Document gyjMm8zxvxj2ZrrVGYxrOBqq

ST0000868 '- / 3370 THE DOW CHEMICAL COMPANY PITTSBURG January 27, 1971 Harold R. Hoyle 1701 Bldg. Midland cc: D. H. Clegg, Pittsburg ASBESTOS Dr. Leroy Balzer of University of California at Berkeley reported on recent conferences on asbestos at the December AIHA bimonthly workshop: 1) Ralph Nader recently testified before Congressional Committee on asbestos and toy balloons. i 2) Great Britain has outlawed asbestos from approved insulation. t 3) Darlington Industries in England has Ca Silicnte asbestos-free insulation. -- 4) San Francisco now has spray insulation regulations: 5 fiber/cc at breathing zone, 1 fiber/cc in general spray area, and 100 fibers/iiter outside protective drapes. Tests on background fibers give G.2-1 fibers/iiter. Numbers set on very little data. 5) Power cutting of bound asbestos board gives significant exposures. 6) Tremolite (coarse talc) contains significant amounts of asbestos. 7) Liquid implantation of fiber glass and almost any inert material can produce cancer in tissue, but none shown by inhalation studies. I discussed counting methods with him since we are counting at X63 instead of X400. He indicated no asbestos experience with lower magnifications but had experienced detection limits not too much changed with 10-fold change example from X10 to X100. U3 was interested in securing report on my asbestos survey. Under what circumstances would we release such information? L. Pitchforth, ^Jr. Industrial Hygiene moh