Guideline Hospital Waste Decontamination Equipment

Transcription

1 Ministry of Housing, Spatial Planning and the Environment Directorate General for Environmental Protection Guideline Hospital Waste Decontamination Equipment Rijnstraat 8 P.O. Box GX The Hague, The Netherlands Internal Postal Code 645 December 2006 VROM 7098 februari 2007

2 Contents 1 Preface 4 2 Introduction Sterilization or disinfection Batch versus continuous processing 5 3 Scope 6 4 Definitions 7 5 Process Decontamination agent Decontamination process Shredding waste and/or removing air Wetting and heating Decontamination Drying (when required) 10 6 Equipment General Process Monitoring, control, faults and maintenance 12 7 Validation Type test Works test Installation qualification (IQ) Operational qualification (OQ) Performance qualification (PQ) Report Requalification 16 8 Routine monitoring and release of processed waste Process documentation Release of processed waste 17 9 Literature 18 Annex 1: Rationale for the decontamination process parameters 19 Annex 2: Correlation between temperature and pressure in saturated steam 21 Annex 3: Validation Schematic representation 22 Annex 4: Persons involved in drawing up the guideline 22 Guideline Hospital Waste Decontamination Equipment Page 3/23

3 1 Preface Every health-care facility produces waste that contains pathogenic micro-organisms which makes it potentially hazardous for humans. This type of waste is referred to as hospital waste. In the Netherlands, hospitals are not allowed to discard hospital waste as normal industrial waste. Legal reasons aside (Wet Milieubeheer, Landelijk Afvalbeheersplan), a hospital may choose, for aesthetic reasons, to decontaminate hospital waste before transporting it to a regional waste incinerator. The requirements for the efficacy and reproducibility of the decontamination process of hospital waste show a strong resemblance to the requirements for the disinfection and sterilization of reusable medical devices. There are, however, two important differences: The level of contamination of the hospital waste is expected to be very high. There is no concern about the compatibility between the products that are decontaminated and the process; the process may be destructive for the products. It is common practice to collect injection needles in sharps containers and incinerate them in the Dutch central hospital waste incinerator in Dordrecht (ZAVIN). The ideal hospital waste decontamination equipment is able to render injection needles harmless and unrecognizable. Not all of the equipment that is currently available on the market is designed to process sharps. A manufacturer claiming that its decontamination equipment is able to process sharps is required to univocally substantiate its claim. The design and construction of hospital waste decontamination equipment vary considerably. For these reasons, not all of the requirements in Section 6 of this guideline may be applicable. Manufacturers shall provide a rationale for every requirement it does not deem applicable to its decontamination equipment. Moreover, manufacturers shall demonstrate that the decontamination process effectively and reproducibly disinfects or sterilizes the hospital waste. Guideline Hospital Waste Decontamination Equipment Page 4/23

4 1 Introduction 1.1 Sterilization or disinfection In the autumn of 2005, at the request of the Netherlands Ministry of Housing, Spatial Planning and the Environment, the RIVM conducted a study to establish which methods are suitable to decontaminate hospital waste. The study showed that disinfection or sterilization with moist heat is the most suitable method. Both the efficacy and reproducibility are high for moist heat processes that use hot water and/or saturated steam. Annex 1 provides a summary of the relevant parts of the study report. 1.2 Batch versus continuous processing Decontamination processes can be run in individual batches or continuously. The requirements in this guideline apply to both techniques. Guideline Hospital Waste Decontamination Equipment Page 5/23

5 2 Scope This guideline describes the requirements for the equipment and the process for the decontamination of hospital waste that use saturated moist heat. Readers are advised to contact the waste disposal service for possible additional requirements. It must be clear whether the output from a decontamination unit will be accepted by the waste disposal service before purchasing equipment. Note: It is not the intention of this guideline to exclude decontamination techniques that do not use saturated moist heat. For such techniques, this guideline can be used as a reference, whereby the applicability of each requirement in this guideline must be evaluated. Where necessary, manufactures will provide additional information confirming the requirements, and in particular, the requirements concerning the efficacy of the process. Guideline Hospital Waste Decontamination Equipment Page 6/23

