cfpp 01 01 partd final

7/23/2019 Cfpp 01 01 Partd Final

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By-Email

For Action:Chief Executives HSC TrustsChief Executive HSC BoardChief Executive HSC Public Health AgencyChief Executive NI Blood Transfusion AgencyDecontamination Leads

For Information:Chief Executive RQIA

Health Estates Investment Group (HEIG)

Annexe 6, Castle Buildings, Belfast BT4 3SQNorthern Ireland

Tel:Fax: 028 9052 3900E-mail:Website: www.healthestatesni.gov.uk

Our Ref:PEL (13) 12

Date: September 2013

Dear Colleagues

CHOICE FRAMEWORK FOR LOCAL POLICIES AND PROCEDURES (CFPP) 01-01: MANAGEMENT AND DECONTAMINATION OF SURGICAL INSTRUMENTS(MEDICAL DEVICES) USED IN ACUTE CARE: PARTS A, B, C, D, E FOR USE INNORTHERN IRELAND

Background

Following closure of the Space for Health website (PEL (13 ) 05 refers) this letter is

to advise HSC organisations of the transfer of these guidance documents to theDepartment of Health , Social Services and Public Safety (Northern Ireland) website.

PEL (12) 12 dated 10 July 2012 which covered the issue of the above guidance isnow superseded by this letter.

This letter also outlines specific Northern Ireland policy amendments that apply tothe guidance.

CFPP 01-01 Part A: The formulation of local policy and choice manualCFPP 01-01 Part B: Common elementsCFPP 01-01 Part C: Steam sterilizationCFPP 01-01 Part D: Washer-disinfectorsCFPP 01-01 Part E: Alternatives to steam sterilization of reusable medical devices

Policy Context

Choice Framework for local Policy and Procedures (CFPP) is a suite of best practiceguidance that is currently being piloted by the Department of Health (DH) England topotentially replace guidance previously provided in the form of Health TechnicalMemorandum and Health Building Notes. The CFPP framework is designed to

reflect the need to improve efficiency and outcomes in terms of safety, clinicaleffectiveness and patient experience in line with health policy direction being taken


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by the UK government for the modernisation of the NHS in England as outlined inthe Health and Social Care Act 2012.

The Health and Social Care Act gives power to clinicians to make commissioningdecisions and therefore advocates the adoption of an Essential QualityRequirements leading to Best Practice approach to allow greater choice forcommissioners across providers (both NHS and private sector) using a risk-controlapproach to the management and decontamination processes for reusable surgical

instruments.

The Health and Social Care Act does not apply in Northern Ireland and the adoptionof an Essential Quality Requirements leading to Best Practice approach does notmeet current DHSSPS policy developed to meet the strategic delivery framework forthe decontamination of reusable surgical instruments used by Health and SocialCare bodies in Northern Ireland (DHSSPS Circular reference HSS(SC)3/04 Decontamination of Reusable Surgical Instruments). This policy states that:

Decontamination of reusable surgical inst ruments should be carried out in l inewith current best practice and standards, and where practicable, single use

surgical instruments utilised, to minimise the risk of cross infection topatients, staff and the public.

Northern Ireland Amendments

The following Northern Ireland policy amendments apply to the CFPP 01-01 suite ofdocuments:

1. Health and Social Care providers in Northern Ireland are required to meet bestpractice requirements as outlined in the suite of documents i.e. meetingessential quality requirements and having a plan to meet best practice asoutlined in the England version of the documents is not acceptable in NorthernIreland.

2. In CFPP 01-01 Part A, Element 13728, the guidance on Decontamination ofsurgical instruments that have been dropped preoperatively is at odds withDHSSPS decontamination policy and is not acceptable in Northern Ireland. Thiselement is replaced by the Dropped Instrument Risk Assessment andManagement (Wales NHS) model see Appendix 1.

3. Health Technical Memoranda 2010 and 2030 are to remain in use in Northern

Ireland for laboratory sterilizers and washer-disinfectors for human wastecontainers respectively, until appropriate CFPP 01-01 documents are developedfor this range of equipment.

4. Current arrangements for the DHSSPS Authorising Engineer (Decontamination)assurance function remain unchanged.

5. Northern Ireland readers should refer to the equivalent Northern Irelandlegislation and DHSSPS policy and guidance for references to GB Legislationand DH policy circulars.


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APPENDIX 1

Dropped Instrument Risk Assessment and Management (Wales NHS)

Yes

No

Yes

No

Yes

No

Yes

No

Yes

No

Instrument Dropped

Can operation proceed

without instrument?

Has surgery started or did the

incident occur during the setting out

period?

Surgery hasstarted

Surgery has

not started

Can procedure be

abandoned?

Is a

duplicate

instrument

set

available?

Non-scrub team member retrieves

the instrument from floor, simpledecontamination and quarantine

until end of procedure when

instrument should be reunited with

instrument set

Return complete

pack with dropped

instrument to

HSDU, use

replacement set and

proceed

Abandon procedure

and ensure post op

patient counselling

to discuss

implications

Open second set and

use replacement

instrument

Note details of the

two sets used for

this patient in case

of later follow-up

Arrange for rapid

decontamination in

HSDU and proceed

with surgery as

instrument becomes

available

Non scrub team member undertakes handwash, dons sterile

gloves, and undertakes simple, superficial decontamination

with sterile water and returns to scrub team

Report adverse event and patient details in accordance

with board protocol

Note incident in operative notes for the patient

Is a duplicate instrument

set available?

Can instrument be

rapidly

decontaminated by

HSDU without

detriment to patient?

Simple limited

decontamination

in theatre is only

option?


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Choice Framework for local Policy andProcedures 01-01 Management and

decontamination of surgical

instruments (medical devices) used in

acute care. Part D:Washer-disinfectors


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Choice Framework for local Policy andProcedures (CFPP) 01-01Management and decontamination ofsurgical instruments (medical devices) used inacute care

Part D: Washer-disinfectors


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iii

Preface

Introduction

The Choice Framework for local Policy and Procedures(CFPP) is an initiative being piloted by the Departmentof Health.

It forms a suite of evidence-based policy and guidance

documents on the management and decontamination ofreusable medical devices.

Purpose

The purpose of CFPP is to enable local choices to bemade regarding the management, use anddecontamination of reusable medical devices at controlledcosts using risk control.

CFPP is designed to reflect the need to continuouslyimprove outcomes in terms of:

patient safety;

clinical effectiveness; and

patient experience.

Essential Quality Requirements andBest Practice

The Health Act Code of Practice recommends thathealthcare organisations comply with guidanceestablishing Essential Quality Requirements anddemonstrate that a plan is in place for progression to BestPractice.

Essential Quality Requirements (EQR), for the purposesof this best practice guidance, is a term that encompassesall existing statutory and regulatory requirements. EQRsincorporate requirements of the current Medical Devices

Directive and Approved Codes of Practice as well asrelevant applicable Standards. They will help todemonstrate that an acute provider operates safely withrespect to its decontamination services.

Local policy should define how a provider achieves riskcontrol and what plan is in place to work towards BestPractice.

Best Practice is additional to EQR. Best Practice asdefined in this guidance covers non-mandatory policiesand procedures that aim to further minimise risks topatients; deliver better patient outcomes; promote andencourage innovation and choice; and achieve costefficiencies.

Best Practice should be considered when developing localpolicies and procedures based on the risk of surgicalprocedures and available evidence. Best Practice

encompasses guidance on the whole of thedecontamination cycle, including, for example, improvedinstrument management, where there is evidence thatthese procedures will contribute to improved clinicaloutcomes.

The CFPP suite is listed below.

Choice Framework for local Policy and Procedures01-01: Management and decontamination of surgicalinstruments (medical devices) used in acute care

Choice Framework for local Policy and Procedures

01-04: Decontamination of linen for health and socialcare

Choice Framework for local Policy and Procedures01-06: Decontamination of flexible endoscopes


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CFPP 01-01 Management and decontamination of surgical instruments: Part D Washer-disinfectors

vi

Choice Framework for local Policy and Procedures(CFPP) 01-01 offers best practice guidance on the wholedecontamination cycle including the management anddecontamination of surgical instruments used in acutecare.

Part A covers the policy, management approach andchoices available in the formulation of a locallydeveloped, risk-controlled operational environment. Thetechnical concepts are based on European (EN),International (ISO) and British (BS) Standards usedalongside policy and broad guidance. In addition to theprevention of transmission of conventional pathogens,precautionary policies in respect of human prion diseasesincluding variant Creutzfeldt-Jakob disease (vCJD) areclearly stated. Advice is also given on surgical instrumentmanagement related to surgical care efficiencies andcontingency against perioperative non-availability of

instruments.Part B covers common elements that apply to all methodsof surgical instrument reprocessing such as:

test equipment and materials

design and pre-purchase considerations

validation and verification.

