Monday, February 22, 2010

Clean room testing and containment laboratories

I have been working in containment consultancy for few years and I still can't stop amazed by the confusion in the market between clean room and containment laboratories. Plenty times I have come across news and laboratories which are tested by clean room standards. Many times, the firms doing work in containment laboratories have been certified for clean room work, get the work in the laboratories for having such certification and well, deal with the laboratories as if they are clean room.

As a start, clean room is to keep things from going in, although generally there are some that also keep things going out. However, the first and foremost key issue is to keep things from going in. On the other hand, containment laboratories (BSL3/4) are intended to keep things from going out. Although there are some BSL3 that also provide means to keep their facilities clean either with the intention to improve work quality or simply to improve indoor air quality (arguably unnecessarily at times). Hence, the key principles between clean room and containment laboratories are rather different (or opposite, if you like). Therefore, one has to be careful in choosing contractors to ensure that safety and not quality is the focus of the work in containment laboratories.

Unfortunately, clean room is heavily regulated with plenty of standards while containment labroatories are something new without many technical standards guiding it. For a start, the website of NEBB, a popular accreditation body that provide certification to firms doing work in clean room, does not list Biosafety Cabinet (BSC) in their testing list. BSC is in fact, arguably the most important equipment in a containment laboratory, providing protection to the personnel, product and environment. I have seen places where only the HEPA in the BSC and the BSC is called as "certified" although popular BSC standards such as NSF 49, JIS K 3800 or EN 12469 call for other tests such as downflow and face velocity, smoke test, etc. for the cabinet, both in factory and on site! There is also a separate BSC certification scheme organized by NSF which an owner of BSC has to take note of. Therefore, BSC is not simply the HEPA filters installed. The airflow performance has to be tested as well. This is a second issue which many firms dealing with clean room are not familiar with.

The third issue is with the HEPA certification. Clean room has plenty requirements for HEPA and such facility puts a lot of scrutiny to the HEPA, which is good and similar to containment laboratories. However, sometimes, some clean room requirement would allow particle testing using atmospheric air. Owners of a containment laboratory should take note that such testing is not something acceptable for a containment laboratory! Acceptable HEPA leak testing in containment laboratories include DOP / PAO testing, scan tested or by overall penetration. Owner has to be clear as well that the testing is to establish a leak level and appropriate testing standards and methodologies acceptable to containment laboratories have to be specified by the testing firm. Unfortunately, technical standards for HEPA in containment laboratories do not exist. Many biosafety guidelines would refer to acceptable leak level but now how they are to be tested. Canadian guidelines goes one step further and require adherence to IEST standard which is essentially a clean room standard. However, the guideline is clear about the type of testing required and I can vouch that atmospheric testing is not something commonly accepted for containment laboratories.

Last difference is on the sampling of indoor air. Sampling of bacteria in the air is not something commonly practiced in containment laboratories. Gaseous decontamination of containment laboratories also uses biological indicator to validate. The biological indicators are mostly in the form of spore strip or other proprietary products. However, clean room at times uses bacterial sampler. Again, this is a different practice.

In conclusion, clean room testing standard is not directly applicable to containment laboratories and owners of a laboratory should question which standard they would want to comply with. Some testing commonly accepted in a clean room facility may not be acceptable in a containment laboratory setting.