Toolkit for safe Use of Microbiological Safety Cabinets(MSC s) What Do I Need To Do? How Do I Manage the Use of MSC s Recommendations 1
What Do I Need To Do Head of Department? Information, induction, supervision and training Check if your department has addressed the health and safety management arrangements by providing suitable information and training about the risks of working with biological agents including the safe use of MSC s If so, appoint a member of your department to co-ordinate the training and record keeping requirements of MSC s with Estates Services and explain their roles and responsibilities. Liaison with Estates Services Check if your department has addressed the health and safety management arrangements relating to the safe use of MSC s by incorporating this local rule If so, appoint a member of your department to co-ordinate the design,maintenance and requirements of new and existing MSC s with Estates Services reerequirements of all MSC;s within the department CoSHH Risk Assessments Check there is a process for identifying, recording and reviewing CoSHH risk assessments involving the use of MSC s. Receive regular updates from the CoSHH risk assessor on progress with the CoSHH assessment programme. Purchasing Policy Instruct appointed person to liaise with MSC users on all requirements of new equipment Instruct appointed person to only purchase MSC s according to the Hazard Group identified and from a reputable supplier in consultation with Estates Services and Safety Services Measuring Performance Measure performance regarding the safe use of MSC s e.g. feedback from CoSHH risk assessments; feedback from annual maintenance programme; ensure training records are updated and completed Review the minutes from consultation meetings with Estates Services. Reviewing Performance Review the performance of MSC s and incorporate any areas of improvement into the objectives in the Departmental Annual Safety Report. 2
What Do I Need To Do MSC co-ordinator/dsc? Information, Instruction and Training Provide all users with relevant training on safe mode of operation and function of all controls and indicators. Provide all users with relevant training on safe working in MSC s, the principles of airflow and the appropriate and inappropriate use of MSC s Provide all users on decontamination methods after use Document and maintain training records. Maintenance of MSC s Maintain an up to date list of MSC s and their location within the Department Ensure annual maintenance programme is adhered to Ensure MSC s are effectively disinfected prior to maintenance Ensure pre-filters are regularly checked and replaced as necessary Ensure H.E.P.A. filters are checked as part of the annual maintenance Carry out face velocity testing regularly to monitor the air flow, operator protection and containment level of the cabinet Communicate Liaise with Estates Services, regarding design and siting of any new MSC s Liaise with Estates Services, regarding commissioning of all new or re-sited MSC s Liaise with Estates Services, regarding the annual maintenance programme Communicate the timetable and results of all maintenance issues to managers and affected staff/students. Regularly update the Head of Department on all aspects of MSC maintenance 3
How Do I Manage Safe Use of MSC s - Head of Department? Appoint a MSC co-ordinator Select a member of staff who is able to understand the risks associated with working with microbiological safety cabinets; Explain their role and duties Spend time collating information to assist in identification of MSC issues Co-ordinate implementation of recommendations including training Monitoring Progress Explain to the MSC co-ordinator how often you want to be updated on progress and by what route. Depending upon the size of the department and number of MSC s,the time scale will vary but it should be sufficiently frequent to enable any significant issues to be communicated at an early stage thus enabling remedial action to be taken promptly. Planning At the start of each year objectives relating to microbiological safety cabinets must be considered. For instance - what are the risk assessment and training programmes, what reviews or refreshers to be planned in. What new equipment will be purchased and if it has been adequately researched as to its fit for purpose. Communication Use department newsletters, staff meetings etc. to keep staff apprised of how MSC issues are being managed. This could include any timetable of annual maintenance, significant findings from maintenance, updates to location and usage. Measuring and Reviewing Performance Use the annual maintenance reports to evaluate the performance of all MSC s within the department. Implement a replacement programme based on maintenance report if necessary. 4
