Document Z42N0YM9Nv16mOxYJyVBN1qDd

4, SHELL CHEMICAL COMPANY A DIVISION OF SHELL OIL COMPANY P. O. BOX 2633 DEER PARK, TEXAS 77536 September 6, 1978 Mr. Herb Mauck Payne 8 Keller, P. 0. Box 12S46 Houston, Texas Inc. 77017 Dear Mr. Mauck: Personal sampling to determine asbestos exposure levels is conducted periodically in the CA Unit during the mixing of the diaphragm slurry. The sampling is done in accordance with OSHA Asbestos Standard 1910.1001. Payne 8 Keller employees are involved in this task and as a result have been included in the monitoring program. An update of personal sampling results is attached. As you know, the OSHA Permissible Exposure Limits are 2.0 fibers/cc, 8-hour time-weighted average, and 10.0 fibers/cc, ceiling limit. The careful work procedures outlined when mixing the diaphragm slurry have been success ful in maintaining asbestos concentrations below the ceiling limit. However, as a precaution, employees are also instructed to wear the 3M brand dust respirators to avoid any exposure. Since the slurry preparation seldom requires more than S to 10 minutes, the employee's 8-hour TWA is much less than 2.0 fibers per cc of air. As our monitoring program continues, we will report additional personal sampling results for Payne 8 Keller employees. If you have any questions regarding these results, please feel free to contact me at 476-7374. R. P. Prutiger L. W. Horstman F. G. Reitz C. D. Russell J. D. Washburn JCentral Piles j Dictator Filey Monitoring Notebook Senior Industrial Hygienist LAWI 004222 DPMC-10308