Part C covers standards and guidance on steamsterilization.

Part D covers standards and guidance on washer-

disinfectors.

Part E covers low temperature (non-steam) sterilizationprocesses (such as the use of vapourised hydrogenperoxide gas plasmas and ethylene oxide exposure).

CFPP 01-01 Part A supersedes Health TechnicalMemorandum 01-01 Part A (2006).

CFPP 01-01 Parts BE supersede Health TechnicalMemoranda 2010, 2031 and Health Building Note 13Supplement 1, and partially supersede Health TechnicalMemorandum 2030. Only washer-disinfectors used for

processing surgical instruments (and not those used inlaboratories or for endoscopes) are covered in CFPP01-01.

Executive summary


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Contents

PrefaceIntroductionPurposeEssential Quality Requirements and Best Practice

AcknowledgementsAbbreviations

Executive summary1 Design and pre-purchase considerations 1

Purpose of washer-disinfectorsChoice of washer-disinfector

Categorisation of washer-disinfectors by nature of load to be processedCategorisation of washer-disinfectors by configuration/load handling typeWhen is a washer-disinfector required?Choice of washer-disinfectorAssessment of workload and throughputRigid endoscopesPowered devices

Specification and contractIntroductionCE markingPreparing a specificationConstruction materialsIntegral air compressorsIntegral calorifiers and tanksDosing systemsDoor controlsLoading systemsCleaning the washer-disinfectorSteam

Integral steam generatorsCondensate recoveryCompressed airDrainageHazardous effluentsMachine ventilationChemical additives: storage

Chemical additivesIntroductionCompatibility with the materials of construction of the washer-disinfectorCompatibility with the process

Compatibility with the items to be processedCompatibility with the quality of waterCompatibility with other chemical additivesCompatibility with subsequent decontamination processes


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3 Water supply 40IntroductionWater hardnessIonic contaminants

Microbial populationConcentration of bacterial endotoxinsWater treatment

Chemical purityMicrobial purity

PipeworkWater supply by-lawsWater system tests

Water samplesWater quality tests

Choice of method

Water supply temperatureApparatusMethodAlternative method (for periodic testing)Results

Water supply pressureApparatusMethodResults

AppearanceApparatusMethod

ResultspH

ApparatusMethodResults

Electrical conductivityEquipment and materialsMethodResults

Total dissolved solidsConductivity method

ResultsEvaporative residue method

ResultsHardness (as CaCO3)

Ion-selective electrodes (ISE) methodTitrimetric methodResults

ChlorideIon selective electrode (ISE) methodSilver nitrate titration methodResults

Heavy metalsMethodResults

Iron

Contents

ix


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Phosphate


SilicateApparatusMethodResults

Bacterial endotoxinsApparatusMethodAnalytical procedure

Sources of errorSafety informationResults

Total viable countApparatusMethod: sample collectionMethod: testingResults

4 Operational management 57Introduction

Equipment damageMaintenance

IntroductionPlanned maintenance programmePressure Systems Safety RegulationsFeatures requiring special attentionReturning a washer-disinfector to serviceTroubleshooting

Appendix A: Particular specification for washer-disinfectors used for processing surgical instruments 63References 64


x


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1

Purpose of washer-disinfectors

1.1 Washer-disinfectors are used to clean and disinfectitems intended for re-use. They may be used inrelation to both medical devices and medicinalproducts as well as other items

1.2 The cleaning and disinfection process is intendedto:

make the item safe for staff to handle;

make the item safe for use on a patient (afterany necessary additional processing such as aterminal sterilization process), including, ifappropriate, ensuring freedom fromcontamination that could lead to an erroneousdiagnosis.

1.3 When items being cleaned and disinfected by a

washer-disinfector are intended to be used againwithout further treatment (such as a terminal

sterilization process), before being reused thewasher-disinfector should produce an item that ismicrobiologically safe for its intended use.

1.4 When the items being cleaned/disinfected by awasher-disinfector are intended to be subjected tofurther processing (such as a terminal sterilizationprocess) before being re-used the disinfection stagein the washer-disinfector should produce an itemthat is microbiologically safe to be handled duringpreparation for subsequent processing.

1.5 Washer-disinfector processing involves two distinctstages: cleaning and microbial inactivation. Thelatter can be achieved by disinfection, sterilizationor both (disinfection followed by sterilization).Washer-disinfectors are used to decontaminateitems intended for re-use by subjecting the items toan automated process of cleaning and disinfection.This is shown in Figure 1.

1 Design and pre-purchase considerations

Clean

Wash+

Disinfect

and/or sterilize+

Flush

Decontaminate

Physicalremoval of

gross soilingwith copiousqualities of

water

Aqueous mediumtogether withdetergents,enzymaticcleaners,

ultrasonication,water jets etc as

appropriate

Thermal or chemicaldisinfection, as

appropriate, to yield aproduct that is safe forreuse or sfae to handle

for inspection,reassembly, packing

and sterilization beforeuse

Figure 1 Elements of the decontamination process


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1.6 The efficacy of the cleaning stage of the process isof crucial importance to the successful outcome ofthe disinfection stage.

Choice of washer-disinfector

Categorisation of washer-disinfectors by nature ofload to be processed

1.7 Washer-disinfectors may be categorised accordingto their intended use, i.e. the nature of the loadthey are intended to process:

1.8 Washer-disinfectors may be further defined both bytheir configuration/load handling system and bythe nature of the operational process.

1.9 Washer-disinfectors may be used for processing awide range of products used in clinical practice.Loads will include surgical instruments, anaestheticequipment, bowls, dishes, receivers, utensils andglassware. Further information, includingvalidation protocols can be found in BS EN ISO15883.

Categorisation of washer-disinfectors byconfiguration/load handling type

1.10 Washer-disinfectors may also be categorized by

their construction and the manner in which theload is processed through the machine.

Single-chamber machines

1.11 Single-chamber machines have one chamber inwhich the full range of process stages are carriedout. They are machines in which all stages of thecycle are completed on one chamber load beforeanother load can be processed in that chamber.

1.12 These might have either a single door throughwhich both loading and unloading takes place ordouble doors with one door being used for loadingand the other for unloading.

Multi-chamber machines

1.13 Multi-chamber machines have more than onechamber where separate stages of the cycle areperformed in each chamber. The full range ofprocess stages is only completed when the load isdelivered from the final chamber. The segregationof cycle stages may be determined by specific Userrequirements but, typically, the chambers will bededicated to cleaning, disinfection and drying.Different loads may be processed concurrently. Anextra chamber for ultrasonic cleaning may also be

included. These machines will have doors at eitherend and at intermediate positions betweenchambers.

Conveyor machines

1.14 Washer-disinfectors of this type may find it difficultto meet the requirements of some validation andperiodic tests and are thus not recommended.Current machines of this type should be replaced.

Thermal disinfection

1.15 In this process disinfection is achieved by the actionof moist heat maintained on the surface to bedisinfected at a particular temperature for aparticular time. The combination of time andtemperature should satisfy the A0 requirement ofBS EN ISO 15883-1 for disinfection to beachieved.

1.16 The A0concept is defined in BS EN ISO 15883-1.It is defined as the disinfection effect resulting froman exposure to 80C for a period of 1 s for anorganism with a z-value of 10C. Time/temperaturebands meeting the requirements of an acceptableA0of 600 are as follows:

Disinfection

temperature (C)

Maximum

allowabletemperature (C)

Exposure time

period

70 75 100 minutes

80 85 10 minutes

90 95 1 minute

Drying

1.17 Drying can be an integral part of the cycle, usuallyby the circulation of hot air over the product, orprovided as a separate drying cabinet. For someproducts, for example corrugated anaesthetictubing, prolonged drying times are recommendedand a separate drying cabinet can improve theproductivity of the washer-disinfector.

1.18 A dry product can also be obtained by the flashevaporation of residual moisture from productitems that are hot following a high temperaturethermal disinfection stage.

When is a washer-disinfector required?

1.19 For many products used in healthcare practice there

are two choices available: products intended for re-use after they have

been decontaminated and subjected to any


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necessary reprocessing (for example terminalsterilization);

single-use products, that is, to be discarded after

use.1.20 Products that are intended to be re-used should be

decontaminated, in accordance with themanufacturers instructions, in one of the followingways:

manual cleaning followed by disinfection andsterilization;

machine cleaning followed by disinfection andsterilization;

automated machine decontamination

incorporating cleaning.