6 3 Definitions For the purpose of this guideline, the following definitions apply: Decontaminate The processing of hospital waste using saturated moist heat in order to inactivate infectious agents; disinfection or sterilization. Decontamination process A series of (automated) actions carried out to decontaminate hospital waste, including pre-treatment (for example, conditioning and shredding) and post-treatment (drying). Decontamination time The time necessary to achieve the specified process efficacy under the defined process conditions. Disinfection The inactivation of the micro-organisms that pose a risk of infection. This does not necessarily mean all micro-organisms. Equilibration time The period which elapses between the attainment of the decontamination temperature at the temperature sensor of the process controller and the attainment of the sterilization temperature at all points within the load. Hospital waste Waste from maternity care, wound treatment, diagnosis and the treatment or prevention of diseases in humans and/or related examinations, the collection and disposal of which is bound by rules to prevent the spreading of disease and infection. This type of waste is categorized by Eural as category Installation qualification (IQ) The process of obtaining and documenting evidence that equipment has been provided and installed in accordance with its specification. Operational qualification (OQ) The process of obtaining and documenting evidence that installed equipment operates within predetermined limits when used in accordance with its operational procedures. Performance qualification (PQ) The process of obtaining and documenting evidence that equipment that is installed and operated in accordance with operational procedures consistently performs in accordance with predetermined criteria and thereby yields product that meets its specifications. Process Challenge Device (PCD) An item designed to constitute a defined resistance to a sterilization process and used to assess the performance of the process. Note: The item is designed to receive a biological or chemical indicator in the part that is most difficult to penetrate by the moist heat. The composition of the hospital waste may determine the design of the PCD. Guideline Hospital Waste Decontamination Equipment Page 7/23

7 Process parameter Specified value for a process variable. Process variable A condition in a sterilization process, changes in which alter microbicidal effectiveness. Examples: Time, temperature, pressure, concentration, humidity. Reproducible A decontamination process is reproducible when the critical process parameters in every process run are within the specified tolerances. Saturated moist heat a. Water vapour that is in a state of equilibrium between condensation and evaporation. Note: See Annex 2 for the mathematical correlation between the temperature and the pressure of water vapour. b. Liquid water with a temperature of at least 65 C. Self-decontamination cycle A decontamination cycle designed to decontaminate the internal parts of the equipment, which, during normal use, come into contact with the hospital waste being processed, in order to render these parts safe to handle for maintenance and repairs. Sterilization Validated process used to render a product free from viable micro-organisms. Temperature band The range of temperatures measured during the decontamination time, the minimum of which is the decontamination temperature and the maximum of which is specified by the manufacturer. Theoretical steam temperature The temperature of saturated steam calculated from the prevailing pressure. Type test A series of checks and tests for a particular design of decontamination equipment that demonstrate compliance with the requirements of this guideline. Note: This series of checks and tests is performed by the manufacturer before the equipment is marketed. The user of the equipment can use the data from the type test to determine whether the decontamination equipment is suitable for the intended purpose. Validation The documented procedure for obtaining, recording and interpreting the results required to establish that a process will consistently yield product that complies with predetermined specifications. Note: IQ, OQ and PQ are part of the validation process. See Annex 3 for a schematic representation of the relationship between the different procedures. Waste disposal service A legal entity that collects decontaminated hospital waste from the hospital. Works test A series of tests performed at the manufacturer s works to demonstrate that each decontamination apparatus complies with its specifications. Guideline Hospital Waste Decontamination Equipment Page 8/23

8 4 Process 4.1 Decontamination agent The decontamination equipment described in this guideline uses saturated moist heat to inactivate hazardous micro-organisms. Saturated moist heat can be used in the form of steam or liquid water, both of which are equally effective in the inactivation of micro-organisms. The hospital waste can either be submerged in hot water or be exposed to externally generated steam that is admitted into the decontamination vessel. Moist heat can also be generated from the water that is already present in the waste materials, for example, bottles of growth media from the laboratory, by heating the water with steam, micro-waves, compression, etc. It is essential that both moisture and heat are present on the surfaces to be decontaminated. In the event that some surfaces are not readily exposed to the moist heat, for example, in tubes and injection needles, additional means shall be used to make the surfaces accessible to moist heat. Common techniques to achieve this consist of shredding the waste or removing the air by vacuum, or a combination of both. Based on these principles, a range of technical solutions to produce an effective decontamination cycle for each of the specified types of hospital waste may be developed, each with its own advantages and disadvantages. The time and temperature combinations specified in Clause 6 for acceptable disinfection and sterilization processes are only valid for saturated moist heat as the decontamination agent (see also Annex 1). On the surfaces to be decontaminated, the measured temperature shall correspond to the theoretical steam temperature. Annex 2 provides the correlation between the temperature and the pressure of saturated steam. In the event that these criteria are not met, the moist heat will not be saturated and the decontamination times stated in Clause 6 will not be valid. In such cases, the manufacturer is required to demonstrate, for example, by microbiological testing, that the process is effective despite the nonsaturated conditions of the moist heat. 4.2 Decontamination process The decontamination process shall include, where appropriate, the following stages: 1. Shredding of the waste or air removal or a combination of both 2. Wetting and heating 3. Decontamination 4. Drying (when required by the waste disposal service) Note: These stages may not be clearly separated in all equipment and the order of stages may vary. However, it facilitates the evaluation of the efficacy and reproducibility of the process when the stages are clearly separated, especially when the decontamination stage has clear start and end points and is conducted at a single temperature for a defined period Shredding waste and/or removing air Shredding is an effective way of bringing moist heat into contact with all of the surfaces of the waste materials. Moreover, shredding decreases the volume of the waste and renders it unrecognizable. Shredders are designed to reduce the size of the items in the waste to particles of a specified size range, which is chosen to allow the penetration of moist heat to the surfaces to be decontaminated. The shredding of contaminated waste may, however, lead to the contamination of the working environment by expelling aerosols and airborne particles. The design of the decontamination equipment shall include the decontamination of the shredder during a routine cycle. The decontamination equipment shall also provide Guideline Hospital Waste Decontamination Equipment Page 9/23

