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The National Technical Information Service acquires, indexes, abstracts, and archives the largest collection of U.S. government-sponsored technical reports in existence. The NTRL offers online, free and open access to these authenticated government technical reports. Technical reports and documents in its repository may be available online for free either from the issuing federal agency, the U.S. Government Publishing Office’s Federal Digital System website, or through search engines.

Details

Continuous Optical Monitoring of Asbestos in Air,

PB88247598

Publication Date	1980
Personal Author	Stolwijk, J. A. J.
Page Count	8
Abstract	A continuous optical monitor for the identification and counting of asbestos (1332214) fibers in ambient air, in occupational and residential environments was developed. Early designs consisted of a fiberglass tube with an internal diameter of 1.0 centimeter and a length of 8 centimeters with four internal electrodes. A 2 milliwatt He/Ne laser was positioned down the center of the tube. External air was sucked into the tube and polarizable fibers caused to spin at the quadrature frequency reflecting the laser light at right angles to the long axis of the fiber. A photomultiplier captured the pulses of light generated and fed the data to a small computer. One drawback of the system was that fiberglass and samples of different types of asbestos produced output signals which were very similar. A new design was developed which employed eight electrodes made from round platinum wires. Long fibers were distinguished from short fibers by the narrowness of the beam reflected.
Keywords	Asbestos Air pollution Hazardous materials Fibers Lasers Air pollution monitors Occupational safety and health
Source Agency	National Institute for Occupational Safety and Health
NTIS Subject Category	68A - Air Pollution & Control 68G - Environmental Health & Safety
Corporate Authors	John B. Pierce Foundation Lab., New Haven, CT.; National Inst. for Occupational Safety and Health, Cincinnati, OH.
Supplemental Notes	Sponsored by National Inst. for Occupational Safety and Health, Cincinnati, OH.
Document Type	Technical Report
NTIS Issue Number	198823

Continuous Optical Monitoring of Asbestos in Air,

Continuous Optical Monitoring of Asbestos in Air,
PB88247598

Publication Date	1980
Personal Author	Stolwijk, J. A. J.
Page Count	8
Abstract	A continuous optical monitor for the identification and counting of asbestos (1332214) fibers in ambient air, in occupational and residential environments was developed. Early designs consisted of a fiberglass tube with an internal diameter of 1.0 centimeter and a length of 8 centimeters with four internal electrodes. A 2 milliwatt He/Ne laser was positioned down the center of the tube. External air was sucked into the tube and polarizable fibers caused to spin at the quadrature frequency reflecting the laser light at right angles to the long axis of the fiber. A photomultiplier captured the pulses of light generated and fed the data to a small computer. One drawback of the system was that fiberglass and samples of different types of asbestos produced output signals which were very similar. A new design was developed which employed eight electrodes made from round platinum wires. Long fibers were distinguished from short fibers by the narrowness of the beam reflected.
Keywords	Asbestos Air pollution Hazardous materials Fibers Lasers Air pollution monitors Occupational safety and health
Source Agency	National Institute for Occupational Safety and Health
NTIS Subject Category	68A - Air Pollution & Control 68G - Environmental Health & Safety
Corporate Authors	John B. Pierce Foundation Lab., New Haven, CT.; National Inst. for Occupational Safety and Health, Cincinnati, OH.
Supplemental Notes	Sponsored by National Inst. for Occupational Safety and Health, Cincinnati, OH.
Document Type	Technical Report
NTIS Issue Number	198823