www bzfxw com BRITISH STANDARD BS EN 867 5 2001 Non biological systems for use in sterilizers — Part 5 Specification for indicator systems and process challenge devices for use in performance testing[.]
BRITISH STANDARD Non-biological systems for use in sterilizers — Part 5: Specification for indicator systems and process challenge devices for use in performance testing for small sterilizers Type B and Type S The European Standard EN 867-5:2001 has the status of a British Standard ICS 11.080.10; 19.100 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW BS EN 867-5:2001 BS EN 867-5:2001 National foreword This British Standard is the official English language version of EN 867-5:2001 The UK participation in its preparation was entrusted by Technical Committee LBI/35, Sterilizers, autoclaves and disinfectors, to Subcommittee LBI/35/3, Sterilization indicators, which has the responsibility to: — aid enquirers to understand the text; — present to the responsible European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; — monitor related international and European developments and promulgate them in the UK A list of organizations represented on this subcommittee can be obtained on request to its secretary Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Find” facility of the BSI Standards Electronic Catalogue A British Standard does not purport to include all the necessary provisions of a contract Users of British Standards are responsible for their correct application Compliance with a British Standard does not of itself confer immunity from legal obligations This British Standard, having been prepared under the direction of the Sector Policy and Strategy Committee for Materials and Chemicals, was published under the authority of the Standards Policy and Strategy Committee on 18 October 2001 Summary of pages This document comprises a front cover, an inside front cover, the EN title page, pages to 24, an inside back cover and a back cover The BSI copyright date displayed in this document indicates when the document was last issued Amendments issued since publication Amd No © BSI 18 October 2001 ISBN 580 38542 Date Comments EUROPEAN STANDARD EN 867-5 NORME EUROPÉENNE EUROPÄISCHE NORM August 2001 ICS 11.080.10 English version Non-biological systems for use in sterilizers - Part 5: Specification for indicator systems and process challenge devices for use in performance testing for small sterilizers Type B and Type S Systèmes non biologiques destinés être utilisés dans des stérilisateurs - Partie 5: Spécifications des systèmes indicateurs et dispositifs d'épreuve de procédé destinés être utilisés pour les essais de performances relatifs aux petits stérilisateurs de Type B et de Type S Nichtbiologische Systeme für den Gebrauch in Sterilisatoren - Teil 5: Festlegungen von Indikatorsystemen und Prüfkörpern für die Leistungsprüfung von KleinSterilisatoren vom Typ B und vom Typ S This European Standard was approved by CEN on 25 July 2001 CEN members are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the Management Centre or to any CEN member This European Standard exists in three official versions (English, French, German) A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Management Centre has the same status as the official versions CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom EUROPEAN COMMITTEE FOR STANDARDIZATION COMITÉ EUROPÉEN DE NORMALISATION EUROPÄISCHES KOMITEE FÜR NORMUNG Management Centre: rue de Stassart, 36 © 2001 CEN All rights of exploitation in any form and by any means reserved worldwide for CEN national Members B-1050 Brussels Ref No EN 867-5:2001 E EN 867-5:2001 (E) Contents page Foreword Introduction Scope Normative references Terms and definitions Requirements Test methods 12 Marking, labelling and packaging 16 Annex A (normative) Small steam exposure apparatus and steam for test purposes 17 Annex B (normative) Test cycles for evaluation of indicator performance in the porous load process challenge devices 19 Annex C (normative) Test cycles for evaluation of indicator systems for use in hollow load process challenge devices 22 Annex D (normative) Test cycles for evaluation of indicator systems for use in hollow load process challenge devices 23 Bibliography 24 EN 867-5:2001 (E) Foreword This European Standard has been prepared by Technical Committee CEN/TC 102 "Sterilizers for medical purposes", the secretariat of which is held by DIN This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorsement, at the latest by February 2002, and conflicting national standards shall be withdrawn at the latest by February 2002 This European Standard has been considered by CEN/TC 102 as one of a series of European Standards concerned with non-biological indicators used in the testing, monitoring and routine operation of sterilizers These standards are: EN 867-1 Non-biological systems for use in sterilizers – Part 1: General requirements EN 867-2 Non-biological systems for use in