Air Filtration Design and Selection Based on Outdoor Air Quality and Type of Area Served
Basics of Clean Room Design Considerations
Clean rooms today are high technology solutions with high or very high demands on the air cleanliness level. Not only particulate matter but also airborne molecular contaminants (AMC) are addressed in more and more applications. Therefore, it is important to estimate the level of air cleanliness in the cases of new production of, or reconstruction of a clean room.
The air cleanliness level in a clean room is dependent on the quality of the supply air, contamination sources and the design of the ventilation system. The heart of the clean room consists of the filters which can be selected in different qualities in different locations in the clean room.
Today a clean room should be classified according to ISO standards or similar applicable standards. The cleanliness level is often described as a certain accumulative concentration of a specified particle size. Typically, 0.1, 0.3 and 0.5 μm is used. The latest ISO DIS 14644 is given below.
Air filters play a very important role in clean room environments with demands on high cleanliness. HEPA filter-H14 according to EN 1822 is the recommended filter grade for use in pharmaceutical cleanrooms. ISO have recently published a new standard 24963, the equivalent to H14 would be ISO 45E, IEST grade would be type K.
EN 1822 Test standard
(All above information & Data are derived from Book records of Filtration Standards & Other related standards, research papers and its related webpages)