IEST RP-CC001.7

This Recommended Practice (RP) covers basic provisions for HEPA (high-efficiency particulate air) and ULPA (ultra-low penetration air) filter units as a basis for agreement between customers and suppliers. This RP describes 11 levels of filter performance, or types, and six grades of filter construction. For the types and grades that require scanning, these filter types generally apply to rectangular filters. Semi-circular, cylindrical, V-bank filters, and other construction configurations may not be readily scanned and thus will not meet the requirements of the filter types requiring scanning.