1.21 See MHRAs Device Bulletin MDA DB 2006(04) Single use medical devices: implications andconsequence of reuse.

Note

HSC 1999(178) Variant Creutzfeldt-Jakob disease(vCJD): minimising the risk of transmission statesthat medical devices designated as single-use shouldnever be re-used.

Choice of washer-disinfector

1.22 The choice of washer-disinfector should bedetermined by the nature of the loads to be cleanedand disinfected.

1.23 Purchasers should be aware that items suitable for aparticular type of washer-disinfector might stillrequire different operating cycles, which need to bespecified before purchase.

1.24 Guidance on the modification of operating cycles

to suit different loads is given in Chapter 4,Operational management. Advice on individualcases should be sought, if necessary, from theAE(D) before any decision is made. Use should bemade of the Particular specification for washer-disinfectors given inAppendix A.

1.25 Once the type of washer-disinfector has beendecided, preliminary enquiries should be madewith a number of manufacturers The use of theParticular specification in Appendix A will enabledata provided by the tenderer on technical points as

well as financial data to be compared. Not only willthis enable the purchaser to confirm theacceptability of current services, spatialrequirements and porterage but it will enable a like-

for-like tender analysis to be made. Tender analysiswill be best achieved by formalizing tendercomparison with respect to performance and costin all key areas. Qualifying statements by the

tenderer should be taken into account and theireffect on tender content or eligibility should bemade prior to a choice being made. See AppendixA for the Particular specification for washer-disinfectors.

1.26 The dispensed volume of the chemical additives(e.g. detergents), including the accuracy andreproducibility of the dosing system(s), should bespecified.

1.27 For washer-disinfectors employing jet-washing

systems, the pump pressure and water flow are alsocritical variables. Water quality will also be a criticalvariable where water is used for cleaning ordisinfection. Where drying is performed airtemperature and air-flow rate are critical variables.

1.28 For ultrasonic cleaners, the frequency, amplitudeand power are critical variables. For cleaningefficacy the following parameters may also beincluded: water temperature, detergent type anddetergent concentration.

1.29 In all cases, the duration of each process stage

should be determined with sufficient accuracy toensure that consecutive cycles have the sameefficacy.

Assessment of workload and throughput

1.30 Advice on equipment numbers and instrumentthroughput is included within Health BuildingNote 13 Sterile services department.

Rigid endoscopes

1.31 Many rigid endoscopes and most of the reusablesurgical accessories used for minimal access therapy(MAT) can withstand steam sterilization and maybe processed through washer-disinfectorsemploying a thermal disinfection stage to makethem safe to handle during packing etc.

1.32 The washer-disinfector should be designed oradapted to ensure that during the flushing,cleaning, disinfecting and drying stages, processfluids (including drying) flow though the lumen(s)of the device.

1.33 Many washer-disinfectors can be equipped withdedicated load carriers to process rigid endoscopes,gas cannulae etc. There are also a number of


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dedicated endoscope cleaners including ultrasoniccleaners.

1.34 The capacity of the washer-disinfector should be

assessed on the number of items of each type thatcan be processed in a single load.

Powered devices

1.35 Some powered devices rely on the flow of apressurised fluid or compressed air for operation(for example, dental handpieces, phaco handpieces,orthopaedic saws and drills). If such devices are tobe processed through a washer-disinfector and theinternal surfaces are to be flushed, they should beconnected via dedicated connectors to ensure that

process fluids flow through the lumen(s) of thedevice during the flushing, cleaning anddisinfection stages. Flow and pressure throughlumens should be in line with the manufacturersrecommendations for the device. Specialistfiltration of process fluids passed through finelumens and powered devices may be necessary toavoid adverse effects on their performance.

Specification and contract

Introduction

1.36 This section discusses general specifications forwasher-disinfectors and the steps to be taken ininviting tenders and issuing a contract.

CE marking

1.37 Washer-disinfectors are covered by a number ofEuropean Directives and are thus required to be inconformance. Relevant Directives include but arenot restricted to: Medical Device Directive (93/42/EEC and 2007/47/EEC) Class II a,

Electromagnetic Compatibility Directive(2004/108/EEC), Low-voltage Directive (2006/95/EC), Pressure Equipment Directive (97/23/EEC)and the Machinery Directive (98/37/EEC and2006/42/EEC).

Preparing a specification

1.38 It is essential that the preparation of procurementspecifications be carried out by a qualified andcompetent person. The purchaser should employthe services of an AE(D) for this purpose.

1.39 Purchasers should refer to BS EN ISO 15883 Parts1 and 2, CFPP 01-01 Part B and the Particularspecification for washer-disinfectors included in

Appendix Awhen preparing a specification for awasher-disinfector.

Construction materials

1.40 Materials of construction should comply with therequirements of BS EN ISO 15883.

Integral air compressors

1.41 Washer-disinfectors might require a supply ofcompressed air for either the operation of valvesand powered door systems and/or during thedrying stage of the cycle.

1.42 When compressed air is intended to come intocontact with the washed and disinfected product

the compressed air supplied should be medicalgrade, i.e. it should be oil and particulate free (seeHealth Technical Memorandum 02-01 Medicalgas pipeline systems).

1.43 Built-in air compressors should be suitable for theduty imposed upon them.

Integral calorifiers and tanks

1.44 All integral calorifiers should conform to BS 853-1,and should be designed and constructed to allowthermal disinfection to be achieved throughout thecalorifier and associated pipework before water/steam can be supplied to the washer-disinfectorduring the thermal disinfection and subsequentstages.

1.45 Water tanks within the washer-disinfector shouldbe self-draining and located so that they arecleanable by the Operator and fitted with a draindown system which either works automaticallywhen the machine is switched off or which isaccessible to the User.

1.46 All tanks should be fitted with an overflow (see theWater Supply (Water Fittings) Regulations 1999).

1.47 When water is to be heated the heat source shouldbe controlled by a thermostat and it should employa heating medium as specified by the purchaser.The heat sources should be removable forreplacement or maintenance purposes.

Dosing systems

1.48 The washer-disinfector should be fitted with notless than two systems for controlling the admission

of chemicals (detergents, additives etc) and shouldbe provided with the facility for at least oneadditional dosing system to be fitted.


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1.49 Each dosing system should be provided with meansto adjust the volume admitted. Access to the meansof adjustment should require the use of a key, codeor tool. The means of adjustment can be manual or

automatic.

1.50 The stage(s) in the process cycle at which eachdosing system admits chemical to the washer-disinfector should be under the control of theautomatic controller.

1.51 Each dosing system should be provided with meansto determine the volume admitted and the timewithin the operational cycle when the admissionoccurred. This data should be available to theoperator.

1.52 Failure to admit the specified minimum volumeshould cause a fault to be indicated and a failureindication raised.

1.53 The accuracy and reproducibility of chemicaldosing systems should meet the requirements of BSEN ISO 15883-2.

1.54 The washer-disinfector should be fitted with asystem that will indicate when there is insufficientchemical(s) available for the next cycle and thatcycle should not be allowed to start.

Door controls

Control of manually operated doors

1.55 An explanation of the manual action required tolock the door should be provided for the Operator.In addition, if the unlocking procedure is not thereverse of the locking procedure, there should be anindication to the Operator of the manual actionrequired to unlock the door. The indication shouldbe clearly displayed either on the door or on itshandle or handwheel. Explicit instructions shouldbe displayed on the facing panel adjacent to thedoor or on the Operators control panel.

1.56 The door mechanism should be such that the forceto be applied by an Operator in order to either lockor unlock the door does not exceed 250 N at theintended point of grip.

Control of doors in a double-door washer-disinfector

1.57 In double-door washer-disinfectors, the control

initiating the automatic cycle should be at one endonly. When the loading door is closed and locked,it should not be possible to open the unloadingdoor until the washer-disinfector has completed a

successful operating cycle, i.e. without showing afault.

1.58 If a fault develops, it should only be possible to

open the loading door.1.59 It should not be possible for an Operator to open

or close a door at the opposite end of the washer-disinfector or for more than one door to be open atone time.

1.60 A visual display should be provided at both ends ofthe washer-disinfector to indicate when the cycle isin progress.

1.61 The indication cycle complete, or an equivalentindication, should be cancelled when the unloading

door is unlocked, and the loading door shouldremain locked until the unloading door has beenlocked again.

Loading systems

1.62 The washer-disinfector should be provided withcarriers to locate the load during the washing anddisinfection process. When interchangeable loadcarriers and baskets are provided, each load carriershould be capable of being fitted and removedwithout the use of tools. Washer-disinfector loadingsystems should be designed with regard to theManual Handling Operations Regulations 1992 (asamended).