9 the means to disinfect the shredder before maintenance or repair. The shredder s filling funnel shall be hermetically closed when the shredder is in operation. Any overpressure release vents shall be fitted with adequate air filters. A manufacturer of decontamination equipment with a built-in shredder that claims that the equipment is suitable to process injection needles is required to demonstrate that the size of the injection needles will be reproducibly reduced to the size specified by the manufacturer to enable the decontamination of the needles internal surfaces. Shredding of the waste is not a prerequisite for the effective penetration of moist heat. Air removal allows for the rapid and even penetration of moist heat in porous and hollow materials. Experience with the sterilization of medical devices shows that a fractionated vacuum is almost always necessary in order to remove air from hollow devices. The details of the pressures and stage times of the fractionated vacuum are specified by the manufacturer. The validation of the process shall demonstrate the effective penetration of moist heat. The test methods described in DIN use a standard hollow test item to demonstrate the penetration of moist heat in hollow items. Note: In equipment without a shredder, plastic materials may melt and form compact masses in which contamination is enclosed. This contamination is consequently shielded from moist heat during the decontamination stage. Infectious agents inside the melted plastics may not be inactivated. To prevent the release of these infectious agents, the decontaminated hospital waste must not be shredded or compacted in a press container. The waste with intact enclosed contaminants is deemed to be decontaminated Wetting and heating During this stage, the waste is wetted and heated. This stage is followed by the decontamination stage Decontamination During the decontamination stage the temperature shall be maintained minimally at the decontamination temperature, under saturated moist heat conditions Drying (when required) During the final stage of the process, moisture is removed from the decontaminated materials to the level specified by the waste disposal service. Guideline Hospital Waste Decontamination Equipment Page 10/23

10 5 Equipment 5.1 General a. The decontamination equipment shall fulfil all relevant European health and safety requirements. b. The decontamination equipment is preferably designed to decontaminate all possible items present in hospital waste, including lengths of tube, syringes, needles, suction bottles and growth media from the laboratory. Where relevant for the decontamination process, the manufacturer shall also specify the packaging of the waste. All limitations in the use of the equipment, (for example, the composition of the waste, needles yes/no, capacity, moisture content, packaging) shall be clearly stated by the manufacturer to the potential purchaser. c. The manufacturer shall provide the instructions for use, written in Dutch, in which the complete decontamination procedure is described, from loading the equipment with waste, to the release of the processed waste. The manufacturer shall also describe the procedures to be followed in case of an emergency shut down and/or equipment failure. d. Where applicable, the manufacturer shall specify the safety measurers for the operators and the working environment that are necessary during normal operation of the equipment and for emergency access while hospital waste is present in the equipment. e. The manufacturer shall provide schematic construction drawings, details of the process dynamics (including process variables and the limits of the process parameters) and detailed installation drawings (including a diagram of the locations of connectors and conduits of the external services, such as electrical power, steam, water, pressurized air) to the user. f. The manufacturer shall specify the required quality and quantity of the external services, (for example, electrical power, steam, water, pressurized air), drains, climate control, ventilation, etc. Such description shall include specifications for the connectors and fittings. g. The manufacturer shall have the results from the type test and works test, as per Clause 7.1 and 7.2., available for the user. The results from these tests shall demonstrate that the decontamination equipment is suitable to process the type of hospital waste specified by the manufacturer. After the installation of the decontamination equipment, an installation qualification and operational qualification shall be performed as per Clause 7.3 and 7.4. When these qualifications are performed by the manufacturer, the user shall be provided with the results. h. After the successful OQ, it shall be demonstrated by performance qualification as per Clause 7.5. that the decontamination equipment is suitable to effectively and reproducibly process the hospital waste provided by the user. The user will write a plan for the PQ and effectuate it. The decontamination equipment will only be released for routine use after successful completion of PQ (see Clause 7.6). i. The decontamination equipment shall be designed to prevent the uncontrolled emission of waste materials, fumes, aerosols and vapours, for example, hermetically sealed, operating at underpressure. All materials and substances that are emitted from the decontamination equipment during or at the end of the process shall be decontaminated. For example, air shall be filtered through a HEPA filter before venting, waste water shall be collected and thermally decontaminated or returned into the process. j. The manufacturer shall specify the skills of the operators and, where necessary, offer training. Guideline Hospital Waste Decontamination Equipment Page 11/23

