and a low

level disinfectant.

4. Floors should be cleaned with a low level

disinfectant/detergent, preferably using a wet vacuum

32.system between patients

(139)

or, depending on type of

procedures carried out, at the end of the day.

5. Counter tops and surfaces that have been

contaminated with blood or body fluids capable of

transmitting infection should be cleaned with

disposable towelling, using an appropriate cleaning

agent and water as necessary, (e.g., after each

procedure, after treatment of each patient/client, at

the completion of daily work activities, and after any

spill). Surfaces should then be disinfected with a

low-level chemical disinfectant or sodium

hypochlorite. Loose or cracked work surfaces should

be replaced

(84)

6. All other areas and equipment in the surgical practice

setting, (e.g., air conditioning grills and/or filters,

cabinets, shelves, walls, ceilings, lounges and locker

rooms) should be cleaned according to an established

routine.

7. Before any piece of portable equipment enters or

leaves the operating room, it should be wiped with

the approved disinfectant.

33.Laundry

The potential for transmission of infection from soiled

linen is negligible (115,172,193-195) . In fact, there are only a

handful of reports suggesting soiled linen as a cause of

cross infection. In these studies, there were suspected

sources of infection other than the soiled linen (115,172,193) .

When appropriate precautions are followed by care

givers and laundry workers for collecting, transporting,

handling, washing, and drying soiled linen, the risk of

cross infection can be virtually eliminated

(172,193)

All linen that is soiled with blood, body fluids,

secretions or excretions or contaminated with lice or

scabies should be handled using the same precautions,

regardless of source or care setting

(40,115,172,193,196-201)

. If

the bag soaks through, an additional outer bag should be

used. Recent studies show that the practice of "double

bagging" linen from isolation areas or when contam-ination

with certain bacteria or viruses is suspected is not

only costly but also unnecessary

(172,193,195,202)

Microbial counts on soiled linens are significantly

reduced during the mechanical action and dilution of

washing and rinsing. With the high cost of energy and

use of cold water detergents (which do not require heat

to catalyze their actions) hot water washes (>71.1º C for

25 minutes) may not be necessary. Several studies show

that low temperature laundering will effectively

eliminate residual bacteria to a level comparable with

high temper ature laundering

(172,193,195)

. When low

temperature washes are combined with the addi tion of

bleach (with a total available residual chlorine of 50-150

ppm), residual bacteria on laundry are re duced to below

levels found on laundry washed at high tempera-tures

(172,193)

. See Table 7 for directions on preparing and

using chlorine-based disinfectants. Machine drying of

linen contributes to a further reduction of residual

bacteria

(172,193)

Easily laundered clothing should be provided for

residents in group facilities or long-term care facilities to

avoid the use of garments (e.g., of silk or wool) requiring

dry cleaning or other special handling.

The presence of sharps in soiled linens has caused

sharps injuries in laundry workers. A needle tracking

system may be effective in reducing the number of

sharps found in soiled laundry. This approach establishes

a system of feedback to personnel deemed responsible

for the sharps debris.

Recommendations for Laundry

1. Collection and handling

a. All soiled linen from health care facilities should be

handled in the same way for all patients. Category A;

Grade II

b. Linen from persons with a diagnosis of rare viral,

hemorrhagic fevers (e.g., Lassa, Ebola, Marburg)

requires special handling. For detailed handling

instructions refer to Health Canada's Canadian

Contingency Plan for Viral Haemorrhagic Fevers

and Other Related Diseases and, from the Centers

for Disease Control and Prevention, Management of

Patients with Suspected Viral Hemorrhagic

Fevers

(203,204)

. Category B; Grade III

c. Linen should be handled with a minimum of

agitation and shaking

(172,193,205)

. Category B;

Grade III

d. Sorting and rinsing of linen should not occur in

patient care areas, except in facilities that use colour-coded,

compartmented soiled linen bag carts into

which different types of linen are sorted, e.g.,

34.personal clothing, towels, reusable incontinence

products, bedding. Category B; Grade III

e. In community or home settings where clothes and

linens are not often soiled with blood or body fluids,

sorting of linen may take place in care areas

(193)

Category B; Grade III

f. Heavily soiled linen should be rolled or folded to

contain the heaviest soil in the center of the

bundle (172,193) . Large amounts of solid soil, feces or

blood clots should be removed from linen with a

gloved hand and toilet tissue and placed into a bed

pan or toilet for flushing. Excrement should not be

removed by spraying with water (e.g., from clothing,

reusable incontinence pads). Category B; Grade III

2. Bagging and containment

a. Soiled linen should be bagged at the site of

collection

(172,193,206)

. Category C; Grade III

b. To prevent contamination or soaking through, a

single, leakproof bag

(172,195,206)

or a single cloth bag

can be used

(205)

. The only indication for a second

outer bag is to contain a leaking inner

bag

(172,193,195,202)

. Category B; Grade II

c. Use of water soluble bags is not recommended as

these require hot water washes that may cause stains

to set. Water soluble bags offer no benefit from an

infection control per spective and needlessly add to

costs (172,193) . Category B; Grade III

d. Laundry carts or hampers used to collect or transport

soiled linen need not be covered

(193)

