Metropolitan Life Insurance Company, A Study of Dust Conditions in Raybestos-Manhattan's Manheim Plant (1930)

A 36-page report on the Manheim, Pennsylvania, plant of the United States Asbestos & Rubber Division of Raybestos-Manhattan, made in February 1930 by Metropolitan Life's Industrial Health Service, the third in its series on the asbestos industry and the first to examine workers. Fifty-four long-service employees were examined and 20 were X-rayed; ten showed "definite evidence of asbestos dust injury to the lungs." The report found that "Dust counts in the preparation room and carding room were high, several counts higher than ten million," and that the X-rays "definitely inform us that individuals exposed to the inhalation of asbestos will in time show structural changes in their lungs."

What it shows

The men with asbestosis had worked in twisting, spooling, carding and weaving for 5 to 22 years. The report says the number of cases was too small for final conclusions, and recommends better exhausts, vacuum cleaning in place of blowing dust off with compressed air, and physical examinations of all employees, with X-rays when indicated. It is part of the same Metropolitan Life series as the Charleston and Bridgeport and Stratford studies.

In Johns-Manville's chronology

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

Study of Dust Conditions in Manheim plant of Raybestos Manhattan conducted by the Industrial Health Service of Metropolitan Life Insurance Company during February, 1930. The purpose of this study was to determine the extent and nature of atmospheric pollution to which asbestos workers are exposed and whether there are harmful effects. The study included physical exams of employees. The impinger method was used for collecting dust samples; samples were also taken with the electric precipitator for particle size measurements. Graphs and charts regarding dust count results were included, as well as a discussion of work procedures.

The report concludes that the dust counts in the preparation room and carding room were higher than 10 million; individuals exposed to the dust in this area showed definite pneumoconiosis. The number of cases observed, however, was too small to draw final conclusions. The report recommends (1) the method of application of the oil used in the preparation room at the Charleston plant should be used since it is believed to more effective than the procedure used at Manheim; (2) continuation and extension of humidification and air conditioning systems; (3) repair and maintenance of the exhaust system attached to the machines in the prep room; (4) cleaning by a vacuum system instead of present system of blowing compressed air; and (5) provide initial physical exams to employees and periodic x-ray examinations to employees when indicated.

Related documents

• Metropolitan Life Insurance Company, Report on a Dust Survey of the Manville Plant (1929)