11 5.2 Process a. For disinfection, the decontamination time shall be at least 15 minutes at 100 C. The microorganism to use in a microbiological qualification is Bacillus athropheus per DIN (formerly known as Bacillus subtilus var. globigii). b. For sterilization, the decontamination time shall be at least 30 minutes at 121 C or equivalent, for example, 7 minutes at 134 C, 20 minutes at 126 C, 2 minutes 143 C. Note: When microbiological qualification is required to assess the efficacy of the process, the decontamination time should correspond with the resistance of the biological indicator (NEN EN ISO parts 1 and 3). c. The decontamination process shall be reproducible. d. The stages of the decontamination process shall be univocally described. Preferably, only one decontamination program is available. If more than one program is available, the purpose of each program and the differences between the programs must be clear to the operator. e. Decontamination equipment shall be provided with a self-decontamination cycle to decontaminate all internal parts of the equipment that come in contact with the hospital waste and are therefore contaminated during normal operation. In addition to an automated self-decontamination cycle, the manufacturer shall provide the means to carry out a manually controlled self-disinfection cycle (for example, in the event the equipment fails). The manufacturer shall provide instructions how to perform the self-decontamination cycles. If the machine is equipped with a shredder, it shall be also be decontaminated. The efficacy of the self decontamination process shall at least be equal to a disinfection process for 15 minutes at 100 C under saturated moist heat conditions. f. Manual adjustment of the process parameters in the controller should be avoided. If the parameters can be manually adjusted, modification of process parameters shall only be possible by authorized persons using a special key, code or tool. g. At the request of the purchaser, the manufacturer will deposit the source code of the controller software with a third party, such as a solicitor, bank, etc., so that the source code will be available to the purchaser in case of bankruptcy. Details of the third party will be forwarded to the purchaser. h. Decontamination equipment that uses a vacuum to enable the penetration of moist heat into lengths of tube, needles, porous materials, etc., shall be constructed to allow the performance of an air leakage test, a helix test per EN867-5, and the Bowie & Dick test per D6102. i. Inspection hatches providing access to the internal parts of the decontamination equipment shall be monitored to prevent the start of a cycle when one or more hatches are open, and to abort a cycle when a hatch is opened during the cycle. 5.3 Monitoring, control, faults and maintenance a. For the purpose of validation, means shall be provided to allow the performance of multi-point temperature measurements in the hospital waste and the internal parts of the decontamination equipment. Note: Temperature measurements on the internal parts of the decontamination equipment are performed to demonstrate the efficacy of the self-decontamination cycle on, for example, the loading funnel, shredder, transport screws and stirrers. Decontamination equipment that operates at a pressure above atmospheric and/or uses a vacuum for air removal shall be fitted with a connector for one or more pressure transducers. Decontamination equipment provided with a shredder shall, for the purpose of validation and monitoring, allow for the introduction of probes, data loggers, biological indicators, etc. into the flow of shredded hospital waste after the shredder, for example, a hatch. b. The decontamination equipment shall be fitted with two independent temperature measurement systems. One system is used to control the process, the other is used to monitor and record process parameters (see also NEN EN 285: 2006, Clause 6.2.). Both systems shall, under the conditions of use and taking the ambient temperature, moisture, vibrations, etc. into account, not deviate more than 1 C from the decontamination temperature. Where applicable, the pressure shall be monitored and recorded. The pressure measurement system shall, under the conditions of use and taking the ambient temperature, moisture, vibrations, etc. into account, not deviate more than 4 kpa from the pressure of the decontamination temperature. The manufacturer shall state any other process variables that may affect the efficacy of the decontamination process, such as the rotation speed of a transport screw, that affect the decontamination time. These process variables shall be monitored and recorded. The manufacturer shall provide a rationale for the accuracy of the additional measurement system(s). Guideline Hospital Waste Decontamination Equipment Page 12/23

