PERMEANCE, AIR

The rate at which air can diffuse or leak through a unit area of material induced by a specific pressure differential (for example 75 Pa or 1.57 lb/ft2). ASTM E 2178 and ASTM E 283 are test methods used to measure air permeance. Units are L/s•m2 (ft3/min•ft2) with pressure reported as Pa (lb/ft2).


See also: AIR IMPERMEABLE, AIR PERMEABLE