. The practice of

placing lids on soiled linen carts is not necessary

from an infection control perspective

(193)

. Category

B; Grade III

e. Bags should be tied securely and not over-fllled

when transported either by chute or cart

(172)

Category B; Grade III

f. Linen bags should be washed after each use and can

be washed in the same cycle as the linen contained in

them

(193)

. Category B; Grade III

3. Transport

a. When a laundry chute is used, all soiled linen must

be securely bagged and tightly closed. There have

been reports of bacteria-laden air being exhausted

upwards through these chutes; however, infections

have not been associated with chutes (172,193) . The

chute should discharge into the soiled linen

collection area. Laundry chutes should be cleaned on

a regular basis with a diluted germicide compatible

with the washing process

(206)

. Category B; Grade III

b. When linens are commercially laundered, adequate

separation of clean and dirty laundry in the truck is

essential to ensure that there is no opportunity for

mixing clean and dirty linens. Category B; Grade III

c. Linen transported by cart should be moved in such a

way that the risk of cross contamina tion is

minimized. There is no need to cover carts, although

odour control may be a fac tor

(115,193)

. Category B;

Grade III

d. Separate carts should be used for dirty and clean

linens. Carts used to transport soiled linens should be

cleaned with the cleaning product used in the health

care setting after each use. Category B; Grade III

e. Clean linen should be transported and stored in a

manner that prevents its contamination and ensures

its cleanliness

(115,193,207)

. Category B; Grade III

4. Washing and drying

a. If low temperature water is used for laundry cycles,

chemicals suitable for low temperature washing at

the appropriate concentration should be used.

Category B; Grade III

b. High temperature washes (> 71.1º C) are necessary if

cold water detergents are not used (193) . Category B;

Grade III

c. To achieve a level of at least 100 ppm of residual

chlorine with household bleach, 2 mL of household

bleach should be added for every litre of water. See

Table 7 for Directions for Preparing and Using

Chlorine-based Disinfectants. Category B; Grade III

d. In institutional laundry areas, addition of a mild

acidic "souring" agent neutralizes the alkalin ity from

the fabric, water and detergent. This shift in pH from

approximately 12 to 5 may inactivate any remaining

bacteria and reduce the potential for skin

irritation

(193)

. Category B; Grade III

e. Use of a commercial laundry detergent with

household bleach (according to product instructions

and where suitable for fabrics) and a normal machine

wash and machine dry are sufficient to clean soiled

linen in a community living or home care

setting (40,196-201) . Category B; Grade III

35.f. Machine drying or hanging clothing and linens on a

clothes line at the home care site is a suitable method

for drying. Category B; Grade III

5. Dry cleaning

Clothing containing blood, body fluids or excrement

that is sent to community dry cleaners should be

appropriately labelled. Dry cleaning personnel should be

knowledgeable of procedures to handle soiled clothing

items.

6. Sterile linen

Only surgical gowns and linens used in sterile

procedures should be sterilized

(193,207)

. Such linens should

be steam sterilized following the normal washing and

drying cycle to kill any residual spores. Resterilization of

previously sterilized linen requires laundering to

rehydrate it. Disposable items for use in sterile

procedures may be more cost-effective in some

situations. The need for sterilizing linens for nurseries

and other areas has not been substantiated

(193)

7. Protection of laundry workers

a. Workers should protect themselves from potential

cross infection from soiled linen by wearing

appropriate protective equipment, such as gloves

and gowns or aprons, when handling soiled

linens

(193,205-207)

. Reusable gloves should be washed

after use, allowed to hang dry, and discarded if

punctured or torn. Category B; Grade III

b. Hand washing facilities should be readily available.

Category B, Grade II

c. Personnel should wash their hands whenever gloves

are changed or removed

(84)

.Category B; Grade II

d. Staff in care areas need to be aware of sharps when

placing soiled linen in bags. Workers are at risk from

contaminated sharps, instruments or broken glass that

may be contained with linen in the laundry

bags

(172,193)

e. All care givers and laundry workers should be trained

in procedures for handling of soiled linen

(193)

Category B; Grade III

f. Laundry workers, as other health care workers,

should be offered immunization against hepatitis B.

36.Waste Management*

The management of waste generated in health care

settings has been the subject of much debate in recent

years because

• there is a public perception of a higher infection risk

from medical as compared with household waste,

despite evidence to the contrary;

• environmental concerns have limited the use of

incinerator or landfill as a final waste disposal site;

• health care fiscal restraint means that waste

management procedures must be based on evidence of

risk to workers or the public as well as of decreased

risk as a result of the procedures.

The waste management guidelines recommended in

this document will be based on the principles of disease

transmission and esthetic concerns (114,208-209) . The

management of waste described in this section will

reflect the current understanding of disease transmission

and risk, and incorporate an adaptation of the biomedical

waste guidelines prepared by the Canadian Standards

Association

(210-211)

. Because waste disposal now occurs

in many diverse health care settings these guidelines will

serve as a reference for both institutional and community

health care providers.