12 c. Where the recorded process parameters are presented as a graph, the resolution shall be sufficient to allow the data on the chart to be read and interpreted without the need for additional optical enhancement systems (such as magnifying glasses) or measuring tools (such as rulers). d. The recorded process parameters shall be indicated to the operator during the process. e. The decontamination equipment shall be fitted with a fault indication system. In the event of a fault, the cycle shall be terminated and the cause indicated to the operator. The meaning of the indications must be clear to the operator. Any text displayed or printed shall be in Dutch. Means shall be provided to bring the process towards a safe situation to allow for the removal of the waste. It must be presumed that the waste is still contaminated and shall be handled as such. f. For safety reasons, it shall be possible to manually terminate the cycle. Termination of the cycle shall be recorded by the process recorder. It must be presumed that the waste in the decontamination equipment is still contaminated and shall be handled as such. g. The manufacturer shall provide the means to safely remove the waste from the decontamination equipment or reprocess the load in case of untimely termination of the cycle, either after a manual cancellation of the cycle or as the result of a fault. h. In double-door decontamination equipment, an interlock system shall prevent that both doors are open at the same time and will ensure that that the unloading door can only be opened at the end of a successfully completed process. i. When required by the waste disposal service, the waste shall be dried to the specifications of the waste disposal service. j. The manufacturer shall provide a maintenance program and a maintenance protocol that guarantee continuous operation according to specifications. At least the following actions must be performed during maintenance: Check the state of the equipment; make sure all parts are free from corrosion, all indicators are functioning, moving parts are running, etc. Check seals, conduits, fittings, etc. for leakage. Check the proper functioning of safety parts, e.g. overpressure release valve, door locks and interlocks, temperature cut-outs, etc. Calibrate the sensors for process control, monitoring and recording. Where the decontamination equipment is provided with a built-in water treatment system or where it is connected to an external water treatment system, the maintenance of the water treatment system must be checked. Check, clean and replace filters. The replacement or repair of parts during periodic maintenance may necessitate a requalification of the decontamination equipment as per Clause 7.7. The manufacturer shall state the parts that necessitate requalification upon replacement or repair. Guideline Hospital Waste Decontamination Equipment Page 13/23

13 6 Validation Validation is performed through physical measurements, where necessary complemented or replaced with microbiological tests. Microbiological tests shall always be performed when it is not possible to measure the critical process variables, as well as for decontamination equipment that does not operate with saturated moist heat. Validation is performed to demonstrate that the type and quantity of hospital waste, as specified by the manufacturer, can be effectively and reproducibly processed. 6.1 Type test The manufacturer shall perform a series of tests that take into account the claims on the type and quantity of hospital waste that the decontamination equipment is meant to process to demonstrate that the specified performance is delivered. Where the decontamination equipment is intended to process the full range of hospital waste without the use of a shredder, hollow objects, such as lengths of tube and needles, are presumed to be those that are the most difficult to process. The type test shall clearly demonstrate that these objects can be decontaminated effectively. The tests described in DIN shall be performed for both the disinfection and sterilization cycles. For batch-process decontamination equipment, the procedure described in DIN shall be followed without modification. For continuous process decontamination equipment, it may be necessary to modify parts of the DIN procedure. The manufacturer shall clearly describe the test type procedure and provide a rationale for each deviation from the standard procedure. The type-test procedure and results shall be documented by the manufacturer. This document will also provide the rationale for the selection of the works test. The specifications for the measuring systems used during the type test are described in DIN The requirements for biological indicators that are used in disinfection cycles are specified in DIN and 4. Parts 1 and 3 of NEN-EN-ISO specify the requirements for biological indicators that are used in sterilization cycles. All of the biological indicators shall be used in a process challenge device (PCD). The PCD shall be designed to represent the object or part of an object that is the most difficult to decontaminate that may be present in hospital waste. DIN specifies the acceptance criteria of the thermometric measurements and biological indicator tests in disinfectors. For sterilizers, the measured temperatures shall fulfil the requirements stated in Richtlijnen Steriliseren en Steriliteit; D6103b. Note: When used in decontamination equipment that is provided with a transport screw, stirrer, impellor, etc., it may be necessary to protect biological indicators, PCDs, data loggers, etc., from mechanical impact, for example, by means of steel baskets. This protection must be sufficiently permeable for moist heat in order to ensure the efficacy of the process is not impaired. Guideline Hospital Waste Decontamination Equipment Page 14/23

