W. B. Reitze to D. Markusson on Exposures from Mixing Insulating Cements (1976)

A one-page memo of November 5, 1976, from W. B. Reitze to D. Markusson, copied to D. R. Christensen of J-M's Research and Development center, on Christensen's memo of October 19, 1976, about sampling at a simulated asbestos-cement mixing site. Reitze did not question Christensen's figures but pointed out that "conditions from job site to job site differ." From "considerable experience during my Selikoff days taking samples on various job sites where cement mixing was in progress," he reported that his own results "ran from 30 - 40 F/CC for large trough mixing and up to 80 F/CC for the small pail mixing operations which are probably far more common than the trough mixing."

What it shows

Reitze based his figures on job-site sampling from what he called his "Selikoff days," a reference to Dr. Irving Selikoff, whose studies of insulation workers are described in Selikoff Studies. His figures were many times the 3 to 6 fibers per cc that Christensen measured for trough mixing in an earlier simulation (Christensen's September 1976 tests), and dozens of times the 2-fiber limit then in force.

In Johns-Manville's chronology

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

Memorandum to D. Markusson from W.B. Reitze, 11/5/76, regarding Asbestos Exposure Mixing Insulation Cements; D.R. Christensen's memorandum to you -October 19, 1976. Reitze comments on the test results provided by D.R. Christensen on asbestos-cement simulated mixing. He points out that conditions during the 1960's would "vary from job site to job site." Reitze estimated that typical exposures for mixing of asbestos would vary from 30 f/cc to 80 f/cc.

Related documents

• D. R. Christensen to D. H. Markusson on Simulated 1960s Thermobestos Sawing and Cement Mixing (1976)