A. Cromwell to S. A. Williams on Dust Collection at Lompoc (1932)

A three-page letter of December 28, 1932, from A. Cromwell, manager of J-M's Lompoc, California, diatomaceous earth works, answering S. A. Williams's memo of December 20. Cromwell lists the worst dust problems and how they were being cut: the dust exhaust from the cyclones "presented a physical hazard by scattering dust over the operations and through the living quarters of Mexican employees," and was being piped into old tunnels and a glory hole, trapped with water, and settled. "We conservatively estimate that the dust hazard and nuisance throughout our operations have been reduced by 75% since 1929."

What it shows

Packing and bag house work were "admittedly dusty operations," and the men there were required to wear respirators under the mill superintendent's instructions (Westmont memo, April 25, 1932). Lompoc recorded each respirator issued, kept a record of men in dusty places, and rotated them "at least every six months so their exposure will not be too great." Every employee had been examined once a year for five years, and examinations were to become semi-annual. The company was managing exposure at Lompoc as a known health hazard.

In Johns-Manville's chronology

Johns-Manville's own chronology of what the company knew describes this document as follows:

Memorandum from A. Cromwell (Lompoc) to S.A. Williams (HQ) 12/28/32 outlines the most severe dust problems at Lompoc "the dust exhaust from the cyclones presents a physical hazard by scattering dust over the operations and through the living quarters of Mexican employees, and a nuisance to surrounding property owners. Up until 1930, No. 2 Cyclones and occasionally some of the others also exhausted to the air." These conditions were in the process of being remedied and most had been eliminated by the time of the letter. It was estimated that dust hazards and nuisance throughout operations had been reduced by 75% since 1929. Respirators were required in some areas and "a record is kept on the personnel card of each employee to whom a respirator is issued. A record is also kept of the men employed in dusty places and the men so employed are rotated at least every 6 months so their exposure will not be too great. For the past 5 years we have made a thorough physical examination of each employee once each year. Arrangements have been made to conduct the examinations semi-annually in the future."

Related documents

• S. A. Williams to J-M Plant Managers Asking for a Report on Dust Control (1932)