14 6.2 Works test The manufacturer shall perform a series of tests to demonstrate that the decontamination equipment that is shipped to a purchaser, or parts of the equipment that are assembled on site, meet the specifications. The test program shall at least include the tests that proved to be the most critical in the type test. The test procedure and acceptance criteria are identical to those used in the type test. The manufacturer may decide to perform part of the works test at the user s site during installation qualification. 6.3 Installation qualification (IQ) The purpose of IQ is to verify, at the user s site, the specifications of the process, the equipment, the operation and the generation of moist heat, as well as the quality and quantity of the services needed to run the process. The calibration status of all of the measuring systems for process control, monitoring, and recording, including measuring systems for test purposes, must be established. The manufacturer shall write a protocol for the IQ. 6.4 Operational qualification (OQ) The purpose of OQ is to demonstrate that the decontamination equipment delivers, at the user s site, the decontamination process within the specified tolerances. The test program shall at least include the tests that proved to be the most critical in the type test. The test procedure and acceptance criteria are identical to those used in the type test. 6.5 Performance qualification (PQ) Performance qualification enables the user to demonstrate that the site s hospital waste can be effectively and reproducibly decontaminated. The process variables shall be measured in representative locations in the waste, and where applicable, in wastewater. The measurement procedure and acceptance criteria are identical to those used in the type test. Microbiological tests shall be performed where the continuous measurement of the temperature is not possible during the process or where the efficacy of the process cannot be established by physical means. The test procedure and acceptance criteria are identical to those used in the type test. The following provisions must be taken into account during PQ: The packaging of the waste shall be identical to the packaging that is used in daily routine. The data from at least three consecutive successful decontamination cycles are needed to establish the reproducibility of the process. The hospital waste that is used during PQ shall be quarantined until the results from the PQ establish that the decontamination equipment reproducibly delivers an effective process within the tolerances of the specifications. 6.6 Report The data collected during the qualifications shall be documented and collated in a report. The documents in the report may come from different sources (manufacturer, user, validation service). The report shall at least contain the following information: Description of the decontamination equipment. Description of the processes. Description of the hospital waste. The data established for each process. Evaluation of the data established from measurements and tests, the acceptance criteria and the standards used. The user shall endorse the report by signing it and the decontamination equipment will be released for routine use. Guideline Hospital Waste Decontamination Equipment Page 15/23

15 6.7 Requalification Requalification enables the user to establish that the decontamination equipment continues to deliver the decontamination process within the specified tolerances after maintenance, repairs or modifications have been carried out. The program of tests and measurements may be shorter than the program used for the initial qualification. The user shall draft a requalification program that includes a rationale for the selected tests and measurements. The program shall at least include the tests and measurements that produced the poorest results during the last qualification. Requalification shall be performed: At least once a year. After the replacement during maintenance or repair of parts that have a significant impact on the performance of the decontamination equipment. The manufacturer shall provide the user with a list of parts that require requalification. After modifications to the programmed processes, the packaging of the waste, the amount of waste that is processed per batch or per period, and the type of waste that is offered for decontamination. In general, requalification must be performed after each deviation from the initial intended use. Guideline Hospital Waste Decontamination Equipment Page 16/23

16 7 Routine monitoring and release of processed waste 7.1 Process documentation At the end of each decontamination cycle, the records are verified to establish that the process parameters were within the specified tolerances. All pre-process activities, such as the preconditioning of waste, that are necessary to guarantee the efficacy of the decontamination process, are deemed to be part of the process. The parameters shall be recorded and verified. For continuous decontamination processes, the user shall verify that, during the period that a certain amount of waste was processed, the process parameters at the locations identified by the manufacturer as the most critical were within the specified tolerances, and that the speed of transport through the decontamination equipment was sufficiently low to ensure that the waste was at the decontamination temperature for at least the intended decontamination time. In the event that the processed waste cannot be clearly distinguished from non-processed waste, chemical process indicators must be attached to the packaging of the waste before it is loaded into the decontamination equipment. The use of such indicators is not necessary for decontamination equipment that shreds the waste as part of the process. 7.2 Release of processed waste The process documentation is collated into a release protocol. The user shall verify that the process was within the specified tolerances and will endorse the protocol by signing it. The user will ask the waste disposal service for the details of the information that must be provided with the decontaminated waste. A photocopy of the release protocol and any other requested documents will be handed over to the waste disposal service. Guideline Hospital Waste Decontamination Equipment Page 17/23

17 8 Literature DIN : Desinfektion - Dampf-Desinfektionsapparate - Teil 3: Prüfung auf Wirksamkeit [Disinfection - Steam Disinfection Equipment - Part 3: Efficacy Testing], February 2004 DIN : Desinfektion - Dampf-Desinfektionsapparate - Teil 4: Biologische Indikatoren zur Prüfung auf Wirksamkeit [Disinfection - Steam Disinfection Equipment - Part 4: Biological indicators for efficacy tests], October 2006 D6102: NEN, Steriliseren en Steriliteit, Bowie & Dick test (in Dutch), 1997 D6103b: NEN, Steriliseren en Steriliteit: Valideren van stoomsterilisatoren voor medische hulpmiddelen [Sterilization and Sterility: Validation of steam sterilizers for medical devices], 2006 NEN-EN 285: Sterilization - Steam Sterilizers - Large Sterilizers, 2006 NEN-EN 556-1: Sterilization of Medical Devices - Requirements for Medical Devices to be Designated STERILE - Part 1: Requirements for Terminally Sterilized Medical Devices, 2001 NEN-EN ISO : Sterilization of Health Care Products - Biological Indicators - Part 1: General Requirements, 2006 NEN-EN ISO : Sterilization of Health Care Products - Biological Indicators - Part 3: Biological Indicators for Moist Heat Sterilization Processes, 2006 NEN-EN ISO : Sterilization of Health Care Products - Chemical Indicators - Part 1: General Requirements, 2005 NEN-EN 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, 2001 RIVM Survey 569/05 BMT/TPV/dBr/AvD/cvr, Decontaminatietechnieken specifiek ziekenhuisafval [Decontamination techniques for specific hospital waste], A. W. van Drongelen, A. C. P. de Bruijn and G. W.M. Peters-Volleberg, November 2005, Guideline Hospital Waste Decontamination Equipment Page 18/23

