This article was featured in ‘Building Services News’ magazine. Written by Fergus Dunphy of PM Group, the article evaluates the use of fan filter unit HVAC systems for pharmaceutical Fill Finish facilities.
A fan filter unit is exactly as described, a fan mounted on a filter. The use of fan filters first emerged in the electronics industry where there is a requirement for higher classification cleanrooms in water fabrication plants. They were then introduced into the pharmaceutical industry where they were modified for ease of cleaning and disinfection.
The idea is that the fan filters draw air from the ceiling space above the unit and push the air through the HEPA filter into the cleanroom below. The number of fan filter units installed into a ceiling grid will determine the air volume supplied to the room. The article discusses both the advantages and disadvantages associated with fan filter units. Such advantages include a reduction in the size of distribution ductwork required, a reduction in the overall building footprint and an area above the cleanroom which is much easier to maintain than plantroom spaces congested with ducting. Dunphy lists some disadvantages as the lack of understanding of fan filters in comparison to ducting systems, and the lack of installation contracts and equipment suppliers available for fan filter systems….
Download a printable PDF version of the article (2.6MB file)