sterilizers – Part 2: Process indicators (Class A) EN 867-3 Non-biological systems for use in sterilizers – Part 3: Specification for Class B indicators for use in the Bowie and Dick test EN 867-4 Non-biological systems for use in sterilizers – Part 4: Specification for indicators as an alternative to the Bowie and Dick test for the detection of steam penetration prEN 867-5 Non-biological systems for use in sterilizers – Part 5: Specification for indicator systems and process challenge devices for use in performance testing for small sterilizers Type B and Type S In addition CEN/TC 102 Working Group has prepared a series of European Standards describing biological indicators for use in sterilizers These European Standards are: EN 866-1 Biological systems for testing sterilizers and sterilization processes – Part 1: General requirements EN 866-2 Biological systems for testing sterilizers and sterilization processes – Part 2: Particular systems for use in ethylene oxide sterilizers EN 866-3 Biological systems for testing sterilizers and sterilization processes – Part 3: Particular systems for use in moist heat sterilizers EN 866-4 Biological systems for testing sterilizers and sterilization processes – Part 4: Particular systems for use in irradiation sterilizers EN 866-5 Biological systems for testing sterilizers and sterilization processes – Part 5: Particular systems for use in low temperature steam and formaldehyde sterilizers EN 866-6 Biological systems for testing sterilizers and sterilization processes – Part 6: Particular systems for use in dry heat sterilizers EN 866-7 Biological systems for testing sterilizers and sterilization processes – Part 7: Particular requirements for self-contained biological indicator systems for use in moist heat sterilizers EN 866-8 Biological systems for testing sterilizers and sterilization processes – Part 8: Particular requirements for self-contained biological indicator systems for use in ethylene oxide sterilizers ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ The annexes A, B, C and D are normative According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countries are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom EN 867-5:2001 (E) Introduction The indicators and process challenge devices described in this European Standard are intended specifically for use in carrying out tests on small steam sterilizers, Type B or Type S prEN 13060 Parts and specify requirements and tests for small steam sterilizers Type B which are intended to process solid products, hollow products, and porous products any of which may be wrapped in one or more layers of sterilization grade packaging materials (see EN 868) and for small steam sterilizers Type S which may also be specified by the manufacturer of the small steam sterilizer as intended to process hollow products and/or porous products Small sterilizers unable to accommodate a sterilization module (600 mm x 300 mm x 300 mm) cannot be tested using the tests described in EN 285:1996 for large sterilizers for wrapped goods and porous loads either because the chamber size is unable to accommodate the standard test packs or because the efficacy of the tests is impaired when the test pack occupies a large proportion of the chamber volume The indicator systems described in this European Standard are intended to be used, in conjunction with the appropriate process challenge device, to demonstrate the rapid and complete penetration of steam into the process challenge device The construction of the process challenge device and the performance of the indicator are designed to ensure that penetration of steam in the load within the sterilizer will provide adequate assurance that steam penetration will occur in routine loads Scope This European Standard specifies the performance requirements and test methods for non-biological indicator systems, including the process challenge devices within which they are intended to function, to be used for testing the steam penetration performance of small steam sterilizers, Type B or Type S where appropriate The test systems specified are intended for use only in small steam sterilizers Type B conforming to prEN 13060-2 and having a usable chamber space greater than 10 l and for small steam sterilizers Type S conforming to prEN 13060-4 also having a usable chamber space greater than l ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ Non-biological indicator systems and the associate process challenge devices are specified for various types of load The possible loads are considered in two classes: Porous loads, which can be wrapped or unwrapped, or hollow instrument loads, which also can be wrapped or unwrapped The relevant section of this European Standard on porous loads specifies the requirements for: – a standard process challenge device to be used in the small load test for porous loads in small steam sterilizers; – an indicator system for use in the porous load process challenge device