Medical Device manufacturers are required to establish documented requirements for cleanliness of product under varying circumstances, see paragraph 7.5.1.2.1 of ISO 13485:2003.
Typically product cleanliness is assured through the selection of and controls applied to suppliers in conjunction with product manufacture within a cleanroom environment.
Both notations are widely used, and providing the words are used properly in context the correct version is largely irrelevant. For the purists ‘cleanroom’ is the correct notation. A clean room is a room that is clean, whereas a cleanroom is a room that has a controlled environment in terms of one or more of the following: particles, fibres, microorganisms, temperature, humidity, lighting, activities and personnel. Of all these parameters, the most significant is particulate. Measures of particulate contamination would normally include inert particle, bacterial, fungal and small fibre contamination.
Cleanroom classification by air cleanliness is given by the international standard ISO 14644-1:1999. This classifies air cleanliness from the most clean Class 1 through to Class 9. Cleanrooms are frequently referred to as Class 10,000 or Class 100,000 or sometimes Class J or Class K etc. These latter classifications arise from the former (and now withdrawn) standards Federal Standard 209E and BS 5295:1989.
ISO Class 8 is analogous to Class 100,000 and Class K
ISO Class 7 is analogous to Class 10,000 and Class J
It is important to note that while the standards are comparable they are not identical.
There are different levels of cleanrooms i.e. some have more particles than others. Cleanrooms are classified according to the maximum number of particles of different sizes per cubic meter of air allowable in the cleanroom. The (now withdrawn) Fed Std 209E used cubic feet as their measure so a class 100,000 cleanroom contained no more than 100,000 particles of 0.5μm or larger per cubic foot of air. ISO 14644-1:1999 uses metric units so the equivalent of a Class 100,000 cleanroom under ISO 14644 would have no more than 3,520,000 particles of 0.5μm or larger per cubic metre of air – a class 8 cleanroom. ISO 14644 introduced 9 classes of cleanrooms each with a maximum number of particles of 0.5μm or larger per cubic metre of air. What’s so important about 0.5μm? Just about everyone uses 0.5 and 5.0 as a reference point. Laser particle counters are used to measure airborne particulate contamination and typically report 0.3μm, 0.5μm, 1.0μm, 3.0μm, 5.0μm and 10.0μm particle sizes.
At High Edge Consulting we have seen the good, the very good and the bad when it comes to cleanrooms. Our consultants have direct experience of working in cleanrooms and know what works and more importantly what does not work when it comes to layouts. When you are planning and designing cleanroom layouts the practicalities must be considered . We can help you plan and create a specification for your cleanroom, including equipment lay outs, over pressure cascade, return grille locations and so on. We can offer practical advice and make suggestions based on solutions to suit your financial commitment.
How clean is your cleanroom? At High Edge Consulting we have considerable experience in helping manufacturers to minimise their Cleanroom contamination. If you have cleanroom concerns we can troubleshoot your cleanroom for you. We can give you an impartial view of your cleanroom by examining the layout, working practices, operator behaviour, cleaning materials, cleaning regimes, entry and exit procedures, clothing requirements and Cleanroom location in relation to other aspects of your facility. We can advise you regarding your cleaning materials, frequencies and practices that are necessary to reduce the contamination that does occur within your cleanroom. Any recommendations would balance the risk to contamination against the costs involved in providing the solutions, as appropriate to your needs. We can advice you on tests to demonstrate that your product is in particulate and microbial controlled.
You may not have the resources or business need to employ a full time Microbiologist. High Edge Consulting can provide you with a consultant Microbiologist who is professionally qualified. They can explain tests that are required to you, set warning and action limits for each test. If you have no historical test history we can still approve your test results based on our experience and professional judgement until you have developed enough history to allow us to set your limits. Our consultant can liaise directly with the test laboratory and receive test reports (or copies) direct and review each test result as it becomes available. Our Qualified Microbiologist can sign off each report on your behalf as acceptable or not acceptable, and in the case of the latter can recommend immediate and relevant corrective action that you need to take to minimise any down time. We can also trend your results for you and send you monthly updates showing trends in your testing. This can be an invaluable aid in pre-warning of impending problems – Prevention is better than cure.
