Document 8O3Q3eBEw0EkXL51gZM1OOaNy

bee: February 12, 1975 RICHARD W. PHUDH _ EMPLOYEE HELATICHS DEPARTMENT SAFETY AND FIRE DIVISICN - N 12452 ENGPEERING STANDARD S4T - AS3ESTCS (Ref: Letter R. W. pruga to J. A. 2app, Jr. , 9/10/74) In reference to Section 7. Sacyling, proper collection of air samples ia the sain item in assessing the worker's exposure. The person evaluating the sample has to assume that the sasyle he receives is representative of the situation and must therefore rely on the ability of the person collecting it. The concept of an un skilled person doing air a anyling is not in keeping with Du Pant's usual pro cedure of excellence in health protection. Air sanyling for asbestos is a skilled procedure which requires training and judg ment. Training courses have been given within Du Pont. Similar courses are routinely available through SICBH. Assistance and guidance can be provided by either Haskell laboratory or Marshall Laboratory (T. Nelson). To treat the subject properly and in agreement with your statement, there would have to be considerable e^ansion of this section which I do not think is necessary at this time. In reference to 7. 1.1, please note that the Federal Register does not specify that sacyles must be taken at least every six months. The statement about taking a sample for a minimum of 15 minutes is misleading. There are many situations _ where 15 minutes is too long for a sasyle. A heavy dust deposit prevents proper evaluation of a sasyls and sometimes even five minutes is too long of a sample period for seme operations. The number "516" in paragraph 7. 3.5 is valid only for Marshall Lab. I question the usefulness of presenting this formula. A better concept could be obtained by saying: "If it's extremely dusty, sample for 5 to 15 minutes; visibly dusty, 30 minutes to 1 hour; and not dusty, up to 4 hours." ORIGINAL SIGNlO >T RICHAKG 1. I IUIAt Richard J. Hubiah Consultant Industrial fygiene >403 RJH/egg DUP 0903533