Dr. Kenneth W. Smith to J. E. Morrison on Unloading Silica Flour (1948)

A one-page memo of December 1, 1948, from Dr. Kenneth W. Smith at Asbestos, Quebec, to J. E. Morrison on the health hazard of unloading silica flour. A check had shown the men raising considerable dust as they unloaded bags of silica flour from freight cars, which Smith judged a health hazard to be corrected. He asked that broken bags be cleaned up at once and handled more carefully, said the men should wear respirators if any dust was raised, and planned to have dust counts taken.

In Johns-Manville's chronology

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

Dr. Smith writes to Morrison, 12/1/48, regarding the health hazard while unloading silica flour. Dr. Smith advises that "[if any dust is raised, I believe that the men should wear respirators."