The categories of human biomedical waste generated

in health care are anatomic, microbiologic/laboratory,

blood/body fluid, sharps and isolation waste.

Biomedical waste is not necessarily infectious. Waste

documented to be associated with risk of disease

transmission are sharps contaminated with blood; as

well, aerosolization of the tubercle bacillus from medical

waste has been reported (212) . The ability of other waste

to cause disease depends upon the virulence of the

microorganism, susceptibility of the host, and a portal

of entry. Because there are no objective methods to

determine infection risk from waste, it has become

commonplace to regulate waste when it is suspected of

containing pathogens capable of producing disease. This

practice is not supported by evidence of risk from waste

or of decreased disease transmission associated with

these practices

(114,208,209)

A. Public Health Risk

Waste generated in health care settings is no more

hazardous than household waste. Data demonstrate that

household waste contains 100 times more pathogenic

organisms than medical waste

(213)

There is no evidence that any member of the public

has acquired disease from infectious waste

(114,208-209, 214)

All reports (except one

(212)

) of disease transmission from

biomedical waste have been a result of occupational

exposure to contaminated sharps in the health care

setting. Laboratory workers have unique exposure risks

and have incurred exposures that have resulted in

transmission of bloodborne pathogens (84) . As out-of-hospital

care increases, so will the number of sharps

disposed of by health care workers in the community

(148,215)

(refer to Table 10). At present, needles may be disposed

of in the household waste stream by recreational drug

users or persons requiring home health care

(59)

Accidental needlestick injuries have been reported in

10% of waste industry workers over one year because of

improper disposal of needles in residential waste

(217)

. In

*See Appendix 1 for definitions of the following terms: biomedical waste, infectious waste..Table 10. Recommendations for Management of Untreated Infectious Waste

Waste category* Examples Colour coding packaging† Handling disposal‡ Special considerations

Anatomic waste Tissues

Organs

Body parts

Sealed impervious

containers

Incineration, crematorium For religious or ethical reasons

anatomic waste may be buried in a

cemetery.

Microbiologic waste Diagnostic specimens

Laboratory cultures

Vaccines

Incineration

Autoclavable bags and plastic

waste holding bags for general

waste

Incineration or decontamination

by autoclave for landfill (211)

Blood/body fluid waste Phlebotomy bottles

Drainage collection units

Suction containers with blood

Placentas from home deliveries

Sealed impervious containers Sanitary sewer if permitted by

local regulatory authorities or

incineration

Other waste Gloves

Sponges

Dressings

Surgical drapes soiled or soaked

with blood or secretions

Impervious waste holding bags or

double bag

Landfill It is inappropriate to specify a

minimum thickness of plastic bag

as plastic materials vary

extensively in their physical and

mechanical properties.

Sharps Needles

Blood syringes

Lancets

Clinical glass

Puncture resistant sharps

containers

Incineration or landfill disposal

(home health care)

For health care provided in the

home use a puncture-resistant

container. Glass containers should

not be used. The lid should be

secured before disposal into

household waste. The local

municipality or public health

department should be contacted

before disposal (59,148,210,215)

Isolation waste Lassa fever

Marburg virus disease

Ebola virus disease

Transport Canada approved,

sealed, impervious container

Incineration Contact the local public health

authority (216) .

* As per definitions

† Biohazard symbol is required on all packaging for incineration; colour coding varies provincially and regionally.

‡ All transportation of infectious waste must comply with the Transportation of Dangerous Goods Act, Transport Canada (216) ..Canada, tracking methods for community-acquired

needlestick injuries, both in health care workers and non

health workers such as waste industry workers, require

further development

(218)

Esthetics plays a role in the management of

biomedical waste. The waste generated during health

care delivery is perceived by the public to pose a threat

to health. However, the public perception of hazard does

not equate with the actual risk of contracting infectious

diseases (213,219,220) .

Blood-soaked waste has also received much attention.

Increased public concern over bloodborne pathogens has

resulted in the erroneous extension of bloodborne

pathogen precautions to treat all blood/body fluid waste

as potentially infectious. Items soaked or dripping with

blood, contained in an impervious plastic bag before

being sent to the landfill, pose no threat to the public

health. Special treatment (e.g., incineration) of blood

soaked waste is not required, and has enormous cost and

environmental implications

(59,211,221,222)

Sharps contaminated with body fluid

(84)

and untreated

microbiologic waste

(188)

require special handling and

treatment. Sharps must be contained in a puncture-proof

container. Sharps and microbiologic waste should be

incinerated prior to disposal. Local environmental and

health regulatory authorities should be consulted when

implementing the waste treatment and disposal

recommended in this document.