18 Annex 1: Rationale for the decontamination process parameters The key question is whether it is necessary to kill, with a high level of certainty, all micro-organisms in the hospital waste (sterilization) or whether it is sufficient to reduce the number of pathogenic micro-organisms to a level that ensures the safety of the persons handling the waste (disinfection). Sterilization has the advantage of a defined end point; the chance of finding a living micro-organism is less than one in a million. Starting with the high estimated bioburden in hospital waste of micro-organisms per item, a sterilization process per European Pharmacopoeia with twice the standard sterilization time (121 C for 30 minutes), should be sufficient to render the waste sterile. Sterilization in the laboratory destruction autoclaves may prove to be a feasible solution for many hospitals. Due to the limited capacity of such autoclaves, the amount of hospital waste should be limited by strict separation of the waste at the source. Disinfection requires a definition of the infectious micro-organisms that have to be inactivated before the hospital waste can be safely transported to the regional incinerator (AVI). Literature provides lists of microorganisms that are known to be dangerous and should be eliminated before the hospital waste is transported from the premises. The lists contain a large number of viruses. Viruses are not heat resistant and are of no consequence for the choice of the process parameters. Hospital waste containing prions is not dangerous. Prions are dangerous for humans, but according to the current state of knowledge, only if transmission occurs through the eye or the brain. These transmission routes are unlikely to occur while handling waste. In view of their extremely high resistance to sterilization processes, inactivation by incineration is the preferred method. Clostridium botulinum is a dangerous micro-organism that can cause serious illness and is highly resistant to moist heat. Infection from hospital waste is, however, unlikely since the route of transmission is oral [1]. The micro-organisms listed by WIP in its guideline on waste management [2] are also mentioned in categories A, B, and C of the German Robert Koch Institute (RKI) [3]. Bacillus anthracis is, in relation to the decontamination of hospital waste, the most resistant micro-organism. Contrary to sterilization, it is not easy to define an effective disinfection process. The descriptions of the waste decontamination equipment that is listed by RKI indicate that it can take a considerable amount of time for the waste materials to heat up during the decontamination process. RKI points out that users must be aware of the presence of solid masses that are difficult for heat to penetrate, as well as of large containers filled with liquids. In waste decontamination equipment that shreds waste before it is exposed to the actual decontamination stage of the process, a disinfection time of 15 minutes at 100 C is deemed to be sufficient, whereas in general-purpose steam disinfectors, a disinfection time of 30 minutes is recommend to compensate for the poor heat penetration [3]. The process parameters that were first mentioned may be regarded as the reference values to which the waste must effectively be exposed, disregarding the heat-up period. Whether specific waste decontamination equipment delivers an effective process must be established by tests and measurements. RKI uses the German standard DIN [4] for the admission criteria. This standard describes the requirements and methods for the validation of waste decontamination equipment. The methods include microbiological tests in combination with porous materials (textiles, bandages, wound dressings, surgical drapes, etc.) and hollow objects (injection needles, lengths of tubes, etc.), as well as thermometric measurements. The micro-organism used in the tests is Bacillus subtilis, per DIN [5]. This microorganism is present everywhere in the environment and is of no consequence for the decontamination of hospital waste. It is a much used test organism for decontamination processes and is more resistant to moist heat than Bacillus anthracis. Sykes [6] found that, at 100 C, the inactivation time for B. subtilis is a multiple of the inactivation time for B. anthracis. B. subtilis seems to be an acceptable test organism; its high resistance provides an additional safety margin. Due to the large difference in the inactivation time for B. anthracis and B. subtilis, decontamination equipment that is capable of inactivating a challenge of B. subtilis will, with a high level of certainty, be able to inactivate B. anthracis. The risk of micro-organisms growing from the decontaminated waste is negligible. The efficacy of the decontamination process is sufficient to inactivate resistant micro-organisms, diminishing the chance of survivors. Drying the waste during the process further impoverishes the conditions for growth. Guideline Hospital Waste Decontamination Equipment Page 19/23