1.63 When the washer-disinfector is supplied with asystem for supporting the load/transferring the loadinto and out of the chamber, the following shouldapply:

the load should be wholly supported andretained within the usable chamber space for theduration of the operating cycle;

the force required by the Operator, eitherdirectly or by the application of a mechanicaldevice supplied with the equipment, to removethe whole, or part, of the load from thechamber should not exceed 250 N when loadedand operated in accordance with themanufacturers instructions;

the load carrier should either be retained in thechamber by a mechanism which is only releasedwhen the transfer system is in place, or remainstable when withdrawn for a distance equal totwo-thirds of the chamber length, and be fittedwith a retaining device, which has to be releasedif the load is to be withdrawn further.


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1.64 Means should be provided such that the transfer ofthe load into and out of the chamber does notcause damage and wear to the chamber.

1.65 Systems which cause high levels of local stress, e.g.point loadings, might also initiate corrosion instainless steel materials.

1.66 The system used to support the load should beconstructed from durable, corrosion-resistantmaterials and should withstand, without damage,the environment within the chamber.

1.67 The system used should neither prevent theattainment of the pre-set cycle variables nor the freedrainage of water from the load and the penetrationof water/steam into the load. The load carrier(s)

should be designed so that they cannot be mis-positioned in a manner that will prevent suchattainment.

1.68 Any accessory used for handling the load which canbe used outside the washer-disinfector (e.g. atrolley) should remain stable when it is supportingits maximum design load and a force of 250 N isapplied horizontally in any direction to the highestpoint of the load or accessory.

1.69 The trolley should be designed to allow the

operator to align the trolley with the washer-disinfector for ease of loading and unloading.

1.70 The trolley should be provided with means tocollect liquid residues from the load to preventthese from dripping onto the floor. The meansprovided should be detachable for cleaning anddisinfection in a washer-disinfector or, wherenecessary sterilization at 134137C in a porous-load sterilizer.

1.71 The trolley should be provided with swivel wheelsto facilitate manoeuvring.

1.72 The trolley should be provided with a parkingbrake.

1.73 The trolley should be designed to secure the loadcarriers on the trolley during loading andunloading, and while traversing a gradient at aslope of up to 1 in 20.

1.74 Trolleys intended for use with single door machinesshould be designed and constructed to facilitatecleaning and disinfection of the trolley between usefor dirty and clean loads.

1.75 Load conveyors outside the washer-disinfector thatare intended to, or might reasonably be expectedto, come into contact with soiled/contaminated

goods should be designed and constructed to beeasy to clean and disinfect.

Cleaning the washer-disinfector

1.76 The design, construction and operation of thewasher-disinfector should ensure that during theprocess the surfaces of the chamber and the loadcarrier presented to the operator are cleaned anddisinfected.

1.77 For manually filled and emptied cleaning machineswith no disinfection cycle, for example stand-aloneultrasonic cleaners, the manufacturer should adviseon the cleaning/disinfection method.

Steam

1.78 Steam may be used in a heat exchanger as a sourceof indirect heating for water or air to be used in thecleaning, disinfection or drying stages of a washer-disinfector operating cycle.

1.79 Steam may also be used to heat process waterdirectly, or to heat the load directly during thethermal disinfection stage, and for this purposemay be supplied either with an integral steamgenerator or from an external (mains) supply.

Steam for indirect heating1.80 Steam heat exchangers used for heating water or air

may be of the shell, tube or plate design. In allcases, the steam supplied should be substantiallyfree from non-condensable gases and free from oilsince these contaminants seriously impair theefficiency of the heating process. The effect of thinfilms of air on the surface of the heat exchangermay increase heating costs by 25% or more.

1.81 The steam service should be designed to meet themaximum demand of the washer-disinfector, orbank of washer-disinfectors, while keeping the fallin pressure before the final pressure reducingsystem to no more than 10%.

1.82 Except for vertical rises between floors or atintermediate points on long runs, the pipeworkshould have a continuous fall such that anycondensate flows by gravity in the same direction asthe steam. Air vents and steam traps should befitted at each vertical rise.

1.83 The condensate discharge system should be sized to

ensure that the high volume of condensate foundduring the initial stages of heating can bedischarged without waterlogging the heatexchanger.


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1.84 When the steam supply pressure at the inlet to thewasher-disinfector exceeds the maximum valuespecified by the manufacturer, a pressure reducingvalve should be fitted to the supply pipe at least

3 m from the washer-disinfector.

1.85 Careful attention should be paid to the siting of allpressure relief valves to ensure that the washer-disinfector is properly protected.

1.86 Relief valves and their discharge pipes should belarge enough to prevent the pressure in the supplypipes rising to more than 10% above the designpressure for the heat exchanger. The discharge pipeshould terminate in a safe position outside thebuilding.

1.87 Steel and copper piping traditionally used for steamsupply are acceptable for this application.

1.88 Excessive moisture in the steam supply will impairthe heating efficiency of the heat exchanger and soshould be avoided.

Integral steam generators

1.89 Some washer-disinfectors are equipped with smallelectrically heated steam generators to raise steamto heat the load directly for thermal disinfection.

1.90 They may be of the open-boiler type, which are sodesigned and constructed that they are unable togenerate an internal pressure above atmosphericpressure. The design should ensure that, under asingle fault condition, for example obstruction ofthe steam discharge port, the boiler cannot becomepressurised.

1.91 Integral steam generators which are pressure vesselsshould be in accordance with PD 5500.

Condensate recovery

1.92 Condensate from steam heating systems (calorifiers,dryers) and steam traps on the pipeline is suitablefor recovery and should be returned to the steamgenerating plant when recovery is economicallyjustifiable. It should not be possible to contaminateinstruments if a failure of the heating coil occurs.

Compressed air

1.93 A compressed air supply might be required for theoperation of controls and air-drying. If the washer-disinfector does not contain an integral aircompressor, the air may be supplied from a pipedservice (mains supply) or from a local compressor.

Mains supply

1.94 If air is supplied by pipeline from a central air-compressor system, a Bourdon-type pressure gauge

conformant to BS EN 837 should be fitted on thesupply line to the washer-disinfector via anisolation valve.

1.95 A reducing valve, or other automatic device, shouldbe fitted to reduce the pressure of air delivered tothe washer-disinfector to no more than themaximum supply pressure specified by themanufacturer. A pressure relief valve will normallybe required.

Local compressor

1.96 When it is not practical to obtain compressed airfrom a mains supply, a dedicated compressed airsystem should be installed to supply the washer-disinfectors.

1.97 The compressors might be too noisy to install withthe washer-disinfector and might need to belocated in a dedicated location away from noisesensitive areas.

1.98 Components of the compressed air system thatrequire servicing and maintenance, such as dryers

and filters, should be located where they are readilyaccessible for service or exchange.

Air quality

1.99 The quality of air can be critical for someapplications and some washer-disinfectors willincorporate appropriate filters. When the purchaseris to be responsible for the provision of filtered airthe CP(D) should ensure that the quality of airavailable meets the washer-disinfectormanufacturers specification or the requirementsgiven below.

1.100 Air that could come into direct contact with theload, such as air used for drying the load or testingthe free-passage of lumens, should be:

oil-free (i.e. should have no more than 0.5 mgof oil per cubic metre of free air measured at1013 mbar and 20C; see ISO 554);

filtered to an efficiency of at least 95% whentested in accordance with BS 3928; and

free of bacteria (see Health Technical

Memorandum 02-01).1.101 Air for control purposes should be free of liquid

water, filtered to 25 m (5 m for precision


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controls) and lubricated with micro-fog oilparticles of 2 m or less.

Drainage

1.102 All effluent from a washer-disinfector is potentiallycontaminated and should be disposed of to themain drain. All washer-disinfector and associatedequipment should be connected to the drain in amanner that provides backflow protection andcomplies with local regulations.

1.103 Effluent can originate from each of the stages ofthe process, which may include:

a. flushing to remove gross contamination;

b. washing with detergent and/or enzymaticcleaners;

c. rinsing, with or without the addition of aneutralizer, rinse aid or instrument lubricant;

d. chemical disinfection or thermal disinfection;

e. post-disinfection rinsing;

f. drying particles.

1.104 Effluent from early stages (a) and (b) of the processmight contain significant concentrations oforganic contaminants and potentially infectiousmicroorganisms. Effluent from the middle stages(b), (c) and (d) can contain some organiccontaminants and potentially infectiousmicroorganisms and high concentrations ofprocess chemicals. Effluent from the latter stages(d), (e) and (f) can be at high temperatures (90C100C).