B. Treatment of Waste

The treatment of infectious waste to render it non-infectious,

in some instances, may be stipulated by local

regulatory authorities. The principles of appropriate

treatment methods follow.

i) Chemical decontamination

Chemical decontamination of infectious fluids is

generally not indicated except for the cleanup of blood

spills

(84)

. Chemical treatment of sharps, such as adding a

disinfectant to a sharps container, does not render sharps

safe for further handling.

ii) Steam sterilization

Steam sterilization is most often used for

decontamination of microbiologic waste before final

disposal in a landfill (188) . Steam autoclaving is an

appropriate method of treating microbiology laboratory

waste

(189)

, blood and body fluid waste (if applicable), and

non-anatomic animal wastes. It must not be used for

treating anatomic waste

(210)

. The penetration of steam

into the waste is essential for decontamination, and

therefore the packaging of waste, and the volume and

loading of the autoclave are crucial. Biologic monitoring

should be used to confirm that a routine cycle achieves

sterilization

(210)

C. Disposal Methods for Waste

There are three common methods of waste disposal

for biologic waste in Canada, which may vary in

availability according to location.

i) Landfill

It is acceptable to dispose of specific categories of

waste in a properly managed landfill provided there are

procedures in place to protect workers from contact with

the waste. Studies have shown that bacteria and viruses

in a landfill are significantly reduced in number by

processes such as thermal inactivation and adsorption of

organic material in the solid waste. The leachate

similarly contains relatively low concentrations of

pathogenic organisms and therefore poses minimal risk

to the surrounding environment

(214)

. It is, however, an

overall environmental goal to reduce waste of all types,

including waste for disposal into the landfill. The landfill

disposal method is inexpensive when compared with

incineration

(220)

. Local regulations must be followed.

ii) Sanitary sewer

The sanitary sewer is an acceptable method of

disposal of blood, suctioned fluids, excretions and

secretions

(210)

. The disposal of such liquids into sanitary

sewers must conform to municipal sewerage by-laws and

provincial regulations and legislation

(211)

iii) Incineration

Incineration is the process that converts combustible

materials into noncombustible ash, achieving a reduction

of 90% by volume or 75% by weight. The product gases

are vented into the atmosphere, and the treatment residue

may be disposed of in a landfill. Provincial and territorial

regulatory authorities issue requirements for many

aspects of incinerator operation and emissions

(210)

D. Safety for Waste Handlers

Persons handling infectious waste are at potential risk

of exposure to pathogens from sharps or infectious waste

leaking from containers.

39.Recommendations for Waste Management

1. Local environmental and health regulations should be

followed when planning and implementing treatment

and disposal policies for biologic waste. Category B;

Grade III

2. Specific categories of biologic waste may be

disposed of in a properly managed landfill provided

that there are procedures in place to protect workers

and the public from contact with the waste. Category

B; Grade III

3. Medical waste, (e.g., gloves, sponges, dressings,

surgical drapes soiled or soaked with blood or

secretions) may be contained in impervious waste

holding bags or double bags and may be disposed of

in a landfill

(114,208,209)

. Category B; Grade III

4. Blood, suctioned fluids, excretions and secretions

may be disposed of in a sanitary sewer if local

regulations permit. Category B; Grade III

5. Anatomic waste, (e.g., tissues, organs, body parts)

should be packaged in a sealed, impervious container

that is not easily torn or penetrated in transport, and

may be disposed of in an incinerator or crematorium

(Table 10). Category B; Grade III

6. Microbiologic waste, (e.g., diagnostic specimens,

laboratory cultures, vaccines) should be packaged in

incineration or autoclavable bags and treated by

incineration or steam sterilization before disposal in a

landfill. Adhere to Laboratory Biosafety

Guidelines (188,210) . Category B; Grade III

7. Sharps (e.g., needles, syringes, blades, lancets,

clinical glass) should be contained in puncture-resistant

sharps containers for transport and treated

by incineration or landfill (home health care),

depending on local regulations (Table 10)

(211,218)

Category A; Grade II

8. Isolation waste (waste containing pathogens

categorized as Risk Group 4 agents such as Lassa

fever, Marburg and Ebola viruses) must be contained

in a Transport Canada approved, sealed, impervious

container for transport and should be treated by

incineration. Under the Transportation of Dangerous

Goods Regulations, Schedule 16, mandated by

Transport Canada (TC), any shipment of a Risk

Group 4 agent must have a TC approved Emergency

Response Assistance Plan in place before

shipment

(216)

. The local public health authority must

be contacted (203) . Category B; Grade III

9. A biohazard symbol is required on all waste

packaged for incineration. Regulations regarding

colour coding may vary provincially. Category B;

Grade III

10. All transportation of infectious waste must comply

with the Transportation of Dangerous Goods Act and

Regulation, Transport Canada

(216)

11. Infectious waste must be stored in a designated

location with access limited to authorized personnel.

Refrigerated space should be provided for lockable,

closed storage of laboratory waste that will be

disposed of off site

(188)

. Provincial/territorial

regulations for specific storage requirements should

be followed. Category B; Grade III

12. Health care facilities should choose waste hauling,

treatment, and disposal firms carefully since the

waste generator is held directly accountable for

ensuring that all stages of transportation and disposal

are carried out in a safe and legal manner

(188)

Category B; Grade III

13. Written policies and procedures to promote the safety

of waste handlers should be established with input

from persons handling the waste. Category B;

Grade III

14. Waste handlers should wear protective apparatus

appropriate to the risk, (e.g., protective footwear and

heavy work gloves). Category B; Grade III

15. Waste handlers should be offered hepatitis B

immunization.