An indicator for this purpose is a Class B indicator as described in EN 867-1 – an indicator employing an alternative process challenge device equivalent to the porous load process challenge device The relevant section of this European Standard on hollow instruments specifies the requirements for: – hollow load process challenge devices to be used to simulate hollow instrument loads as defined in prEN 130604; – an indicator system, for use in one of the hollow load process challenge device, for assessing steam penetration in a wrapped load of hollow instruments An indicator for this purpose is a Class B indicator as described in EN 867-1 The process challenge devices described in this standard are intended for use only in sterilizers of sufficient size to accommodate the process challenge device with no part of the process challenge device closer than 20 mm from the vessel wall; in the case of the porous load process challenge device the total internal volume of the vessel is not less than 10 l EN 867-5:2001 (E) Normative references This European Standard incorporates, by dated or undated reference, provisions from other publications These normative references are cited at the appropriate places in the text, and the publications are listed hereafter For dated references subsequent amendments to, or revisions of, any of these publications apply to this European Standard only when incorporated into it by amendment or revision For undated references the latest edition of the publication referred to applies (including amendments) EN 285:1996 Sterilization – Steam sterilizers – Large sterilizers EN 866-3 Biological systems for testing sterilizers and sterilization processes – Part 3: Particular systems for use in moist heat sterilizers EN 867-1 Non-biological systems for use in sterilizers – Part 1: General requirements EN 867-3:1997 Non-biological indicator systems for use in sterilizers – Part 3: Specification for Class B indicators for use in the Bowie and Dick test EN 867-4 Non-biological systems for use in sterilizers – Part 4: Specification for indicators as an alternative to the Bowie and Dick test for the detection of steam penetration prEN 13060-2 Small steam sterilizers – Part 2: Particular requirements and test methods for type B sterilizers, intended for the sterilization of wrapped solid, hollow and porous products prEN 13060-4 Small steam sterilizers – Part 4: Particular requirements and test methods for type S sterilizers, intended for the sterilization of products specified by the manufacturer of the sterilizer ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ EN 20187 Paper, board and pulps – Standard atmosphere for conditioning and testing and procedure for monitoring the atmosphere and conditioning of samples (ISO 187:1990) EN 20534 Paper and board – Determination of thickness and apparent bulk density or apparent sheet density (ISO 534:1988) EN ISO 3696:1995 Water for analytical laboratory use – Specification and test methods (ISO 3696:1987) EN ISO 5457:1999 Technical product documentation– Sizes and layout of drawing sheets (ISO 5457:1999) ISO 10012-1 Quality assurance requirements for measuring equipment – Part 1: Metrological confirmation system for measuring equipment Terms and definitions For the purposes of this European Standard, the definitions given in EN 867-1 and the following definitions apply: 3.1 hollow load devices having a minimum diameter of mm or greater and no point internally at a distance greater than 1500 times the minimum internal diameter from direct open connection with the surrounding environment EN 867-5:2001 (E) 3.2 process challenge device object which simulates the worst case of conditions for attainment of the specified sterilization conditions within the items to be sterilized NOTE The device is so constructed that a biological or non-biological indicator system can be placed within the device in the position which it is most difficult for the sterilizing agent to reach The design of the process challenge device depends on the nature of the goods to be sterilized and the sterilization procedure 3.3 total internal volume volume of water at 20 °C which would be required to fill the hollow load process challenge device, including the space which would, in use, be occupied by the indicator system 3.4 free capsule volume capsule volume excluding the volume occupied by the indicator system 3.5 indicator system volume volume of water at 20 °C which would fill a space bounded by the maximum external dimensions of the indicator system 3.6 capsule volume internal volume of that part of the hollow load process challenge device intended to accommodate the indicator system determined as the volume of water at 20 °C which would be required to fill the capsule Requirements 4.1 General 4.1.1 The requirements of EN 867-1 shall apply ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ 4.1.2 Samples of non-biological indicators shall be conditioned in accordance with EN 