H. M. Jackson to Arthur Elsenbast on Dust from Hy-Sorb Floor Absorbent (1952)

Two memoranda from Hugh M. Jackson, Johns-Manville's safety engineer, to Arthur Elsenbast of the Celite Division about Hy-Sorb, an absorbent spread on factory floors to soak up oil and grease. On December 3, 1952, Jackson reported on visits to five customer plants to see how the material was applied and cleaned up, and judged that dust exposure there was "far less severe" than in J-M's initial tests and, as observed, "negligible." For further evaluation of "the hazard potential" he recommended X-ray diffraction tests for crystalline silica, controlled dust measurements, and drop tests in a chamber like one used by the Eagle-Picher Company, to compare with its product. The December 23 memo records the plan agreed at a meeting on December 18.

In Johns-Manville's chronology

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

Memos regarding J-M's concern about the hazard to consumers when using J-M Hy-Sorb product, dated 12/3/52 and 12/23/52. J-M conducts sampling tests and tries to improve handling methods which it will recommend to customers. Eagle-Picher has a similar product. J-M writes to Eagle-Picher regarding the safety of its product. Hy-Sorb is a silica-containing product.

Editor's note: J-M's description says J-M wrote to Eagle-Picher about the safety of its product and calls Hy-Sorb a silica-containing product. Neither memo shows a letter to Eagle-Picher; they mention only a test chamber like one Eagle-Picher used, and they plan tests to learn whether Hy-Sorb contained crystalline silica.