1.105 Effluent from washer-disinfectors should pass viaan air break into a tundish or tank before beingdischarged to drain. The air break should bepreserved at all times to prevent the washer-disinfector and its associated pipework beingcontaminated by reverse flow from the drainagesystem.

1.106 Where a tank supplies water to a pump on thewasher-disinfector, the overflow discharge from thetank should also include an air break.

1.107 The drainage system from the installation shouldbe trapped and designed to pass the flow rate ofwater, air and condensed steam specified by themanufacturer, with account taken of the peak

output during the operating cycle.1.108 The drainage system should be designed to pass

and maintain in suspension the solids removed

from the load during the flushing process. Theminimum diameter of the drainage system shouldbe greater than the maximum diameter of the mostrestricted section of the discharge from the washer-

disinfector chamber.

1.109 Means should be provided to prevent, as far aspossible, flash steam being liberated into theatmosphere or causing condensation on electricalequipment.

1.110 The discharge temperature from a washer-disinfector may be as high as 95C.

1.111 The materials used for the construction of thedischarge system should be chosen to withstandtemperatures up to 100C.

Hazardous effluents

1.112 The discharge of soil from washer-disinfectorsshould be regarded as being no more, but no less,hazardous than the discharge from any othersanitary appliance, e.g. a WC.

1.113 The discharge of process chemicals, includingdetergents and microbicides, may require specialattention. The local water undertaking should beconsulted before such chemicals are dischargedinto the drainage system, as it may be necessary toneutralize or inactivate them before discharge.

1.114 A sealed and vented drain should be used for thedischarge of chemicals with a significant vapourpressure, determined at the maximum attainabletemperature of effluent in the drain, which may behazardous to health or a nuisance. Possiblebackflow from the drain should be prevented bythe inclusion of a check valve and a vacuumbreaker.

Machine ventilation

1.115 Washer-disinfectors are often run under a slightnegative pressure to minimise the potential for thedischarge of aerosols into the environment.

1.116 Washer-disinfectors not equipped with an airextract system may require siting under anextraction hood. The capture velocity in thevicinity of the process is a design issue based on alocal assessment via design consultation. Theadvice of a specialist should be sought in designingthe ventilation system.

1.117 Additional guidance is given in Part B of HealthTechnical Memorandum 03-01 Specialisedventilation systems in healthcare.


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compounds. Use of a rinse-free cycle for laryngealmasks may be considered.

1.130 The chemical additives used should be readily

removed from the load items by rinsing with waterand should be biologically compatible with theintended use of the load items. Chemical additivesthat are intended to persist on the surface of itemsprocessed through the washer-disinfector (e.g.lubricants) should be biologically compatible withthe intended use of the load items.

Compatibility with the quality of water

1.131 The activity of many detergents and disinfectantsare seriously impaired by hard water.

1.132 Detergent formulations intended for use only withsoft water might give rise to precipitation if usedwith hard water, particularly at elevatedtemperatures. Once this precipitation has occurredon the surfaces of the washer-disinfector or theload it is particularly difficult to remove (seeparagraph 1.129, Compatibility with the items tobe processed).

Compatibility with other chemical additives

1.133 The additives used should be both compatible

with other chemicals used in the same processstage and, as far as may be practicable, with thoseused in preceding and subsequent stages tominimize the adverse effect of any carryover.

Compatibility with subsequent decontaminationprocesses

1.134 Chemical additives that might persist on thesurface of items processed through the washer-disinfector should be compatible with anysubsequent decontamination process that might be

required, such as terminal sterilization. An in-process instrument lubricant that deposits alubricant film on all surfaces of the instrumentshould only be used if it has been demonstrated tobe compatible with any subsequent sterilizationprocess.

1.135 The specified concentration of chemical additivesshould be attained in order to ensure effectiveprocessing. Too little will impair the process, whiletoo much is wasteful, might impair the processand might contribute to unacceptably high

residual levels.1.136 Suppliers of chemical additives should provide

product data sheets and material safety data sheets

for the products supplied. These should includedetails of biocompatibility studies. Referenceshould be made to local COSHH provisions.

1.137 Suppliers of chemical additives normally providedetails of the analytical methods that can be usedto detect residual concentrations of product. Thesensitivity of the method should be sufficient todetermine the presence of the compound belowthe level at which any adverse biological reactionwould be determined.

Detergents

1.138 For most applications, mild alkaline detergents inthe pH range 8.011.0 are preferred. Alkalinity

improves the efficacy of detergents both byenhancing their inherent cleaning capabilities,neutralizing and helping to remove acid soils,emulsifying oils and fats and peptidising proteins,and by synergistic action with other detergentcompounds. Many surfactants work better in thepresence of alkaline builders such as sodiumtripolyphosphate (STPP).

1.139 Cleaning agents for use in washer-disinfectorsshould be:

liquid (to facilitate accurate dispensing);

non-abrasive;

low foaming;

free rinsing;

biodegradable.

1.140 Detergents should not contain:

artificial colouring agents;

optical brighteners;

perfumes;

halides at an in-use concentration greater than120 mg/L;

fatty soaps, glycerine or lanolin;

toxic residue.

Enzymatic cleaners

1.141 Enzymes are organic catalysts through which thenormal metabolism of most living organisms takesplace. Although produced by living organisms they

are not themselves alive. They are large moleculeswhose steric configuration (shape) affords themthe ability to catalyse many reactions in the livingcell.


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a two layer carrier for small hollowware andinstrument trays;

a single layer carrier for large bowls, Edinburgh

trays etc; a rigid endoscope/MAT instrument/lumen

device carrier;

an anaesthetic accessories carrier;

sterilization containers;

carrier with dedicated connectors for powereddevices.

1.174 The load carriers should protect instruments frommechanical damage during the wash process andshould also orientate the instruments to facilitateproper cleaning providing, when necessary, a directconnection between the water flow and the lumenof the load item.

1.175 The specification for load handling equipmentshould include the provision of appropriate tablingto permit sorting of instruments and loading ofload carriers and, after processing, the unloadingof load carriers.

1.176 When double-door washer-disinfectors are used,means should be provided to return load carriers

from the unloading to the loading end. Where thispasses through the wall between the packing roomand decontamination room, there should be apass-through hatch with interlocked doors.

Test connections

1.177 Test connections should be provided to permit theconnection of thermocouples and pressuretransducers to be used during validation andperiodic testing.

1.178 When additional monitoring is provided, aseparate test connection should be provided foreach sensor to permit periodic verification of theinstalled system by comparison with a calibratedtest sensor.

Ultrasonic cleaners

1.179 The guidance given here assumes that the washer-disinfector is to be used to clean and disinfectmedical devices and that the essential requirementsof the EU directives are to be met.

1.180 Ultrasonic cleaners may be Type 1 or Type 2machines (ultrasonication may be integrated into aType 2 washer-disinfector). They are mainly used

as a preliminary cleaning stage prior to processingthrough a washer-disinfector.

1.181 Ultrasonic cleaners work by exposing the items to

be cleaned to high frequency sound waves in theliquid cleaning medium. The high frequencysound waves are generated within the liquid by thevibration of one or more surfaces of the bath,which is caused by one or more transducersbonded to the outer surface(s). The transducersconvert electrical power into vibrations of therequired frequency and amplitude. The highlyeffective cleaning action occurs as a result of thepenetrative agitation caused by cavitation, therapid formation and collapse of tiny bubbleswithin the liquid, which are generated by the high

frequency sound waves.

Applications

1.182 Ultrasonic treatment is particularly suitable forcleaning instruments of high-grade steel. Delicateinstruments such as micro-surgery instrumentsand dental instruments can be effectively cleanedwith little risk of damage.

1.183 Ultrasonic treatment is also particularly effectivefor cleaning instruments that have deep interstices

that may be contaminated with body tissues, forexample reamers, drills and burrs.

1.184 When combined with appropriate connection toan irrigation or flushing system, ultrasonicators arealso effective for cleaning internal and externalsurfaces of cannulated instruments.

1.185 Ultrasonic cleaners are less effective when used toclean plastic and similar readily compressiblematerials since they absorb much of the ultrasonicenergy.

Standard specifications1.186 Safety specifications for ultrasonic cleaners are

included in BS EN 61010-1.

Additional specifications

1.187 The ultrasonic cleaner should be fitted with meansto drain the tank with the cleaner in situ. The tankshould be free draining so that no pools of waterare left in the tank after draining.

1.188 The tank should be heated electrically and the

heaters should be thermostatically controlled.1.189 The ultrasonic cleaner should be fitted with a

timer to control the duration of exposure.


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1.190 The ultrasonic cleaner should have a lid; the lidshould be interlocked with the operating system toprevent normal operation if the lid is open andshould fit securely to prevent the emission of

aerosols when the cleaner is in operation.

