The Performance Evaluation of Re-Circulating. Air LEV Systems

Transcription

1 The Performance Evaluation of Re-Circulating Air LEV Systems Monday 24 th February 2014 Held at: Flextraction Ltd 10 Digby Drive Melton Mowbray Leicestershire LE13 1UT Speakers: Walter Gilder (WPG Paul Ramsden (PR) Welcome Notes Wally Gilder (WPG) opened the meeting welcoming all and thanking them for their attendance, pointing out that those attending represented a very good spread with some of the major players in the LEV industry in attendance, along with representation from the HSE. He went on to cover general housekeeping and safety issues and explained the format of the meeting, before handing over to Paul Ramsden (PR). Opening and Outline PR gave a brief overview of his position as an Occupational Hygienist and informed all that ILEVE who, under the auspices of CIBSE, was seeking to raise the awareness of the performance evaluation of re-circulating air LEV systems. The belief was that the subject under discussion was important enough to be tackled by ILEVE and that upon completion, any final paper would go out to all ILEVE / CIBSE members; somewhere in the region of 20,000. It was felt that the day s meeting should take the form of a discussion group, offering all attendees the opportunity to voice their opinions and beliefs on the subject. This would then enable all matters raised to be considered, taken forward and after further consultation, addressed by a sub-committee of ILEVE before a structured document could be adopted. He explained that a lack of standard had been identified with respect to the performance evaluation of re-circulating air LEV systems and that as far as he could ascertain, historically, this issue had failed to be addressed by any regulatory body. It was accepted that the Control of Substances Hazardous to Health (CoSHH) Regulation 9 stated that there was a duty of care and that in tandem, the Approved Code of Practice (ACoP), a quasi legal entity, required compliance with the ACoP or better.

2 By means of several slides PR gave an illustration of some the re-circulatory systems that are currently in use, from shaker units, re-circulatory cabinets, through to soldering units and large range systems. PR explained that prior to the meeting he had sought a response through a questionnaire he submitted to the ILEVE members. Disappointingly, but perhaps not surprisingly, and despite the simplicity of the questionnaire, the response level was less than anticipated, somewhere in the region of 12 forms being returned completed. There were 4 questions: 1 The first question asked if anyone was aware of standards for testing of recirculatory units none were identified. It was pointed out by one of the attendees that there was a European Standard that existed although it did have limitations. 2 The second question asked for indication of existing procedures in members workplaces on the whole this was ignored, although it was pointed out that some members currently use Direct Reading Instrumentation. 3 The third question sought opinion on how testing should be carried out no opinions were forthcoming. There was some discussion between PR and the floor, questioning whether it should be all re-circulatory systems that should be checked. It was highlighted that as there was a wide range of different types of systems, should any future guidelines be aimed at a general procedure or should it be more specific, detailing the procedures for each given system. In principle, it was agreed that in the first instance, some wide ranging guidelines would be easier to adopt and be considered progress against the lack of guidance that is available at present. The question was also raised as to whether ATEX systems should be included, and again it was felt that whilst they should, maybe this should be addressed at a later stage. PR made it clear that all comments would be open for discussion and consideration. 4 The final question asked members how they thought the issuing of formal guidelines would be received by companies, organisations or clients whilst some thought they would be received with a degree of scepticism, others thought that in general they would be positively received. In summing up the opening part of the presentation, PR reiterated that ILEVE would need to consider either general or specific guidance and if specific, that would bring with it its own problems; there would always be anomalous issues guidance aimed at a specific substance being used may not be relevant when the source substance is changed to something either more or less harmful. There could also be issues over competency and training; however, the bottom line must be that whatever is produced by ILEVE has to be achievable.

3 From the floor it was asked if energy saving was a primary factor in considering re-circulatory systems. Whilst a consideration, it was felt that there were a number of other factors that would influence the selection of a re-circulatory system, including the flexibility required by a movable process or the lack of need to install ducting, resulting in a saving and/or convenience. The floor also raised the issue over the potential rights and wrongs of extraction to atmosphere and the costs that could be attracted by such an action, through the need to obtain a licence. PR thought that this was an issue of perception, as in reality it could be less of a problem. It was also pointed out from the floor that it was not uncommon for LEV to be an afterthought, resulting in the option of re-circulation be adopted. In continuing, PR pointed out that there were a number of questions that should be raised for discussion. 1 When is re-circulation acceptable? Whilst pointed out that re-circulation was banned in some countries, it was felt by the floor that this was not an option that ILEVE should advocate, however, it could be that there could be some substances that perhaps should not be re-circulated. There was discussion on the issue of toxicity and that in the formulation of any guidelines, it may be advantageous for ILEVE to implement a framework based around the Hazard Band Rating System that is utilised by the HSE; the categorisation of risk on a scale of A through to E, where A could result in an irritation, with exposure to those in category E causing cancer. The floor reiterated that the demands of European Standards for wood dust required constant monitoring and alarming. It was considered that when a single exposure could result in significant harm then perhaps recirculation was the wrong option. There was discussion on the potential problems associated with the production of guidelines that imposed an increase in standards cost / impact on manufacturing / choice available / differentiation (LEV v Vacuums) / on tool systems. When put to the floor that guidance should be based around the toxicity levels, there was no disagreement. There were some questions over whether ILEVE members should be issuing advice or supplying information. It was considered that advice on the purchase of equipment is based on the information available and the application being carried out. Commissioning of equipment being used as per specifications at the outset would confirm correct functionality. It was highlighted that testing should include all processes as outlined at the selection stage. The floor raised the issue of better labelling of equipment at the point of use, detailing what can and cannot be extracted this is in addition to the inclusion of such information within the commissioning and testing reports. The HSE representative raised the point that the more specific guidelines were, the more difficult they would be to produce and ensure adherence. It would be more beneficial to start out general and then evolve into something more details as progress is made.