20187 prior to testing for performance 4.1.3 The combination of process challenge device and indicator system shall be specified as providing a test system for either a porous load (see 4.2, 4.3 and 4.4) or a hollow instrument load (see 4.5 and 4.6) 4.1.4 When used in accordance with the manufacturer's instructions the indicator system, in combination with any specified process challenge device, shall provide indication of failure to attain steam penetration with a sensitivity sufficient to ensure that a satisfactory result will give confirmation that steam penetration would be attained in a sterilizer load of the type specified 4.1.5 Indicator systems intended for use with re-usable user-assembled process challenge devices shall not visibly transfer indicator reagent to the material of the process challenge device during processing Pre-assembled process challenge devices and indicator systems intended for use with the single-use user-assembled process challenge devices shall not transfer indicator reagent to the material of the process challenge device during processing to an extent which impairs the utility of the product Compliance shall be demonstrated by visual examination after testing in accordance with the requirements of 4.3.3 and 5.3.2 as appropriate EN 867-5:2001 (E) 4.2 Process challenge device for porous load 4.2.1 The process challenge device for porous loads shall be a standardised test pack for assessing the performance in the sterilization of porous loads in small steam sterilizers 4.2.2 The pack shall be constructed from plain cotton sheets, bleached to a good white and each having an approximate size of 450 mm x 300 mm Edges other than selvage shall be oversewn, not hemmed 4.2.3 The number of threads per 10 mm in the warp shall be (30 ± 6) and the number of threads per 10 mm in the weft shall be (27 ± 5) -2 4.2.4 The mass per unit area shall be (185 ± 5) g m 4.2.5 The sheets shall be washed when new and when soiled During the washing process the sheets shall not be subjected to any fabric conditioning agent 4.2.6 After washing the sheets shall be dried and aired, but not ironed or calendered 4.2.7 Before use the sheets shall be stored, unfolded and well separated, for at least h in an environment at a temperature between 20 °C and 30 °C and at a relative humidity of 40 % to 70 % 4.2.8 After airing, the sheets shall be folded to approximately 110 mm x 150 mm and stacked to a height of approximately 120 mm after compressing by hand The pack shall be wrapped in a single sheet of the same fabric and secured with tape not exceeding 19 mm in width The total weight of the pack shall be (900 ± 30) g ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ NOTE When forming the pack, consecutive sheets should be stacked with the folded side alternating to ensure an even stack NOTE Packs which are not used within h of preparation can be stored until required, providing the environmental conditions are maintained within the limits specified above NOTE After use the sheets will become compressed When the weight of sheets used to form a stack 120 mm high exceeds 1000 g, the sheets should be discarded 4.3 Indicator systems for use in the porous load process challenge device 4.3.1 The indicator systems are intended for use in a standard test pack of the type specified in this standard (see 4.2) 4.3.2 The indicator system shall comply with the requirements of EN 867-1 and, in addition, the substrate on which an indicator reagent has been deposited shall be marked with the information "For use in small steam sterilizers" 4.3.3 The indicator shall comply with the requirements of EN 867-3:1997 except that: a) the indicator system shall be A6 size to EN ISO 5457:1999; replacing EN 867-3:1997, g); b) the standard test pack used for evaluation of performance requirements shall be in accordance with 4.2 of this European Standard; replacing EN 867-3:1997 annex L; c) the steam exposure apparatus shall be as described in annex A of this European Standard; d) the operating cycle(s) of the steam exposure apparatus shall be as described in annex B of this European Standard EN 867-5:2001 (E) 4.4 Alternative indicators equivalent to the porous load process challenge device test The indicator shall comply with the requirements of EN 867-4 except that for the purpose of demonstration of equivalence the performance shall be compared with thermometric monitoring of the porous load process challenge device test pack (see 4.2) and the operational cycle(s) of the steam exposure apparatus described in annex A shall be as described in annex B of this European Standard 4.5 Process challenge devices for hollow instrument loads (hollow load process challenge device) 4.5.1 Under the conditions of use, the materials from which the hollow load process challenge device is made shall not release any substances in such quantities that would constitute a health risk or which will adversely affect the performance of indicator systems with which