Historical
DIN EN 1822-4:2001
High efficiency particulate air filters (HEPA and ULPA) - Part 4: Determining leakage of filter elements (Scan method); English version of DIN EN 1822-4 (Foreign Standard)
The document describes a procedure for testing filter elements for local penetration values which exeed permissible levels (leak) using the particle counting technique. For this purpose a probe is moved in touching or overlapping tracks without gaps close to the downstream side of the filter element which is loaded with a test aerosol. A sample volume flow rate is led from the probe to a particle counter. The local penetration (leak) is resulting from the ratio of the downstream to the upstream particle counting.
CONTENT PROVIDER
Deutsches Institut für Normung [din]
Deutsches Institut für Normung [din]