Recommendations for Safe Use of an MSC For Fumigation How D Prior to Use Before starting the work or placing any biological material in the cabinet the following tasks should be performed: Put on the appropriate protective clothing according to the level of containment and the risk assessment for the work; Remove the night door (Class I and II); Ensure that the cabinet is switched on and running for sufficient time to allow air- flow stability before starting the work; Do not use unless the airflow indicator is registering in the 'safe' zone; Prepare thoroughly for the work, e.g., number or tubes, flasks, dishes etc., organise media, solutions, etc. (a check list may be useful, and/or referral to protocols, codes); Ensure active solutions of appropriate disinfectants (and granules or powders as required) are available according to local codes and in the proper container; Ensure the inside of the cabinet is clean and free of clutter. It is commonly good practice, prior to commencing work, to clean the outer window with 70% Ethanol, then cleaning the interior of the window and the surface of the MSC; Ensure the laboratory door is closed; Ensure any equipment required for the work is available and ready for use, However, care must be taken in the selection of equipment in order to minimise the disruption to the air flow. Place work items in the cabinet, ensuring clean and dirty materials are kept separate. During Use Whilst working at the cabinet the following safety precautions should be taken: Do not overcrowd the cabinet. For open-fronted cabinets, always work as near to the centre of the work area as possible, but at least 15 cm from its front. For Class II cabinets, never obstruct the air in-flow grille or any exhaust grilles. Obstructions will adversely affect performance, in particular operator protection. Large equipment (e.g. centrifuges, especially air-cooled models) should not be used within an open fronted cabinet unless appropriate testing has been done to establish that containment performance is maintained. Do not mix sterile with infected materials and avoid passing potentially infected material over clean material. Dispose of equipment and contaminated material appropriately after use. Wherever practicable at containment level 2, this means disposal into appropriate and approved containers or disinfectants within the safety cabinet. Do not allow entry to any casual visitors whilst working at the MSC. All other authorised users of the facility should be discouraged from making movements that may affect the performance of the cabinet. Never use a cabinet if its operational safety is in doubt. If the alarm sounds, make the work secure, for open-fronted cabinets place the front on the cabinet, and inform the appropriate people according to local arrangements. Do not rely upon a safety cabinet to cover up for poor work. A GOOD CABINET CAN NEVER BE A SUBSTITUTE FOR GOOD PRACTICE OR GOOD MICROBIOLOGICAL 5 TECHNIQUE.
Recommendations for Safe Use of an MSC For Fumigation After Use After completion of the work the following actions are required: Check the performance of the cabinet. Remove samples for incubation, etc., after wiping down flasks, containers, etc. as appropriate with disinfectant. Ensure that all containers for autoclaving and incineration are labelled correctly and secured. Only remove contaminated materials from the cabinet as directed by local protocols. Normally this will mean only when the material can be taken directly to the autoclave unless local holding bins lined with autoclave bags are available. Wipe all surfaces with disinfectant and discard tissues into an autoclavable waste bag - do not place into the normal waste stream. Let fan(s) run for at least 5 to 10 minutes before next user. 6
Requirements for Safe Fumigation For Fumigation Prior to commencing any form of fumigation, notice should be served to all personnel either working in the laboratory or in its vicinity. Restricted access should be enforced by means of appropriate safety notices informing personnel of the hazard. Security should also be informed The fumigant should be generated with the night door securely sealed and the non-return valve left closed. Passive migration of the fumigant through the filter can occur but the valve could be left open and the fan running for 10-15 seconds to ensure penetration of the filter medium. The valve should then be closed and the fan switched off while the remainder of the fumigant is left to disperse within the cabinet. After at least six hours, or preferably overnight, the fumigant should be exhausted to atmosphere by switching on the fan and allowing air from the room to enter the cabinet. Before venting the formaldehyde in this way, it is essential to ensure that no-one is in the vicinity of the exhaust outlet and that the exhaust air cannot enter nearby windows or ventilation air intakes. (see suggested protocol below) If the MSC exhaust is connected to the building extract system, the safety cabinet exhaust damper should be closed to prevent fumigant being dragged from the cabinet by the extract. In this case, the building extract should not be connected to the buildings air circulation system