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51.Appendix 1

Glossary

Antimicrobial agent: a product that kills or suppresses

the growth of microorganisms.

Antiseptics: chemicals that kill microorganisms on

living skin or mucous membranes. Antiseptics should not

be used in housekeeping.

Biofilm: the process of irreversible adhesion initiated by

the binding of bacteria to the surface by means of

exopolysaccharide material (glycocalyx). The develop-ment

of adherent microcolonies leads eventually to the

production of a continuous biofilm on the colonized

surface. Bacteria within biofilms tend to be more

resistant to antibiotics and biocides than cells in batch-type

culture.

Biomedical waste: defined by the CSA (210) as waste that

is generated by human or animal health care facilities,

medical or veterinary settings, health care teaching

establishments, laboratories, and facilities involved in the

production of vaccines.

Cleaning: the physical removal of foreign material, e.g.,

dust, soil, organic material such as blood, secretions,

excretions and microorganisms. Cleaning physically

removes rather than kills microorganisms. It is

accomplished with water, detergents and mechanical

action. The terms "decontamination" and "sanitation"

may be used for this process in certain settings, e.g.,

central service or dietetics. Cleaning reduces or

eliminates the reservoirs of potential pathogenic

organisms. Cleaning agents are the most common

chemicals used in housekeeping activity.

Critical items: instruments and devices that enter sterile

tissues, including the vascular system. Critical items

present a high risk of infection if the item is

contaminated with any microorganisms, including

bacterial spores. Reprocessing critical items involves

meticulous cleaning followed by sterilization.

Decontamination: the removal of disease-producing

microorganisms to leave an item safe for further

handling.

Disinfection: the inactivation of disease-producing

microorganisms. Disinfection does not destroy bacterial

spores. Disinfectants are used on inanimate objects;

antiseptics are used on living tissue. Disinfection usually

involves chemicals, heat or ultraviolet light. Levels of

chemical disinfection vary with the type of product used.

Fomites: those objects in the inanimate environment that

may become contaminated with microorganisms and

serve as a vehicle of transmission

(115)

Germicide: an agent that destroys microorganisms,

especially pathogenic organisms.

Hand wash(ing): a process for the removal of soil and

transient microorganisms from the hands.

Hand antisepsis: a process for the removal or

destruction of resident and transient microorganisms on

hands.

Heavy microbial soiling: the presence of infection or

high levels of contamination with organic material, e.g.,

infected wounds, feces.

High level disinfection: level of disinfection required

when processing semicritical items. High level

disinfection processes destroy vegetative bacteria,

mycobacteria, fungi and enveloped (lipid) and non

enveloped (non lipid) viruses, but not necessarily

bacterial spores. High level disinfectant chemicals (also

called chemisterilants) must be capable of sterilization

when contact time is extended. Items must be thoroughly

cleaned prior to high level disinfection.

Infectious waste: that portion of biomedical waste that

is capable of producing infectious disease

(219)

Intermediate level disinfection: level of disinfection

required for some semicritical items. Intermediate level

disinfectants kill vegetative bacteria, most viruses and

most fungi but not resistant bacterial spores.

52.Low level disinfection: level of disinfection required

when processing noncritical items or some

environmental surfaces. Low level disinfectants kill most

vegetative bacteria and some fungi as well as enveloped

(lipid) viruses (e.g., hepatitis B, C, Hantavirus, and HIV).

Low level disinfectants do not kill mycobacteria or

bacterial spores. Low level disinfectants-detergents are

used to clean environmental surfaces.

Noncritical items: those that either touch only intact

skin but not mucous membranes or do not directly touch

the patient. Reprocessing of noncritical items involves

cleaning and/or low level disinfection.

Plain or nonantimicrobial soap: detergent-based

cleansers in any form (bar, liquid, leaflet, or powder)

used for the primary purpose of physical removal of soil

and contaminating microorganisms. Such soaps work

principally by mechanical action and have weak or no

bactericidal activity. Although some soaps contain low

concentrations of antimicrobial ingredients, these are

used as preservatives and have minimal effect on

colonizing flora.

Sanitation: a process that reduces microorganisms on an

inanimate object to a safe level (e.g., dishes and eating

utensils are sanitized).

Semicritical items: devices that come in contact with

nonintact skin or mucous membranes but ordinarily do

not penetrate them. Reprocessing semicritical items

involves meticulous cleaning followed preferably by

high-level disinfection (level of disinfection required is

dependent on the item, see Table 5). Depending on the

type of item and its intended use, intermediate level

disinfection may be acceptable (see Table 5 for

examples).

Sharps: needles, syringes, blades, laboratory glass or

other objects capable of causing punctures or cuts.

Sterilization: the destruction of all forms of microbial

life including bacteria, viruses, spores and fungi. Items

must be cleaned thoroughly before effective sterilization

can take place.