it is intended to be used when tested in accordance with 5.1 NOTE For further information see EN ISO 10993-1 and ISO 14538 4.5.2 The pH of a hot aqueous extract shall be within the range 6,5 to 7,5 when determined by the method given in 5.1.1.2 NOTE Many non-biological indicator systems are dependent for their colour change on a change in pH, or undergo reactions in which the reaction rate is dependent on pH Materials which can leach acids or alkalis into indicator systems are not suitable for general use 4.5.3 The hollow load process challenge device shall be constructed of material which is neither porous nor permeable to air or steam under the conditions of use (see clause 5) 4.5.4 The material(s) of which the hollow load process challenge device is constructed shall not absorb water to any significant extent and shall not cause an increase in mass greater than % when tested as described in 5.1.1.3 Such water as can be absorbed shall: ｗｗｗ．ｂｚｆｘｗ．ｃｏｍ a) not cause dimensional changes sufficient to affect adversely the compliance of the hollow load process challenge device with the performance requirements of this European Standard or greater than a linear expansion of % when tested as described in 5.1.1.3; b) not be released during the sterilization process to an extent which would compromise the ability of the indicator system to demonstrate inadequate air removal when tested in accordance with 5.1.3 4.5.5 The materials of which the hollow load process challenge device is constructed shall withstand exposure to the sterilization process for which it is intended: a) without distortion, melting, corrosion or other failure which would impair its utility; b) without any change occuring in the severity of the test as a result of thermal exposure when tested as described in 5.1.5 4.5.6 When the hollow load process challenge device is also intended to be used with biological indicators (or inoculated carriers) the material shall not release any substance to such an extent that it can inhibit the growth of low numbers of surviving micro-organisms on a biological indicator or inoculated carrier when tested by the method described in 5.1.4 EN 867-5:2001 (E) Test methods 5.1 Determination of compatibility of materials from which the process challenge device is constructed 5.1.1 Leachables, water absorption and dimensional stability 5.1.1.1 For each material of which the process challenge device is constructed a separate test shall be conducted NOTE Tests in accordance with 5.1.1.2 and 5.1.1.3 can be carried out on the same sample 5.1.1.2 Take a sample of known weight (not less than 10 g) and surface area consisting of several small pieces, at least two of which shall be clearly marked with scratch marks 50 mm to 70 mm apart Place the sample in a flask, add a volume of distilled water grade in accordance with EN ISO 3696:1995 and equivalent to 10 times the weight of sample (± 0,5 ml), heat to near boiling, maintain at > 90 °C for (10 ± 1) min, cap with a guard tube containing CO2 absorbent material and allow to cool When the sample has cooled, measure and record the pH Retain the sample for compatibility testing with the indicator system (see 5.1.2) Carry out a blank determination with water to which no sample has been added The pH of the blank shall be between 6,5 and 7,5 for the test to be valid 5.1.1.3 Take a sample as described in 5.1.1.2 Measure and record the distance between the scratch mark on the two marked samples using a catherometer Place the sample in a flask with a volume of distilled water equivalent to 10 times the weight of sample (± 0,5 ml) and boil under reflux distillation for (120 ± 5) min, cap with a guard tube containing CO2 absorbent material and allow to cool Decant and retain the existing solvent Remove the sample blot dry to remove surface water and measure the marked pieces using a catherometer Record the results Calculate the change in length which should not be greater than % NOTE Increase in length can be due to absorption of water, decrease in length can be due to stress releasing effect of elevated temperature Weigh the sample and calculate the change in mass which shall be not greater than % 5.1.2 Effect of aqueous extract systems on non-biological indicator systems Place samples of the indicator system which are being tested for compatibility in the extract obtained in 5.1.1.3 and allow to soak at room temperatures (15 °C to 25 °C) for (120 ± 5) If no colour change is observed remove the samples, blot dry and immediately test for colour change by exposure to dry saturated steam in accordance with annex C Concurrent tests shall be carried out on indicator system not previously treated with hollow load process challenge device extract There shall be no discernible difference in response between the two groups of indicator system samples 5.1.3 Effect of water absorption on non-biological indicator systems When the results of 5.1.1.2 indicate that the hollow load process challenge device