or the fumigant will require to be exhausted by another means. If filters are to be changed after fumigation, the discarded filter unit should be bagged and incinerated - please contact the Estates Services for guidance on filter disposal. Note: Legislation requires that both pre and high efficiency particulate air (HEPA) filters used against agents of category 2 status or above must be made safe before disposal. Before fumigation of cabinets with formaldehyde, all vessels containing hydrochloric acid and chlorinated disinfectants should be removed to prevent the possibility of forming bis (chloromethyl) ether which may be carcinogenic. Formaldehyde is a Schedule 1 chemical under CoSHH Regulations and has a WEL (workplace exposure limit) of 2ppm or 2.5mg m 3. Exposure to fumes can cause intense eye and respiratory tract irritation and repeated exposures have led to allergic responses of the respiratory tract and the skin. The agent has been linked to carcinogenicity in animals and possibly in humans. Leakage of formaldehyde and its vapour into the laboratory can be controlled by use of relevant covers and taping over temporary openings (e.g. around the front aperture). Formaldehyde levels can be measured using a sampler and detector tubes available commercially (e.g. Draeger) - any hint of formaldehyde by smell will almost certainly indicate the presence of an unacceptable concentration of the fumigant. 7
Suggested Protocol for Fumigation It is recommended that this procedure is carried out over the weekend, if possible, to allow for minimal disruption to normal work in the laboratory. It also allows a sufficient time elapse to ensure clearance of all formaldehyde gas. Inform all personnel working in the laboratory and adjacent vicinities that fumigation is being performed on the MSCs; Attach approved NO ENTRY signs to all access doors leading into the laboratory and inform Security (JA3333) that this procedure is taking place. Switch off the cabinet fans; If the cabinet is a recirculation type, fit the fumigation adaptor kit to the discharge and position the other end to vent to safe atmosphere; Close the manual shut-off damper; Fill the vapouriser with the correct amount of formaldehyde and water to produce the amount of formalin vapour required. (Consult BSEN 12469:2000 for guidance) and screw on the aluminum cap - finger tight, having checked the gasket in the cap is undamaged; Place the vapouriser in the cabinet ensuring nozzle is pointing inwards toward the back panel of the MSC; Fit the closure panel/night door and fully seal the front screen and closure panel with sealing duct tape to ensure there are no leaks; Post a notice on the front of the cabinet and external lab doors indicating that fumigation is in progress; Switch the vapouriser on; After approximately 10 minutes, switch the cabinet fans on for 10-15 seconds to ensure fumigant is taken into the filters. Never allow fans to run any longer than this with the front cover secured as this will damage the motor mechanism of the MSC. Perform this twice; Leave the cabinet in this condition overnight, but if not possible at least for a minimum of 6 hours; If the cabinet is a recirculation type check the exhaust of the fumigation adaptor kit is in a position to discharge safely and open the manual shut-off damper; On entering the lab the next day, a respirator fitted with a formaldehyde filter should be worn until safe levels of formaldehyde gas has been established. This can be done quickly and easily using a formaldehyde-meter or detection sticks e.g., Draeger; Prior to venting the formaldehyde, check no-one is in the vicinity of the exhaust outlet and that gas will not enter any open windows nearby; Exhaust the formaldehyde from the cabinet by switching on the fans and opening the closure panel/night door slightly (remove bung if fitted, or crack open) until the majority of the formaldehyde has been exhausted; After about 10 minutes the night door may be removed completely; Any poly-formaldehyde residue in the vapouriser may be removed by rinsing with water containing 1% mild detergent; Any poly-formaldehyde residue left on the surface of the MSC can be neutralised by swabbing with a 2% ammonia solution; and Run the cabinet for at least a further 15-20 minutes to remove the last traces of formaldehyde before removing respirator - always check the formaldehyde levels with either a formaldehydemeter or appropriate Draeger stick. If the cabinet is being serviced by engineers, allow the cabinets to run a minimum of 24 hrs before allowing access to the MSC. If the cabinet is a recirculation type, the fumigation adaptor kit must be removed before the cabinet is used again. 8
Recommended Standards for Siting of MSC s For Fumigation Siting microbiological safety cabinets to limit disturbance 9
Recommended Standards for Siting of MSC s Handy Hints for Siting of MSC s For Fumigation Handy Hints for Siting of M Siting microbiological safety cabinets to limit disturbance-continued 10