1.191 The lid interlock should ensure that no part of theOperators body can be immersed in the ultrasoniccleaner during operation.

1.192 The ultrasonic cleaner should be effectivelyinsulated to prevent high frequency soundtransmission at a power that could cause a healthhazard. The casing and lid should provideadequate sound proofing so that harmonicfrequencies within the audible range are not

obtrusive.1.193 The manufacturer will normally recommend the

chemical additives (detergents/enzymatic cleaners)that are compatible with the process. Low foamingdetergents should be used. Liquid detergents usedfor washing dishes (washing-up liquid) are notsuitable.

1.194 The manufacturer is obliged to specify how thecleaner may be disinfected. This might be by theprovision of a high-temperature (for example80C) cycle option, or by means of a suitable

disinfectant solution. In the absence of guidancethe Microbiologist should be asked to advise on asuitable procedure.

1.195 The manufacturer is also obliged to specify thedegassing time(s) to be used on start-up and, whennecessary, between each load of instrumentsprocessed.

Wash cycle

1.196 The ultrasonic frequency used should be withinthe range 35 kHz 5 kHz and the energy inputused may range from 5 W L1to 20 W L1.

1.197 Ultrasonic cleaners can be designed to operate at asingle frequency, across a frequency range, or witha feedback control system claimed to adjust thefrequency in response to the loading conditions.

1.198 For medical applications aqueous solutions shouldbe used. Although ultrasonic cleaners containingaqueous solutions can be effective at temperaturesup to 90C it is normal practice to operate thosefor medical applications at temperatures between

ambient and 40C. This minimizes the rate ofcoagulation of proteinaceous material in thesoiling and is compatible with the use of enzymaticcleaners, many of which are rapidly destroyed athigher temperatures.

Type 1 and Type 2 ultrasonicators

Type 1 ultrasonicators

1.199A mechanical lifting device should be used whenthe ultrasonicator is intended to process heavy setsof instruments.

1.200 The load container, usually a wire mesh basket,should be of appropriate size for the longestinstrument to be processed.

1.201 When it is intended to process micro-surgicalinstruments or instruments with fine points theload handling equipment should provide means ofretaining these in position so that the points arenot blunted by the impacts resulting from fine

mechanical shaking.

Type 2 (continuous process) ultrasonicators

1.202 Continuous process washer-disinfectors mayincorporate an ultrasonic cleaning stage within thecycle programme.

1.203 Ultrasonic cleaners are also available in continuousprocess format with a thermal disinfection stageand with the option to provide a hot air dryingstage.

1.204 Ultrasonic cleaners with a solvent drying stage areno longer commercially available since the solventsused were CFCs, which are now prohibited underthe Montreal Protocol.

1.205 If complex tabling or conveyors are required theseshould be specified, and preferably illustrated witha sketch plan, when seeking tenders.

1.206 When it is intended to process micro-surgicalinstruments or instruments with fine points theload handling equipment should provide means ofretaining these in position so that the points arenot blunted by the impacts resulting from finemechanical shaking.

1.207 The ultrasonic cleaner should be fitted with atemperature indicator; provision should be madefor a recorder to be fitted if requested by thepurchaser.

1.208 The ultrasonic cleaner should be fitted with anindicator to show the power consumption (inwatts), or electrical demand (in amps) of theultrasonic transducers; provision should be made

for a recorder to be fitted if requested by thepurchaser.


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2.8 The programmes of tests should be applied to allwasher-disinfectors where relevant. Details aregiven under the test schedules for particular typesof washer-disinfector.

Schedule of type tests and works tests

2.9 The manufacturer will carry out type tests onrepresentative samples of washer-disinfectors inserial production to demonstrate compliance of thewasher-disinfector design with BS EN ISO 15883Parts 1 and 2.

2.10 The manufacturer will carry out works tests oneach washer-disinfector before it leaves themanufacturing site to ensure that each washer-

disinfector meets the specification. These testsshould be as given in BS EN ISO 15883 Parts 1and 2 including any additional tests required by theUser and AE(D).

2.11 The manufacturer should make the results of typetests and works tests available to the purchaser onor before delivery of the washer-disinfector.

2.12 It may be necessary for the purchaser, or theirrepresentative, to visit the manufacturers works towitness works testing. The advice of the AE(D)should be sought.

Schedule of installation tests

Checks on ancillary equipment

2.13 Ancillary equipment should, whenever practicable,be installed and commissioned before validation ofthe equipment begins.

2.14 When the checks on ancillary equipment requirethe washer-disinfector to be in operation, theCP(D) should carry them out in co-operation with

the contractor for the washer-disinfector.2.15 The contractor for the equipment is not responsible

for the correct functioning of services and ancillaryequipment unless this was agreed in the purchasecontract.

Engineering services

2.16 Checks should be made for the following services:

a. the engineering services should be installedcorrectly, should be adequate to meet the

demands of the decontamination equipment,should not leak and all necessary isolatingvalves/switches and test points should beinstalled;

b. the drains should remove effluent effectivelywhen all plant in the vicinity, including thedecontamination equipment, is connected andoperating;

c. the water treatment plant (if fitted) shouldoperate correctly and the quality of watersupplied for each stage of the process should bein accordance with the specification;

d. the water economy system (if fitted) shouldoperate correctly;

e. the provision for storage, handling andconnection to the washer-disinfector for allprocess chemicals should meet the requirementsfor safe handling of potentially hazardous

chemicals;

f. the exhaust ventilation and/or condenser unitfitted to the washer-disinfector should beadequate to remove the hot, humid air evolvedfrom the washing, thermal disinfection anddrying and unloading processes;

g. for washer-disinfectors employing volatileprocess chemicals, the exhaust ventilationshould maintain the environmentalconcentration below any limit specified for

occupational exposure and the discharge shouldbe to a safe place.

Checks on washer-disinfectors

Preliminary checks

2.17 Check that the electrical equipment on theequipment is correctly connected to the electricalservice. Carry out the following electrical tests:

a. insulation resistance;

b. phase sequence (for three-phase installations);

c. polarity;

d. bonding and earth continuity;

e. emergency stop.

2.18 After the equipment has been installed, check thatthe following recommendations are met:

a. the manufacturer has supplied all thedocuments specified in the contract;

b. the equipment has been supplied and installed

in accordance with the contract;


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c. calibration verification certificates for themeasuring instruments and controller(s) on theequipment have been supplied;

d. no defects are apparent from a visual inspectionof the equipment;

e. all supports, bases and fixings are secure andwithout imposed strain from serviceconnections;

f. thermal insulation is in good condition andsecurely attached;

g. security and settings of door safety switches arein compliance with data supplied by themanufacturer;

h. keys, codes or tools required to operate lockedcontrols and control over-rides have beensupplied, operate correctly and only operate thecontrol for which it is intended; and cannotunlock controls on other machines in thevicinity;

j. loading conveyors and trolleys, load carriers andload baskets are effective and safe in use;

k. All appropriate connections for irrigation areavailable.

Functional checks

2.19 During an operating cycle, with an empty chamber,check that the following recommendations arefollowed (several cycles may be necessary tocomplete all the checks):

a. The selection of automatic or manual control isby key code or tool. The selection of one controlmode inactivates the other control mode.

b. Under automatic control, water, steam,compressed air or chemical additives cannot beadmitted into the chamber, and the operatingcycle cannot start until the door is closed(locked and sealed).

c. Under manual control the operator can advancethe cycle only sequentially through each stage.Any stages designed to remove chemicaladditives from the chamber and load cannot becircumvented.

d. Throughout the cycle the indicated andrecorded values of cycle variables are within the

limits specified by the manufacturer.

e. Throughout the cycle there are no leaks ofwater, steam aerosols, toxic chemicals, air, gas oreffluent.

f. There is no evidence of interference to or fromother equipment connected to the same services.

g. There is no evidence of electromagneticinterference to or from other equipment.

h. Operation and reading of all instruments appearto be satisfactory.

j. The temperature of surfaces routinely handledby the operator does not exceed those specifiedin Chapter 1, Design and pre-purchaseconsiderations.

k. The effluent temperature does not exceed thatspecified in Chapter 1.

