Airfow ResistanceAn 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 of DOE Standard
DOE-STD-3020-97). Note: The initial airflow resistance of a new filter serves as an
index of the filter' potential loading capacity.
Approved Test AerosolParticle-generating materials approved by DOE for test
activities at a DOE HEPA Filter Test Facility (FTF). Test aerosols currently approved by
the DOE for tests conducted in a DOE FTF are di-octyl phthalate (DOP), also known as
DEHP, and di-octyl sebacate (DOS), also known as DEHS.
Filter Test Facility (FTF)A facility accepted by the DOE specifically to conduct quality
assurance tests of HEPA filters.
High Efficiency Particulate Air (HEPA) FilterA throwaway, extended-media, dry type
filter with a rigid casing enclosing the full depth of the pleats. The filter shall exhibit a
minimum efficiency of 99.97% when tested at an aerosol diameter of 0.3 micrometers
aerodynamic diameter. The maximum airflow resistance shall be as specified in
Section 5.2, Table 1 of DOE Standard DOE-STD-3020-97.
Nuclear FacilityNuclear facility means reactor and nonreactor nuclear facilities. This
definition is taken from 10 CFR 830- Nuclear Safety Management, section 830.3,
Definitions. "Nonreactor nuclear facility" as well as "reactor" are defined in detail in this
section of the Code of Federal Regulations.
PenetrationThe downstream test aerosol concentration, expressed as a percentage
of the upstream test aerosol concentration.
Preparing ActivityThe DOE organization responsible for issuance and interpretation
of this standard.
This standard is applicable to all HEPA filters defined as performance Type B filters in
the Institute of Environmental Sciences publication "HEPA and ULPA Filters,"IES-RP-