Department of Defense Military (MIL) Specifications
MIL-F-51079 - Filter, Medium, Fire Resistant, High Efficiency
National Consensus Standards
American Society of Mechanical Engineers (ASME)
ASME AG-1 Code, section FC - HEPA Filters
ASME 510-1980 - Testing of Nuclear Air-Cleaning Systems
Institute of Environmental Sciences, Mt. Prospect, Illinois
IES-RP-CC-001.3 - Recommended Practices for HEPA Filters
UL 586 - Standard for High Efficiency, Particulate, Air Filter Units
Inspection and testing of a nuclear grade filter to verify certain characteristics or
properties which determine acceptance or rejection of that filter.
An index of the energy required to maintain airflow through a filter. Airflow resistance
is measured in terms of the air pressure difference (pressure drop) across a filter at a
specified flow rate (e.g. see section 5.2.2, Table-1, Standard DOE-STD-3020-97).
Note: The initial airflow resistance of a new filter serves as an index of the filter's
potential loading capacity.
Count Geometric Mean Diameter (dg)
ln dg = 3 ni ln di
where ni = the number of particles in the ith size category,
di = diameter of particles in the ith size category, and
N = 3 ni = the total number of particles.