53.Appendix 2

Guideline Rating System

The Laboratory Centre for Disease Control (LCDC)

Infection Control Guidelines previously used a system

for rating guideline statements based on the strength of

the evidence

(15,71)

. A more elaborate system of rating has

recently been proposed

(223)

, with five categories to rank

the strength of the evidence for (categories A-C) or

against (D-E) a statement, and three grades to describe

the quality of supportive studies. This system of rating

follows the guidelines that have been recently published

for clinical practice guidelines. The format uses an

evidence-based medicine approach, which stresses the

examination of evidence from clinical research,

especially randomized studies, and places less emphasis

on intuition and recalled experiences.

This new rating scheme, with one modification, is

used in this document with appropriate clarification of

evidence described in the text. The modification occurs

in Category C with the word "insufficient" replacing

"poor" in the original rating scheme. This system is

outlined in Table 11.

The information in these guidelines was current at the

time of publication; it should be emphasized that areas of

knowledge and aspects of medical technology advance

with time. Guidelines, by definition, are directing

principles and indications or outlines of policy or

conduct, which should not be regarded as rigid standards.

These guidelines should facilitate development of

standards but respect the autonomy of organizations and

recognize their governing body's authority and

responsibility to ensure the quality of care provided by

the institution.

Table 11: Strength and Quality of Evidence for Recommendations

Categories for strength of each recommendation

Category Definition

A Good evidence to support a recommendation for use.

B Moderate evidence to support a recommendation for use.

C Insufficient evidence to support a recommendation for or against use.

D Moderate evidence to support a recommendation against use.

E Good evidence to support a recommendation against use.

Categories for quality of evidence on which recommendations are made

Grade Definition

I Evidence from at least one properly randomized, controlled trial.

II Evidence from at least one well-designed clinical trial without randomization, from cohort or case- controlled

analytic studies, preferably from more than one centre, from multiple time series, or from dramatic results in

uncontrolled experiments.

III Evidence from opinions of respected authorities on the basis of clinical experience, descriptive st udies, or

reports of expert committees..Appendix 3

Drugs Directorate Guidelines

For more information regarding disinfectants and for

an order form for publications of the Drugs Directorate,

including the Drugs Directorate Guidelines, visit the

website at the following address:

www.hc-sc.gc.ca/hpb-dgps/therapeut

For further information from the Therapeutics

Products Programme, Bureau of Pharmaceutical

Assessment, Health Protection Branch, Health Canada,

telephone (613) 965-6466 and (613) 954-6503.

Erasing Skin Marks with Lasers
by Ricki Lewis, Ph.D.

Port-wine stains can make life difficult for people of all ages. Donna
Arnds, a 23-year-old from north Los Angeles, has marks on her nose, eyelids
and lips. In high school, she never attended a dance because, she says, no
one wanted to be seen with her. Anne Plescia, 40, of Ithaca, N.Y., was often
mistaken to be mentally retarded because of her facial birthmarks. "I've
been in conversations where they will only address my husband, assuming I
have no intellect," she says.

Thousands of parents have agonized as their birthmarked children approach
school age "when the kids are old enough to be cruel," notes Linda Margalith
of Beverly Hills, Calif., mother of 3-year-old Alexa.

For Gina Brass of Escondito, Calif., the suffering was even worse. Many
people who saw the marks on her 6-year-old daughter's cheek and chin would
accuse her of physically abusing the child, causing her "bruises." These and
many other people with birthmarks have been helped by a new type of
treatment using laser devices, which are regulated by the Food and Drug
Administration. The treatments for benign (noncancerous) skin lesions
possible with lasers extend beyond birthmarks, to include liver spots,
spider veins, residual redness following plastic surgery on the nose, and
even tattoo> removal.

The temporary redness, swelling, and a bruised appearance that can occur
after laser treatment of the skin are preferred by some patients to the
discomforts of older methods, which include freezing tissue with liquid
nitrogen, electrosurgery, scraping off (curettage) the affected area,
treating the area with chemicals such as Retin A (tretinoin) or acids, or
masking marks with make-up. When used by physicians who are trained in the
use of a laser, results can be quite dramatic. But in less well-trained
hands, a laser can cause damage and scarring, just as traditional surgery or
scraping can.

Lasers used in these treatments include: carbon dioxide, argon, continuous
tunable dye, ruby, copper vapor, and flashlamp-pumped pulsed dye (see
accompanying article). Here is a rundown on what these new lasers can do
when applied to the skin.

Port-Wine Stains

A beet-colored mark splashed across a small face can be the butt of many
children's jokes.

"Reaction depends on the individual child, but especially when one hits
school age, the teasing is unbelievable," says Tina Dawn, president of the
National Congenital Port-Wine Stain Foundation in New York City. "I've known
children to throw their eyes out of whack because they constantly keep their
heads down to hide the stain," she adds. For these children, successful
treatment can literally turn their lives around.

Because the idea of a laser can be frightening, the staff at the University
of Massachusetts Medical Center in Boston gives each patient a Raggedy Ann
or Raggedy Andy doll that has a matching mark made in red crayon. The doll
receives a laser treatment to show the child how the mark disappears, and to
quiet fears.