4 PR requested a show of hands as to ILEVE progressing with the production of advice and that it should be based around toxicity levels this was agreed. It was considered that ideally a table indicating the suitability of filters, incorporating mixed uses, would be well received, however, it was considered that it could be problem laden. The thought was that something along the lines of the coding currently utilised for fire extinguishers would be advantageous. As a minimum, better labelling over use and replacement would be a task that could be championed by ILEVE. There was discussion over the merits of particle filters versus carbon filters, the later not being perceived as suitable for re-circulatory processes. As with other matters raised, it was considered that the correct balance had to be achieved over being a useful source of information without containing too much information - a balance would have to be achieved. 2 Effectiveness what are we verifying? PR put forward some of the issues around effectiveness and what are considered appropriate levels as indicated in the ACoP, indicating that this was a tricky question. The principle issue in question being the lack of definition as to how far below the WEL is acceptable and should the same level be acceptable for all degrees of toxicity? PR was aware of a European Standard for on tool extraction with regards to the use of filters but not a level of extraction that should be obtained. There was discussion from the floor and it appeared that the majority of those voicing an opinion, were working towards a target of <10% of the WEL or <5% on returned air. However, there was no source stating that this is acceptable or correct. The question as to whether this should this be the same target level if the source is a nuisance or potentially carcinogenic was put out. More discussion took place with the general consensus being that best practice would be to achieve as far below the WEL as was practicable. PR went on to highlight some of the deficiencies of Occupational Exposure Limits (OELs). It was considered by those present that for material of all toxicity the level should be no more than 10% of the WEL or other OEL. Other influencing and potentially detrimental factors, such as background levels, exposure times and multiple systems within an environment, were also discussed. PR sought confirmation from those present that ILEVE should be producing guidance indicating that the above figures should be those to which all members should be working agreed. He further requested that the ILEVE working group should be using those figures when more stringent requirements are not available agreed. A number of factors around how assessment can be practically achieved were discussed; including pointing out that testing under laboratory conditions is something that cannot be clearly correlated to testing in a working environment. The use of qualitative and quantitative methods was also raised, with a number of points being questioned as to what should be checked, what hazard system should be used, the benefits and disadvantages of using direct reading instruments.

5 It was pointed out that we should be not only pointing out the benefits of testing but also its limitations and utilise this as an aide to increasing the testing standard. It was highlighted from the floor that there has been a noticeable change in attitude with some customers being much more accepting of and understanding the need for testing. PR questioned the functionality of systems with integral emission monitoring, asking what was actually being monitored, how are they maintained and serviced, their calibration and what are the demands that make them reliable? It was considered that this type of system is often ignored and some expansion should be included within the ILEVE guidance. Clarification should be give for testers, qualitative and quantitative testing being preferred with more detailed requirements being made when retesting is required. With regards to testing problems, it was envisaged that all should be considered and as far as possible, be addressed. PR raised the belief that during examination testers should attempt to verify returned air quality and in the event that this was not possible, the duty holder must be informed. The matter of what recommendations should be in place for integral systems in respect of maintenance, servicing and calibration, was raised. It was also voiced that manufacturers should be recommended to design systems with suitable test points, specifically with regards to re-circulated air. PR summed up the presentation by stating that in the first instance, and as a means of progressing the issue, it would be advantageous to submit a list of all points for consideration to all concerned by . This would afford recipients the opportunity to comment on any topic that they considered they either had a level of expertise or a sound opinion, and in turn, these would be collated and then reviewed by a working group from ILEVE. In due course and before any finalisation was made, all attendees would be invited back to be given the chance to hear first hand, the findings and recommendations of the working group. After that stage the results could be sent out to all for final comments. This was accepted as the way forward. WPG thanked all for attending and the meeting closed at 14:25. J Cunningham Recorder