absorbs 0,1 %, or more, of its weight of water the following test shall be performed Fill a hollow load process challenge device with distilled water and then immerse in distilled water so that all internal and external surfaces are in contact with the water Heat the water to near boiling and monitor at a temperature greater than 90 °C for (120 ± 5) Remove the hollow load process challenge device; blow through with dry compressed air to remove internal moisture and wipe dry on external surfaces Dry the hollow load process challenge device at 55 °C to 60 °C for (60 ± 5) Seal the indicator system in the hollow load process challenge device and place the assembly in a hot air oven at (140 ± 2) °C (or the stated sterilization temperature for the indicator system + °C) for 30 Upon removal from the oven the indicator system shall show no change or only such changes as occurred on 12 EN 867-5:2001 (E) exposure to dry heat (see 5.2.1) 5.1.4 Effect on biological indicators Sterilize aliquots of the remaining extract obtained in 5.1.1.2 and the original distilled water (by autoclaving in sealed borosilicate glass containers at 121 °C for a sterilization holding time of 15 min) Use these to prepare two four-fold dilution series of a suspension containing approximately 10 B stearothermophilus spores conforming to EN 866-3 Maintain the dilutions for h at 15 °C to 25 °C, heat shock at 90 °C for 10 and then plate out x 25 each dilution onto Tryptone Soya Agar and incubate at (56 ± 2) °C for 36 h to 48 h Count all plates having between 20 cfu and 400 cfu Compare the results from the distilled water and the extract There shall be no adverse effect from the extract shown by there being no significant difference between the two samples at the 95 % confidence limit 5.1.5 Hollow load process challenge device resistance to sterilizing process The test shall be conducted in accordance with the test for physical properties of carriers in EN 866-3 5.1.6 Seal of demountable cap on process challenge device 5.1.6.1 Seal the hollow load process challenge device, as per instruction given by the manufacturer Connect the open end of the hollow load process challenge device lumen to a 50 ml syringe NOTE A suitable adaptor may need to be made to give a gas tight fit Place sealed cap under water in a suitable container and pressurise by expelling air from the syringe into the lumen of the hollow process challenge device Observe the seal No bubbles shall be visible Any bubbles of air escaping from the seal, or any other part of the hollow load process challenge device, indicate that the hollow load process challenge device is unsuitable 5.1.6.2 Repeat 5.1.6.1 using an oil bath with oil heated to the maximum specified operating temperature for the hollow load process challenge device e g 140 °C NOTE Gloves, face visor, and impermeable and non-absorbent protective clothing should be worn when conducting this test Again no bubbles shall be visible when air is injected into the hollow load process challenge device 5.2 Indicator performance 5.2.1 Dry heat tests 5.2.1.1 Test 5.2.1.1.1 The test shall be conducted using a dry heat oven capable of maintaining a steady temperature within ± K at a set temperature within the range 117,5 °C to 140 °C NOTE The relative humidity in the oven should be less than % throughout the period of the test 5.2.1.1.2 Place the indicator system in the oven, which shall have been stabilised at the required operating temperature (see 4.6.9) and subject to dry heat for the required exposure period After the required exposure, remove the indicator system and examine for colour change NOTE Several indicator system samples can be exposed simultaneously 5.2.1.1.3 The test shall be performed in triplicate 13 EN 867-5:2001 (E) 5.2.1.2 Test 5.2.1.2.1 Fit the indicator system in combination with its specified test load (the indicator) with a temperature sensor to monitor the temperature of the indicator system and subject it to dry heat at (140 ± 2) °C to determine the time required for the indicator to reach 134 °C This time is the heat-up time NOTE Indicators intended for use only at a sterilization temperature of 121 °C can be subjected to (130 ± 2) °C and the time required to attain 121 °C is determined 5.2.1.2.2 Dry new samples of the indicator system in combination with its specified test load (the indicator) to constant weight at a temperature greater than 100 °C or by equivalent means at a lower temperature using a suitable desiccant 5.2.1.2.3 Transfer the dried indicators to the oven without undue delay and in a manner which will prevent rehydration of the indicator and subject them to dry heat at (140 ± 2) °C for ((heat-up time) + 30) NOTE Indicators intended for use only at a sterilization temperature of 121 °C can be subjected to dry heat at (130 ± 2) °C NOTE Several test samples can be exposed simultaneously 5.2.1.2.4 The test shall be performed in triplicate 5.2.2 Dry saturated steam tests 5.2.2.1 The tests shall be