초록 ▼

Method is provided for non-destructively testing the integrity of a high efficiency particulate air filters using conventional equipment with a novel testing medium comprising an aerosol of hydrophobic-surfaced particles, which is non-toxic, efficient in measuring filter integrity, unaffected by moi

Method is provided for non-destructively testing the integrity of a high efficiency particulate air filters using conventional equipment with a novel testing medium comprising an aerosol of hydrophobic-surfaced particles, which is non-toxic, efficient in measuring filter integrity, unaffected by moisture and temperature conditions and non-coating of optics used in measuring, whereby more accurate measuring of HEPA filter condition is realized.

대표청구항 ▼

Method of non-destructively testing the integrity of a high efficiency particulate air filter having a frame and a filter pack sealed in the frame, said filter pack comprising a tightly packed axially extended alternating series of separators and parallel reverse turns of glass cloth along which a l

Method of non-destructively testing the integrity of a high efficiency particulate air filter having a frame and a filter pack sealed in the frame, said filter pack comprising a tightly packed axially extended alternating series of separators and parallel reverse turns of glass cloth along which a liquid tends to wick; said method including generating an aerosol in a gas stream of solid particles free of said liquid and having a hydrophobic surface and a mean average diameter of not more than 0.2 micron, exposing the filter to be tested to said aerosol under predetermined test conditions including a temperature at which said particles remain solid, and a pressure differential across the filter urging said gas stream aerosol through the filter. Method of generating an aerosol for non-destructive testing of a HEPA filter including coating silica particles having a mean average diameter of not more than 0.2 microns with an organosilane of more than 4 carbon atoms, and thereafter dispersing said silica particles in an inert gas stream.