Document pm3wOQMENXep398Q8X4mqJank

' (MID i btuushomi ' E. I. du Pont de Nemours & Company ixesamuTto Chambers Works Construction Deepwater, New Jersey 0002s engineering department CONSTRUCTION DIVISION V&( 9/ February 20, 1968 Jeremiah R. Lynch U. S. Public Health Service 1014 Broadway Cincinnati, Ohio 451202 Dear Sir: Re: Dust Counting and Air Sampling Ve have been surveying our construction work environment to assure ve are taking adequate precautions where hazardous dusts might accumulate. We are particularly Interested in control of asbestos dust and fibers of respirable size. Our findings are satisfactory thus far; however, since some questions have been raised, our Adrian Linch suggested we solicit your opinion regarding the following: 1) We have counted to a resolution of 1.3 microns. Is this adequate or would you recommend resolution to .9? 2) We have been sending our samples to the University of Pittsburgh for counting. We would prefer t geographically closer facility. Can you recommend any qualified persona in the Philadelphia, Pa., or Wilmington, Del. areas, keeping in mind we ere interested in both total dust counts and asbestos fiber - dust only. 3) What is your opinion of the validity of the sampling procedure for dust collection as recommended by the Asbestos Textile Institute? (We are currently following this procedure). 4) la the "Midget Implnger" (which ie acceptable in the ATI Procedure) as accurate ae the Grsenburg-Saith device? We ere using the "Midget Implnger" with both aerosol power and electric pumps; this "Midget Implnger" le very convenient. We will appreciate any opinions or information you offer. Very truly yours. ec: Adrian Linch Chambers Works Daapwater, H. J.- LVTskat Safety Engineer BETTER THINGS FOR BETTER LIVING ... THROUGH CHEMISTRY DUP 0900953 SC-DP-02200