conducted using the test apparatus described in annex A and the test cycles specified in annex C 5.2.2.2 Expose the indicator system to cycle 2, annex C and then examine for colour change There shall be no colour change or if a change occurs the change shall be such that it can not be interpreted as indicating attainment of sterilization conditions 5.2.2.3 Expose the indicator system to cycle 1, annex C and then examine for colour change The colour change shall be complete and shall correspond to the change described by the manufacturer as indicative of attainment of sterilization conditions 5.3 Performance tests on the hollow load process challenge device 5.3.1 General 5.3.1.1 The tests shall be carried out using the apparatus specified in annex A and the test cycles specified in annex D 5.3.1.2 For each of the tests specified below the hollow load process challenge device shall contain, within the capsule, a compatible indicator system (see 4.6.1 and 4.6.2) which has previously been demonstrated to comply with the requirements of 4.6 5.3.1.3 The exposure temperature for the test cycles shall correspond to the sterilization temperature with which the indicator system is intended to be used 5.3.1.4 The sterilization holding time specified for the indicator system shall be not less than the "PASS" time given in Table for the corresponding temperature 14 EN 867-5:2001 (E) 5.3.2 "Pass" conditions After exposure of the process challenge device to test cycle 1, the indicator system shall show a clear change indicating attainment of sterilizing conditions Triplicate determinations shall be made Triplicate determinations shall be made 5.3.3 "Fail" conditions 5.3.3.1 The tests shall be carried out after satisfactory completion of the "pass" condition tests 5.3.3.2 Determine the operational limits for the air removal stage of cycle by progressive impairment of the air removal stages, in the manner specified in annex D, until the indicator system gives a clear indication that sterilization conditions were not attained Record the operational limits for these test cycles 5.3.3.3 Inoculated carriers complying with EN 866-3 and having the following characteristics shall be used: 1,4 5 x 10 9,5 °C D121value Population z-value 1,8 2,5 x 10 10,5 °C The dimensions of the inoculated carrier shall be compatible with the capsule of the process challenge device (see 4.5.9 and 4.5.10) 5.3.3.4 Place an inoculated carrier in the capsule of the hollow load process challenge device which is then exposed to a test cycle previously determined to attain sterilization conditions (see 5.3.3.1) 5.3.3.5 After exposure, culture the inoculated carrier in accordance with the manufacturers instructions 5.3.3.6 Triplicate determinations shall be carried out on sub-atmospheric (see annex D, cycle 1) air removal cycle with both the full specified sterilization holding time and with the sterilization holding time reduced by not less than 50 % 5.3.3.7 The hollow load process challenge device shall be acceptable if: – no growth is obtained from any of the inoculated carriers exposed to test cycles with the full sterilization holding time, and – growth is obtained from at least one of the inoculated carriers exposed to a test cycle with not more than 50 % of the sterilization holding time 15 EN 867-5:2001 (E) Marking, labelling and packaging 6.1 Indicator system for use in the porous load process challenge device The indicator systems intended for use in a porous load process challenge device of the type specified in this European Standard (see 4.2) shall be marked with the information "For use in small steam sterilizers" 6.2 Alternative indicators equivalent to the porous load process challenge device test The indicator shall be marked with the information "For use in small steam sterilizers" 6.3 Hollow load process challenge devices 6.3.1 The process challenge device shall be clearly and permanently marked with the symbol Hollow load process challenge device EN 867/5 Steam 6.3.2 The dimensions of indicator systems with which the hollow load process challenge device is intended to be used shall be clearly and permanently marked on the hollow load process challenge device 6.3.3 If the hollow load process challenge device is not intended for use over the temperature range 117,5 °C to 142,0 °C it shall be clearly and permanently marked with the temperature range within which it is intended to be used 6.4 Indicator systems for use in the hollow load process challenge devices 6.4.1 The instructions for use shall include details of any limitations concerning the design of the process challenge device with which the indicator system is intended to be used e g capsule dimensions (see also 4.6.2) 6.4.2 The indicator shall be labelled with details of the combination of temperature and time, in the presence of moisture, required to effect a clearly discernible colour change which shall be used to demonstrate attainment of satisfactory conditions for sterilization 