2.20 At the end of the cycle check that the followingrecommendations are followed.

a. The door opening system cannot be openeduntil the cycle has been completed withoutcausing the cycle to abort and a fault/incomplete cycle indication produced, that is,the automatic controller has operated inaccordance with its specification.

b. For systems incorporating one or more cyclestages at pressures 200 mbar above or belowatmospheric pressure:

(i) the door opening system cannot be operateduntil the chamber has been vented toatmosphere and the chamber pressure iswithin 200 mbar of atmospheric pressure;

(ii) the door retaining parts cannot be releaseduntil the seal between the door and chamberhas been broken, and the chamber iseffectively vented to atmospheric pressure.

c. The door interlock system is either fail-safe or isfitted with at least two independent interlocks.Failure of one interlock, or any one service, doesnot allow the door to be opened whenconditions within the chamber would cause ahazard (for example, pressure in excess of200 mbar or unacceptable level of chemicalvapours).

d. The automatic controller has operated inaccordance with the parameter values

determined at validation.


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either thermometrically or microbiologically, andare in short supply and are extremely expensive;examples include fibre-optic endoscopes,videoscopes etc.

2.26 A surrogate device is a test piece designed andconstructed to emulate the characteristics of adevice to facilitate appropriate monitoring of thecleaning and disinfecting processes.

2.27 An example of a surrogate device might be a rigidendoscope emulated by a similar length of stainlesssteel tube of appropriate diameter and bore. Thesurrogate device can be constructed to incorporatethe appropriate temperature sensors and so that itcan be separated into sections to facilitate the

evaluation of residual test soil or survivors from amicrobial challenge.

2.28 The surrogate device should have similar geometryand thermal mass and, as far as practicable, shouldbe constructed of the same materials and with thesame surface finishes as the device it is designed toemulate.

2.29 When an instrument presents particular problemsin validation the manufacturer of the instrumentshould be requested to provide details of themethod by which they recommend that PQ studies

should be performed.

Cleaning efficacy tests

Representative soiling

2.30 Cleaning efficacy tests are intended to demonstratethe ability of the washer-disinfector to remove orreduce, soiling and contamination that occursduring normal use of reusable items to acceptablelevels.

2.31 Naturally occurring contamination showsconsiderable variation both in the nature andproportion of constituents and in the extent ofsoiling which can occur during use.

2.32 Test methods based on the detection of naturallyoccurring soiling are difficult to standardise andshow poor reproducibility due to:

variation in the composition of the soiling,which can affect the ease with which soiling isremoved;

changes in sensitivity of detection that canoccur due to variation in composition of thesoiling;

variation in the extent of soiling.

2.33 A number of methods exist for estimating theresidual levels of proteins on surgical instruments.

2.34 Common practice in the past has been to rely solely

upon visual inspection to detect unacceptable levelsof residual soiling. This method should not beused, as it has poor sensitivity, is very subjective andcan be greatly influenced by a number of factorsincluding the intensity and nature of theillumination in the inspection area.

Note

The development path for this guidance recognises thecurrent work in the piloting of high sensitivity post-decontamination protein quantification tests. As these

become validated and available, this guidance will beamended to incorporate their use.

Test soils

2.35 Artificial test soils are designed to simulate thenature of native soiling and to be equally or moredifficult to remove.

2.36 Appropriate marker substances should beincorporated to provide improved sensitivity ofdetection.

2.37 Soil tests may be used to aid determination ofloading levels.

2.38 Test soils avoid any hazard that might be associatedwith native soiling (for example blood-borneviruses), which can be of particular concern withthe more extensive handling necessary for testwork.

2.39 Worldwide, many different test soils have beenspecified for testing washer-disinfectors but theygenerally fail to meet the key criteria necessary for a

test soil. These criteria include: a chemically defined formulation (the

traditional soils use substances such as flour,wallpaper paste, fresh egg yolk, horse blood etcwhich introduce a significant variability);

a quantitative method of applying the test soilto the surfaces of all types of item to beprocessed;

a quantitative method of detection of soilingremaining after the washingdisinfection

process;


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validation with a known relationship to nativesoiling for ease of removal, relevant residuallevels etc;

safe to handle, easy and economical to use.

Standard test soils

2.40 Test soils are defined in ISO/TS 15883-5 asfollows:

Instrument type ISO/TS 15883-5 Annex reference

Surgical instruments Annex N see description below

Anaesthetic accessories Annex O

2.41 The procedures within the UK are described asfollows:

Typical test soil

Constituents

2.42 The following ingredients are required:

a. fresh egg yolk 100 mL;

b. defibrinated blood, 10 mL (horse or sheep);

c. dehydrated hog mucin 2 g.

Preparation and storage

2.43 Mix all the constituents together and agitate in astomacher to give a liquid of uniform consistency.

2.44 Use immediately or store in an air-tight containerat 2C to 5C for not more than one week.

Application and use

2.45 If the soil has been stored, allow it to equilibrate toroom temperature before use.

2.46 The following apparatus is required:

paintbrush, 25 mm in width, soft;

disposable gloves, for example latex; drainage tray.

Method of application

2.47 The method is:

a. Don the protective gloves. Apply the soil to thetest pieces by fully immersing the items it thesoil or, for larger items, applying an even coat ofsoil using the paint brush.

b. Allow excess soil to drain from the items and

allow them to dry at room temperature (15Cto 25C) for not less than 30 minutes and notmore than 2 hours.

Method of detection

2.48 Visual examination. There are alternatives available.The advice of the AE(D) should be sought.

Process residues

2.49 The nature and level of process residues that are ofconcern depend on the chemical additives andquality of water used during the process and theintended use of the washed and disinfectedproduct.

2.50 The water used for the process can give rise to anumber of chemical residues on processed items.The most obvious of these is limescale from hardwater.

2.51 The water used for the process might also give riseto contaminants of microbial origin. Bacterialendotoxins, primarily derived from the cell wall ofGram-negative bacteria, may give rise to adverse(pyrogenic) reactions when introduced into thebody.

2.52 Items intended for surgically invasive use or for thepreparation or administration of parenteral fluidsshould have suitably low levels of bacterialendotoxins.

2.53 The chemical additives used during the process(detergents, rinse aids etc) might not be completelyremoved by the rinsing process. The residual levelthat may be tolerated depends upon the nature ofthe chemical and the intended use of the product.The supplier of any chemical agent used willnormally provide data on the chemical compositionof the chemical agent and the biocompatibility ofthe components of the chemical agent. Thesupplier will also normally provide details of themethod of detection, which can be used todetermine whether processed items are free from

residuals at the specified levels.

Disinfection

Thermometric tests

2.54 Thermometric tests should be carried out for boththermal disinfection processes and chemicaldisinfection processes.

2.55 The requirements for thermal disinfection aredefined in BS EN ISO 15883 parts 1 and 2.

2.56 Normally, microbiological testing is notrecommended for thermal disinfection processes.


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Method

2.91 On completion of an operating cycle to test thecleaning efficacy by processing a full load

contaminated with an appropriate test soil, placethe sampling tube into the water trap and remove asample for examination.

2.92 Examine the water sample from the trap forresidual test soil using the detection methodappropriate to the test soil.

Results

2.93 The water in the trap should be free from residualsoil at the same level of detection as that specifiedfor the load items. Residual soil in the trap can

present an infection or recontamination hazard.

Estimation of dead volume of pipework

2.94 Residual water that does not drain from theinternal pipework of the washer-disinfector mightprovide an environment for microbial growth; thesemicroorganisms might then be available to re-contaminate the disinfected load.

2.95 This test is intended primarily as a type test butmight also be of value as an operational test orwhen investigating microbial contamination

occurring in a washer-disinfector.2.96 The test should only be carried out once the checks

for free drainage recommended in paragraph 2.83,Free draining (tanks, chamber, load carriers,pipework)have been satisfactorily completed.

Apparatus

2.97 Volumetric measuring vessels of appropriate sizeshould be used.

Method

2.98 Ensure that the pipework of the washer-disinfectoris dry (either following disassembly and re-assemblyor purging with dry compressed air for not lessthan 30 min), then flush with a known volume ofwater (simulating the flow that would occur innormal use).

2.99 Measure the volume of water discharged and thedead volume, estimated as the volume retained,calculated from the difference between the twovalues.

2.100 When the washer-disinfector has two or morepipework systems that are entirely separate (e.g. forflushing water, wash water, rinse water or chemical

disinfectant solution) each system may be testedseparately.

Results

2.101 The volume of retained water should be less than1% of the volume of water used.

Venting system

Steam venting

2.102 For washer-disinfectors in which the load isheated/thermally disinfected by steam heating thechamber should be protected against a rise inpressure above the designed working pressure ofthe chamber and any discharge of steam should be

only from the vent provided.Apparatus

2.103 A pressure gauge should be used (if the washer-disinfector chamber is not already equipped with apressure gauge in a known state of calibration).

Method

2.104 Close and seal the chamber of the washer-disinfector in the manner specified by themanufacturer and start an operating cycle.Override the automatic controller to allow thecontinuous admission of steam to the chamber.Observe where steam is vented. Record themaximum value obtained on the pressure gauge.