19 The data on inactivation specified above are only valid for decontamination with saturated moist heat. For dry heat, insufficient data are available from literature to state the process parameters that will produce an efficacy equal to the moist heat disinfection at 100 C for 15 minutes. Sterilization with dry heat is possible using a standard process with a double exposure time, for example, 60 minutes at 180 C. Dry heat decontamination processes are, however, outside the scope of this guideline. Literature: 1. Chin JE, Control of Communicable Diseases Manual, edn 17, vol. pp AMERICAN PUBLIC HEALTH ASSOCIATION, 2000/01, ISDN X 2. Infectiepreventie bij afvalverwijdering vanuit instellingen voor gezondheidszorg [Infection prevention during sanitation for health care facilities], Dutch Working Group Infection Prevention (WIP), June 2004, 3. Liste der vom Robert Koch-Institut geprüften und anerkannten Desinfektionsmittel und verfahren [Robert-Koch-Institute list of tested and approved disinfection agents and methods], Robert Koch- Institut, edn 14, 31 May Desinfektionsmittelliste,templateId=raw,property=publicationFile.pdf/ 4. DIN : Desinfektion - Dampf-Desinfektionsapparate - Teil 3: Prüfung auf Wirksamkeit [Disinfection - Steam Disinfection Equipment - Part 3: Efficacy Testing], February DIN : Desinfektion - Dampf-Desinfektionsapparate - Teil 4: Biologische Indikatoren zur Prüfung auf Wirksamkeit [Disinfection - Steam Disinfection Equipment - Part 4: Biological Indicators for Efficacy Tests], October Sykes G, Disinfection and Sterilization (Spon Ltd., London, 1958), p. 95. Guideline Hospital Waste Decontamination Equipment Page 20/23

20 Annex 2: Correlation between temperature and pressure in saturated steam There is a mathematical correlation between the temperature and the pressure 1 in saturated steam. The temperature and pressure measurements are used in the below equation to determine whether the steam is saturated. In saturated steam, the calculated temperature matches the measured temperature. T = A + B (lnp + C) -1 where: T is the theoretical steam temperature, in Kelvin; P is the measured pressure, in Mega Pascal; A is 42,677 6 K; B is 3 892,70 K; C is 9, Irvine TH. F., Liley, P. E., Steam and Gas tables with computer equations (Academic Press, 1984). Guideline Hospital Waste Decontamination Equipment Page 21/23

21 Annex 3: Validation Schematic representation In order to interpret the validation, it is important to understand the sequence of the type test, works test, installation qualification, operational qualification, performance qualification and requalification, as described in this guideline. Requalification Routine monitoring, change control Specified user requirements Type and amount of waste, monitoring / recording, routine monitoring, validation, etc. Specified function requirements programs, air removal, dryness, air leakage, fault handling, etc. Related to User User / Manufacturer Related to Performance Qualification (PQ ) Validation of actual loads, establish reproducibility Operational Qualification (OQ) Thermometric tests, air-leakage test, dryness test, moist-heat-penetration test. Installation specifications Services, e.g. steam, water, air, drain, power etc., noise, ambience. Design specifications Related to Manufacturer / User Manufacturer Related to Installation Qualification (IQ) Check specifications, drawing, documentation etc. Design Qualification (DQ) Type test / Works test Waste disposal service Additional requirements and conditions Manufacturing Quality assurance of production through certified quality management system Guideline Hospital Waste Decontamination Equipment Page 22/23

22 Annex 4: Persons involved in drawing up the guideline This document was drafted by: Mr A. de Bruijn (National Institute for Public Health and the Environment: Medical Technology Section) Mr A. van Drongelen (National Institute for Public Health and the Environment: Medical Technology Section). The following persons are acknowledged for their valuable input during the drafting process: Mr G. Bakker (Darwin Business Partners) Ms Th. Daha (Dutch Working Group Infection Prevention, WIP) Mr J. van Doornmalen (Bureau Veritas) Mr J. van Hasselt (Van Gansewinkel) Mr R. Heijlijgers (Bureau Veritas) Mr L. Lamphen (University Medical Centre Utrecht) Mr L. Maas (University Hospital Maastricht) Mr P. Maris (Sanamij) Mr T. Ritmeijer (Van Vliet Medical Supplies) Ms A. Teuns (Van Gansewinkel) Mr G. van Vliet (Van Vliet Medical Supplies) Mr C. Wagenaar (Nido Recycling Techniek) Mr E. Wigmore (Nido Recycling Techniek). Mr R. van Zwieten (Ministry of Housing, Spatial Planning and the Environment) Full consensus on all of the requirements described in this document was not achieved. When asked, the contributors may express an opinion different from the information in this document. This document is a translation of the Dutch guideline Richtlijn decontaminatie-apparatuur ziekenhuisafval, dated December Guideline Hospital Waste Decontamination Equipment Page 23/23