16 EN 867-5:2001 (E) Annex A (normative) Small steam exposure apparatus and steam for test purposes A.1 General The steam exposure apparatus shall consist of a vessel with a usable chamber space between 10 l and 20 l, and a diameter not less than 180 mm The vessel shall be equipped with means of maintaining the internal surface of the chamber walls, other than the endplate and door at a controlled temperature within the range 115 °C to 140 C with a limit deviation of ± K The control system shall permit the operation of the specified test cycles (see annexes B, C and D) A.2 Instrumentation A.2.1 General The instrumentation shall comply with EN 285:1996, 6.2.1.3, 6.2.2.1, 6.2.2.2 A.2.2 Indicator, controller and recorder sensors A common system for indication, control and recording may be used provided that, a minimum of two sensors are employed for each location and variable to be considered and, that the system is self monitoring such that any error in the measured variable in excess of the accuracy specified (see A.2.1) shall result in the indication of a fault A.2.3 Calibration The equipment used for measurement of temperature and pressure shall be in a known state of calibration which shall be carried out and documented in accordance with ISO 10012-1 This shall include verification of calibration before and after each series of tests A series of tests shall comprise all the tests required to investigate conformity of a product with this standard Test results obtained after satisfactory verification of calibration but for which subsequent verification of calibration demonstrates that test equipment was outside specified limits shall not be used for demonstrating conformity with this European Standard A.3 Cycle control A.3.1 Steam control Means shall be provided to enable the steam in the vessel to be maintained at the selected operating pressure with a limit deviation of ± kPa A.3.2 Air detector If an air detector is fitted isolation of the air detector from cycle control shall be a cycle program option A.3.3 Signals Means shall be provided to generate signals capable of being used to automatically initiate the operation of ancillary equipment (e g air injection apparatus) on attainment of a programmable value for temperature at the reference 17 EN 867-5:2001 (E) measurement point of the chamber temperature, chamber pressure, or elapsed time at any chosen point during the air removal, steam admission, or hold stages A.4 Operating cycle: Stages and control options required The automatic controller shall provide means to select and adjust each of the following cycle stages: a) Air removal: To effect the initial stages of air removal, a pressure of 4,5 kPa or less shall be attainable This shall be followed by alternate steam admission and evacuation of the chamber The pressure range shall be adjustable to provide both sub-atmospheric and super-atmospheric pulsing The number of pulses shall be adjustable to provide the option to select between pulse and not less than 10 pulses; b) Steam admission: To pre-set exposure conditions (see annexes B, C and D); c) Exposure time: The pressure shall be controlled throughout the exposure time within ± kPa of the set pressure d) Evacuation: To remove steam (thus ending the indicator reaction) and also to dry the load, an ultimate pressure of kPa or less shall be attainable e) Air admission: To equilibrate the chamber pressure with atmospheric pressure A.5 Control limits A.5.1 Pressure attained control points shall be capable of being attained reproducibly to a limit deviation of ± 0,3 kPa over the range kPa to 30 kPa and ± 1,0 kPa over the range 30 kPa to 385 kPa A.5.2 Elapsed time control points shall be capable of being attained reproducibly to a limit deviation of ± s over the range s to 60 A.5.3 Temperature attained control points shall be capable of being attained reproducibly to a limit deviation of ± 0,5 K over the range 50 °C to 145 °C A.6 Steam supply A.6.1 The steam supply shall comply with the requirements of EN 285:1996, 13.3.2 to 13.3.4 Particular attention shall be paid to the levels of non-condensable gases in the steam supply and to ensuring that the moisture content or superheating of the steam is within the specified limits even under the extremes of the steam demand generated by the steam exposure apparatus, and any other equipment connected to the same steam supply A.6.2 The condensate obtained from steam supplied to the chamber of the steam exposure apparatus shall comply with the following requirements unless the manufacturer can demonstrate that any of the specified contaminants, when present at higher concentrations, not influence the performance of the indicator or indicator system Conductivity: 15 pH: to NOTE The pH-value can be monitored by chemical colour indicator as paper strip or solution Other interfering substances e g phosphate, chloride, sulphate, oxidisable substances, shall be identified by the manufacturer and stated in the labelling 18