Development and fabrication of a prototype fibrous aerosol monitor (FAM) (1977)

This 1977 report, prepared for NIOSH by the GCA Corporation, described a program to develop, design, build and laboratory-test two prototype instruments meant to detect and count airborne fiber-shaped particles in real time. The instrument, called the fibrous aerosol monitor (FAM), used a rotating electric field to make fibers spin and line up with the field. It detected them through the changing pattern of laser light scattered by the rotating particles, and it counted only fibers longer than a selectable length. According to the report, counting times of 1 to 1000 minutes allowed it to measure fiber concentrations between 0.001 and about 30 fibers per cubic centimeter. A concentration of about one fiber per cubic centimeter could be measured with a relative standard deviation of 10 percent over a 10-minute count. The FAM was portable and battery-powered. The authors described preliminary laboratory tests with crocidolite and chrysotile asbestos (printed "crysotile" in the text) and with glass fibers. They reported that the results indicated good correlation with the standard NIOSH phase contrast microscopy filter counting method. No human population was studied.

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From J-M's medical library

This copy comes from the Johns-Manville medical library. It was among the papers J-M kept in its medical library without an index entry.