Lewis J. Cralley, Dust Sampling Instruments and Dust Standards in the United States for Asbestos (1969)

A three-page paper by Dr. Lewis J. Cralley of the U.S. Public Health Service, given at the International Conference on Pneumoconiosis held by South Africa's Department of Mines in Johannesburg, April 23 to May 2, 1969, with the conference title page. Cralley traced the American standard for asbestos dust from the first threshold limit value of 5 million particles per cubic foot of air, which counted all particles, "both fibrous and nonfibrous," to the 1968 proposal of the American Conference of Governmental Industrial Hygienists for a limit of 12 fibers per milliliter longer than 5 microns, or 2 million particles per cubic foot.

What it shows

Cralley wrote that "the fact that asbestosis was still in evidence in the 1960's" and the growing concern with cancer had renewed interest in the standard, and that exposures before the 1940s "often greatly exceeded" the old limit. He quoted the committee's view that "there is still asbestos disease appearing in industry," and noted the long latency of 25 years or more. The paper shows how the government scientist who was studying the asbestos textile plants explained the move from counting all dust to counting fibers.

In Johns-Manville's index

Johns-Manville's legal department indexed the Motley 1,000 in 1984. Its index describes this document as follows:

Article entitled "Dust Sampling Instruments and Dust Standards in the United States of America for Asbestos," authored by Lewis J. Cralley, submitted at the Department of Mines International Conference of Pneumoconiosis, Johannesburg, 4/23 - 5/2/69.

About this copy

This is document 328 of the Motley 1,000, from the set the Manville Personal Injury Settlement Trust's records facility certified as true copies, pages CRMC-Motley1000-Subj-001641 to CRMC-Motley1000-Subj-001644.