To remove a port-wine stain, a small area on the patient's arm is first
tested, and then the mark is treated. Anesthesia is not used unless the area
to be treated is extensive, and then local anesthesia is used.

The laser feels like a small rubber band being snapped against the skin. For
the first 24 hours, the area swells and reddens, the signs of the body's
immune response to the vaporized blood vessels in the birthmark. The area
turns a bluish-gray with purplish-red spots for 7 to 10 days. The spots
fade, and the treated area continues to lighten over the next eight weeks.

But it may be difficult to locate a physician who is experienced with this
relatively new procedure. "The average dermatologist has yet to have a laser
available, but more and more are getting them, says Dawn. "Now, only
specialized medical centers and some dermatologists have them."

Using the flashlamp-pumped pulsed dye laser to treat port-wine stains
requires more sessions to fade the mark than with other lasers, and bumpy
lesions do not respond well.

Still, this type of laser is currently the one recommended to treat
children--and the sooner the lesion is treated, the better the results. Blas
Reyes, M.D., and Roy Geronemus, M.D., of the New York University Medical
Center, treated port-wine stains in 73 patients between the ages of 3 months
and 14 years, and discovered three reasons to zap a port-wine stain as soon
as possible:
- the skin thickens up to age 20, when it becomes more difficult to treat
- the extraneous blood vessels are smaller in diameter in a youngster
- the stain itself occupies a smaller area in the young.

Spots, Freckles, Moles, and Spiders

A cousin to the "vascular lesion laser" used to treat port-wine stains is a
pigmented lesion laser, which FDA cleared for use in May 1991. It is used to
treat lentigines (also known as age, sun or liver spots), moles, freckles,
and brown birthmarks, which millions of people have. This laser zeroes in on
melanin, the pigment found in the epidermis, the outer skin layer.

The pulse delivered by the pigmented lesion laser lasts one-third of a
millionth of a second, and covers an area the size of a pea. It, too, feels
like a rubber band snap. Two weeks after treatment, the skin peels away and
is replaced from beneath with a new, unblemished epidermis.

"Many people develop solar lentigines early in adult life, particularly
people from the Southwest. Not only are these lesions unsightly, but they
are associated with old age. Removing the lesions seems to enhance people's
self-confidence significantly," says Joseph Morelli, M.D., assistant
professor of dermatology and pediatrics at the University of Colorado School
of Medicine in Denver.

Too much sun is linked to a number of types of skin lesions. "Exposure to
the sun thins the skin, making it more transparent. It also causes
enlargement of the blood vessels on the skin's surface, which in turn makes
these vessels more visible. Plastic surgeons refer to these red, unsightly
vessels as telangiectasias, or 'spiders'," says Joel M. Noe, M.D., assistant
professor of plastic and reconstructive surgery at Harvard Medical School.

Often, spiders are caused by chronic overexposure to the sun, but they may
also result from liver disease or occur in pregnancy due to a change in the
way the body processes estrogen. In addition, they can be a side effect of
oral contraceptives or prolonged use of topical corticosteroid drugs. They
may also occur with a little-understood condition called rosacea, in which
the middle third of the face is affected.

"These conditions responsible for red blood vessels on the face are
incredibly common in our society, especially among the fair-skinned who have
had lots of sun exposure," Noe adds.

He uses argon or pulsed dye lasers to treat spiders. "It can be done in the
doctor's office using local anesthesia. The treatment produces a mild
sensation of heat and a feeling like pinpoints lightly touching the skin,"
he says. Usually one or two treatments are needed.

Ultraviolet exposure from excessive sunning can wreak havoc on recovery from
plastic surgery on the nose, producing redness called "post-rhinoplasty red
nose" as new blood vessels appear on the bridge of the nose. This is part of
the healing process and is preventable by minimizing sun exposure. It can be
covered with make-up, or treated with an argon laser, says Noe.

Bleaching Cream Backfires

A 53-year-old black woman had used an over-the-counter "skin whitener cream"
to even out her complexion for three months when she noticed just the
opposite effect--a sooty, bluish-black raised area on her face. Her doctors
first tried to lighten the area by treatments with the acne drug Retin-A,
cryosurgery with liquid nitrogen, and finally by peeling off the skin
pigment with trichloroacetic acid. These dermabrasion procedures worked on
parts of her face, but not on the thin-skinned areas near her eyes and nose.
She consulted Edgar Smith, M.D., and his colleagues at the University of
Texas Medical Branch in Galveston, who had reported success with a carbon
dioxide laser.

Sooty marks resulting from lightening creams are due to the ingredient
hydroquinone, which can cause pigmented fibers to be gradually laid down in
the dermis (the underlying skin layer). In the mid 1970s, doctors in South
Africa began reporting the mysterious dark spots on the faces of black
people who had used products containing 6 to 8 percent hydroquinone, and, as
a result, the amount was limited in many countries, including the United
States, to 2 percent. Still, in the 1980s, cases were reported among U.S.
blacks.

