Document NGwkjEjn3JpK0qe98da70M7vg

GRACE 0^33835 Construction Products Division TO: Ventdculite Hazard Evaluation File DATE: July 24, 1985 FROM: OC: S. Venuti SUBJECT: R. J. Bettacchi/J. S. Hamilton H. C. Duecker/J. C. Yang R. C. Ericson H. A. Eschenbach R. C. Walsh J. W. Wblter/W. R. Wright P. J. Walsh/H. T. Dudley Program Report #3 a Comparison of SCA (Standard Product) vs. SCA with Libby #2 Cyclone Fines added. Objective Manufacturing requested that an evaluation of SCA with Libby #2 Cyclone Fines added, be included in the Vermiculite Hazard Evaluation Program. The objective of manufacturing is to find a use for Cyclone Fines vhich currently represents a costly disposal problem. The actual evaluation involved a comparison of a single lot of standard quality Libby #4 SCA vs. the same lot of product with ~8% (by weight) Libby #2 Cyclone Fines added at the furnace. All product was manufactured at Tampa. Dust exposures were measured at a Commercial Roof Decks job in Pasadena, Florida. Results Vermiculite Type_________ Exposures at job site 8-hour time wgtd. avgs. Bulk Vermiculite Respirable Fiber Concentration (Procedure C-46) Libby #4 SCA/ Mix Charger Standard Product Mix Operator Fibers*** 0.406f/cc , Total Dust 5Cmg/mJ (9 minute sample) 0.050f/cc --------- 0.9ppm *Material Handler t0.166f/cc Libby #4 SCA/ Mix Charger with ~8% Libby #2 Cyclone Fines added Mix Operator V v , - 0.319f/cc 0.082f/cc 39.2mg/m3 (12 minute sample) 7.5ppm Material Handler 0.062f/cc NOTE: NOTE: The Material Handle!' spent less time deep in the trailer when Material with Cyclone Fines was used. (See Appendix tl). Dusty conditions made it necessary to change filters after only 2-36 minutes of sampling time. (See Appendix #3) OSHA Guidelines state that filters should be changed only after 1 hour minimun.