Document M4bV5qKk7obm9bKZ0QB2eRwOM

P' O' JI \ I (_L_r jj[_ February 7, 1967 Mr. D. L. Parker Dawborn Division W.R. Grace Company Waynesboro, Virginia Dear Mr. Parkert During our conversation last week, you requested information on air analysis for the determination of/_Aroclor Q260^Ln air. A description is given in the attached reprint. As you can see, this deals with Aroclor 1242 and 1254. These are diphenyls chlorinated to the respective percentages, as indicated by the last two numbers. Aroclor 1260 has a higher * chlorination. We are certain that if air concentrations are V'. kept to the threshold limit of 0.5 mg./cubic meter, no ** hazard is to be expected. I repeat what I have told you, that with the exception of in stances where prolonged breathing of the fumes evolved at high temperatures occurred, we have had almost no complaints referable to systemic damage. Care must be taken, however, V in engineering the installation. Local exhaust ventilation 1 should be provided if Aroclor fumes are evolved during the | process. If you have any further questions, please let me know. Sincerely, REK/ln att. R. Emmet Kelly, M. D. Medical Director 0158296 TOWOLDMONOQ54172