scope:

This Recommended Practice (RP) covers definitions, equipment, and procedures for leak testing high-efficiency particulate air (HEPA) filters and ultralow-penetration air (ULPA) filters in the factory they are produced, at the job site before they are installed, and after they are installed in cleanrooms and in unidirectional-flow, clean-air devices. When used in conjunction with other RPs, including IEST-RP-CC001, IEST-RP-CC002, IEST-RP-CC006, IEST-RP-CC007, IEST-RP-CC021, IEST-RP-CC028, and IEST-RP-CC036, this RP may be used to define the basis of an agreement between the customer and supplier in the specification and procurement of HEPA and ULPA filters, and in the testing of these filters in unidirectional-flow, clean-air devices and cleanrooms. This RP also includes procedures for measuring the uniformity of the aerosol challenge approaching the filter under test.

Although the scanning methods in the factory and in situ (in the field) appear similar, they are not identical, mainly due to increased variability for in situ testing. In this revision of the RP, the recommended procedures for factory and in situ testing are separated for ease of use. In factory and in situ testing, if a leak is detected while scanning a filter, it is recommended that the magnitude of the leak be quantified with the scanning probe stationary over the detected leak.