Results

2.105 Steam discharge should occur solely through thevent. The recorded value for the pressure withinthe chamber should not exceed the specifiedworking pressure or, for a chamber designed towork at atmospheric pressure, 200 mbarg.

Load contamination from ductwork2.106 The evolution of water vapour from the chamber

during the washing stage, thermal disinfectionstage and drying stage can result in condensationoccurring in the ductwork and in the condenser (iffitted). The ducting is commonly arranged toallow this condensate to drain back into thechamber. Should this condensate becomecontaminated there is a risk that it couldcontaminate the load. The test is designed toestablish that any condensate draining back into

the chamber will not contact the load. The test isintended for use both as a type test (and as such isa requirement of BS EN ISO 15883-2) and as aninstallation or operational test.


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unexpectedly heavy demand might be placed uponthe water supply.

2.126 There are three methods that may be used for

determining the volume of water used. Themethod should be chosen on the basis of which ismost convenient for the particular installation.

Apparatus

2.127 A water flow meter (or volumetric measuringequipment) should be used.

Method

2.128 Fit a water flow meter in each of the water supplypipes, consecutively or concurrently, anddetermine the volume used by comparison of the

reading before and after each stage of the processcycle. Operate the washer-disinfector with thechamber empty, apart from the chamber furniture.Follow the water meter manufacturers instructionsfor installation. Pay particular attention to thelength of uninterrupted straight pipe required oneither side of the meter.

2.129 When the washer-disinfector is supplied from areadily accessible tanked supply interrupt themake-up to the tank and mark the water level.Determine the volume of water required to restore

the level after an operating cycle stage by theaddition of a measured volume of water.

2.130 For those washer-disinfectors which discharge allthe water from each stage at the end of each stage,obtain a suitable estimate of the volume used byvolumetric measurement of the discharge from thedrain.

Results

2.131 The volume of water used for each stage of thecycle should be within 5% of the volume

specified by the manufacturer.

Doors and door interlocks

Cycle start interlock

2.132 The interlock should prevent a cycle being startedwith the door open.

Method

2.133 Leave the doors open and unlocked. Ensure thatall services are connected. Make an attempt to

initiate an operating cycle.2.134 Close and lock the doors and make a further

attempt to initiate an operating cycle.

Results

2.135 It should not be possible to initiate a cycle with thedoor(s) left open. With the door(s) closed it should

be possible to initiate an operating cycle.

In-cycle interlock

2.136 An interlock is required to ensure that the door(s)cannot be deliberately or inadvertently openedwhile the washer-disinfector is in operation.

Method

2.137 Close and lock the door(s) and start the operatingcycle. While the operating cycle is in progressattempt to unlock each of the doors. Wherepracticable, visually inspect the interlocks to verifyengagement before attempting to open the door.

Results

2.138 In these circumstances it should not be possible tounlock any of the doors.

Double-door washer-disinfectors

Method

2.139 Both during and between cycles, make attempts toopen either or both the loading door and

unloading door of the double-door washer-disinfector.

Results

2.140 It should not be possible to open the unloadingdoor after initiation of a cycle until a cycle hasbeen completed satisfactorily.

2.142 It should not be possible for both doors to beopened at the same time.

2.143 It should not be possible to open the loading dooruntil a cycle has been satisfactorily completed and

the unloading door has been opened and closed.

On sensor failure

Method

2.144 Disable each sensor in turn and attempt to openeach of the door(s). Where practicable, avoid theundertaking of checks during an operating cycle.

Results

2.145 In each case it should not be possible to open the

door(s).


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original mark from the second cylinder. Calculatethe detergent added from the second cylinder.

2.164 Repeat the test three more times; record the

volume added on each test.2.165 Care should be taken since many of the

concentrates used are irritant or corrosive. Watermight not be an acceptable substitute because, formany dosing systems, differences in viscosity canaffect the dispensed volume.

Results

2.166 The result of the first test should be ignored.

2.167 The mean collected volume from the final threetests should be within 10% of the nominal

dispensed volume.

Indication of insufficient chemical additives

2.168 The correct volume of chemical additive(s) for thecorrect functioning of the washer-disinfectorshould be used. The washer-disinfector should beequipped with means to ensure that a cycle is notinitiated when there is insufficient chemicaladditive remaining in the reservoir to completea cycle.

2.169 The test should be carried out for each chemicaldosing system on the washer-disinfector.

Method

2.170 Place a low level of additives in the dispenserreservoir and run repeated cycles.

2.171 Fill an otherwise empty container with sufficientchemical for more than two but less than fouroperational cycles. Run the washer-disinfector onthree consecutive cycles. Estimate the volumeremaining at the end of each cycle (pre-markedcontainer, dipstick, or weight).

Results

2.172 The washer-disinfector should indicate at thebeginning of the third or fourth cycle that there isinsufficient chemical remaining to complete acycle.

Water vapour emissions

2.173 Faulty or damaged door seals, or faulty condensers,can give rise to vapour emission into the workingarea and the leakage of potentially infectious

material from the washer-disinfector.

2.174 Excessive and persistent leakage carries the risk ofscalding the operator and causing deterioration ofwalls and their surface finishes.

Apparatus2.175 The following equipment should be used:

a. absorbent paper wipes (of a type which changecolour density when damp);

b. one or more mirrors 50 mm 50 mm or larger.

Method

2.176 Load the washer-disinfector, close the door andwipe the joints between the door and the doorsurround to remove any moisture. Carry out anoperating cycle.

2.177 Throughout the operating cycle use the mirror(s)to check if water vapour escapes from the door sealor from the condenser (if fitted).

2.178 At the end of the operating cycle, with the doorstill closed, use the absorbent wipes to wipe thejoints between the door and the door surround asclose as possible to the door seal. Examine thewipes for dampness.

2.179 A further four operating cycles should be run withthe checks described above being carried out onthe final cycle.

Results

2.180 There should be no misting of the mirror(s),which would be evidence of vapour emission, andno dampness of the absorbent wipes, which wouldbe evidence of vapour or liquid emission.

Instrumentation fitted to a washer-disinfector

Verification of calibration

2.181 The calibration of instrumentation and anyindependent monitor fitted to the washer-disinfector should be verified by comparison withcalibrated test instruments during steady stateconditions, for example the temperature duringthe disinfection hold period. Compliance to BSEN ISO 15883-1 clause 5.1217 should be met.

2.182 This may be carried out concurrently with othertesting, for example during the automatic controltest during quarterly periodic testing (seeparagraph 2.304, Automatic control test).


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Load carriers

2.183 Load carriers come in a variety of forms includingtrolleys, carriages and baskets. Their correct

functioning is essential to the successful outcomeof a washer-disinfector operating cycle. It isimportant that they cannot easily be misaligned,that they function correctly and that, whenapplicable, they make good connection withservice supply points in the chamber and with loaditems (when necessary).

Method

2.184 Verify by visual observation the alignment of loadcarriers, their connection to water, air or chemicaladditive supply in the chamber (when applicable)

and their connection to load items, for examplecannulated instruments (when applicable).

2.185 Check load carriers with rotary spray arms toensure that the spray arms are free to rotate, bothwhen the load carrier is empty and when fullyloaded.

Thermometric tests

2.186 Thermometric tests are carried out to verify theattainment of the specified conditions throughoutthe chamber and load during the operating cycle.Continuous process washer-disinfectors and multi-chamber washer-disinfectors in which the use ofrecorders with fixed sensors is impractical shouldbe tested using single channel data loggers that canbe processed through the washer-disinfector.Biological indicators should not be used as asubstitute for thermometric testing.

Chamber wall temperature

Apparatus

2.187 A temperature recorder, according to therecommendations given in the Decontaminationequipment: test equipment and materials sectionof CFPP 01-01 Part B, with not less than12 sensors should be used.

Method

2.188 Locate thermocouples as follows: one in eachcorner of the chamber, one in the centre of the twoside walls, one in the centre of the roof of thechamber and one adjacent to the temperaturesensor used as the reference sensor for chambertemperature.

2.189 Measure the temperature attained throughout fouroperating cycles, the first of which should be at

least 60 min since the machine was last used (acold start) and the final three with not more than a15 min interval between cycles (a hot start).

2.190 The washer-disinfector should be operated emptyexcept for chamber furniture (for example loadcarriers).

2.191 Multi-chamber washer-disinfectors may be testedwith each chamber tested consecutively orconcurrently. In the latter case eight sensors shouldbe used for each chamber.

Results

2.192 The results should be as follows.

a. The temperatures recorded on the surface of

the chamber should be wi

cfpp 01 01 partd final

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