Document MGbKEr30pEDe0DjXGBQmqd47M

inn DOW CHEMICAL U.S.A. 50983____________________________________________________________ TEXAS DIVISION FREEPORT, TEXAS 77541 c ENVIRONMENTAL HEALTH REPORT AIRBORNE ASBESTOS CHLORINE 3 BUILDING B-624 file no--B6-835 March 15, 1976 DATE. AUTHOR H. N. Edwards CHECKED MuJDATE . A74, Summery Airborne asbestos levels were determined downwind of a sandblaster cleaning pipe that had been previously coated with asbestos. Workmen in the area were probably not overexposed to asbestos but may have overexposure to other particulate matter. It is recommended that when sandblasting an area extending from 25 yards upwind to 100 yards downwind of the blasting, proper respiratory equipment is required. It is further recommended that anytime asbestos is removed from piping in large quanties, the area should be monitored before, during,and after removal. Di striburion 5. F. Edquist B-2401 R. E. Flake B101 D. C. Nefzger B-624 6. F. Schumm B101 Robert Woods B-624 jFLle 390716 AN OPERATING UNIT OF THE COW CHEMICAL. COMPANY *i qc i nn i s File B6-8 35 -2- March 15, 1976 INTRODUCTION At the request of supervision asbestos samples were collected downwind of a blaster who was cleaning pipes that had been previously covered with asbestos. These samples were collected February 9, 1976. METHODOLOGY Airborne samples were collected by pulling air through a Millipore filter AAWG 03700 using a Bendix Micronair pump {Bendix Corp., Baltimore, Md.). Air flow was calibrated at 1500 cubic centimeters per minute and sample times were 30 minutes. All analyses were done by Lee Martin of Central Laboratory B-1225 RESULTS The results are shown in Table I. At five feet downwind of the blasting, the level was only 0.416 fibers/cc. This is not a high level. DISCUSSION The fiber levels were not high, but other particulates were. Since the blaster was using sand there were many other particles. The concentration of these particles were not determined, but the area was roped off and a respirator required within 100 yards downwind. CONCLUSION Workmen in the area are not overexposed to asbestos, but are probably overexposed to other particulate if a respirator is not used. RECOMMENDATIONS 1. When sandblasting is necessary an area around the blaster should be blocked off and proper respiratory equipment should be used by these workmen who are required to be in the area. This area should start 25 yards upwind of the blaster and extend at least 100 yards downwind of the blasting. The area should become wider downwind. 2. If asbestos is present, the area should always be monitored and workmen should use a respirator. Possible other protective equipment may need to be used if determined by the survey. EHS HNE/bbs 3-15-76 TABLE I AIRBORNE ASBESTOS CHLORINE 3 LOCATION FIBERS/CC > 1. Five feet from blaster---------------------2. Ten yards from blaster---------------------3. Fifty yards from blaster-------------4. Seventy-five yards from blaster-- 0.416 0.128 0.018 0.006 All measurements taken downwind. $10014585 3907i8