So far only blacks have been reported to be affected, and their skin
responses range from redness and mild pigmentation, to dark coloration, to
the appearance of nodules. Although the CO2 laser is now the only one used
on these blemishes, Smith suggests that a ruby laser may work even better,
considering the recently reported success of this type of laser in removing
<tattoos>.

<Tattoos> Skidoo

Since 6000 B.C., people have had their skin <tattooed>--and then later
regretted it. Unfortunately, treatments to remove the marks often marred the
skin further. Ronald Wheeland and co-workers of the University of California
at Davis reported in the December 1990 Journal of Dermatological and
Surgical Oncology that a preliminary study indicated treatment with a ruby
laser to remove <tattoos> is "vastly superior" to standard methods, such as
dermabrasion and surgical removal.

The ruby laser works much the way the pigmented lesion laser does, and also
feels like a rubber band snap. The laser light is absorbed by melanin and
the carbon-based pigments used in <tattoos>. The skin initially turns white
for 10 to 20 minutes, then swells and turns red, feeling like a sunburn.
Although the skin stays red for one to three weeks, healing takes 10 to 14
days, and fading continues for months. There are no open wounds. The
researchers treated 163 <tattoos> on 80 patients and found that black and blue
<tattoos more than 10 years old responded best to the treatment.

The success of laser surgery in treating benign skin lesions has encouraged
many people to seek help who would otherwise have relied on disguising or
hiding their blemishes. Lasers have also helped thousands of others who were
unhappy with the results of more traditional treatments. In the future, this
kind of laser surgery may become more common for an increasing number of
people with problems that are more than skin deep. n

Ricki Lewis, a writer in Scotia, N.Y., teaches biology at the State
University of New York at Albany.
Laser Basics

Since the mid-1960s, lasers have proven to be powerful surgical tools. The
word "laser" is actually an acronym for "light amplification by stimulated
emission of radiation," which means that the intense and narrow beam of
light is of one wavelength. Ordinary "white" sunlight, in contrast, is a
continuum of light of many wavelengths, corresponding to the colors of the
spectrum plus the infrared (heat) and ultraviolet wavelengths that sandwich
them.

A medical laser device includes a source of electricity, mirrors to direct
the beam, a crystal or gas that is stimulated to emit the light, and tubing
to deliver the energy. Design of the instrument is tailored to specific uses.

"The diameter of the light beam is picked to match the diameter of the area
to be treated," says Joel M. Noe, M.D., assistant professor of plastic and
reconstructive surgery at Harvard Medical School. "For example," he
explains, "to treat a blood vessel 1 millimeter in diameter, you would use a
1-millimeter handpiece. If the target is a group of vessels, you would use a
larger diameter handpiece."

About 5 percent of the nation's 10,000 plastic surgeons use lasers, says Noe.

FDA regulates lasers, including those for medical uses. "FDA evaluation is
of the device itself. We try to find out if the device to be marketed is
equivalent to another device on the market. It does not have to be superior.
We look at safety and efficacy," says Sankar Basu, Ph.D., a physicist with
FDA's surgical devices evaluation branch.

The radiation a laser emits depends on the chemical through which it passes.
A carbon dioxide (CO2) laser, for example, emits energy that can heat water;
it can vaporize watery tissue near the body's surface. In dermatology, CO2
lasers are used to remove warts, lip lesions, and ingrown toenails. CO2
lasers, however, have no effect on blood, which permeates tissue beneath the
skin's outer layer.

The blue-green emission of an argon laser is suited for tissue with a lush
blood supply. It passes right through watery tissue, but is absorbed by
hemoglobin, the vibrant red protein in red blood cells that carries oxygen
to the body's tissues. In a port-wine stain, hemoglobin courses through the
abnormally numerous blood vessels in the underlying skin layer. An argon
laser can destroy these extra vessels, lightening the marks in 80 percent of
adult cases. But a child's delicate skin can be badly scarred by the
powerful argon laser.

A gentler laser for benign skin conditions is a flashlamp-pumped pulsed dye
laser, which FDA cleared for use in 1987. The device consists of a dye
(rhodamine in methanol) that is excited by high-intensity flashlamps to
release photons, which are tiny subatomic packets of light energy. Like an
argon laser, the wavelength of the pulsed dye laser is absorbed by
hemoglobin, but it is less powerful. When aimed at the skin, a few brief
pulses safely zap away the blood vessels. The trick is to apply the light
pulses faster than the blood vessels can dissipate the heat. A pulse of this
laser takes 360 to 450 microseconds, and the blood vessels need about 3
milliseconds (equal to 3000 microseconds) to recover. In contrast, an argon
laser pulse typically takes five-hundredths of a second, long enough to
damage much more than the stain, and thereby cause a scar to form.

The ability of the flashlamp-pumped pulsed dye laser to treat port-wine
stains was first reported in the Feb. 16, 1989, New England Journal of
Medicine by Oon Tian Tan, M.D., and colleagues of the Boston University
Medical Center. Since then, other studies have confirmed their findings--and
approximately 60,000 persons have had their birthmarks removed worldwide,
according to the Candela Laser Corp. in Wayland, Mass., which markets the
device and keeps track of its use.

--R.L.

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