Document ga90zj74mm4eEgYjODdaqm2xe

FILE NAME: Keene (KNE) DATE: July 19, 1969 DOC#: KNE034 DOCUMENT DESCRIPTION: 1969 July 19 Report on survey to evaluate employee exposure to dust containing asbestos KEENE CORPORATION MANUFACTURING DIVISION " COUNT! LINE ROAD VALLE! FORGE, ESNNSILVANIA July 19, 1969 PURPOSE: This survey was made to evaluate the employee exposure to dust containing asbestos used la the manufacturing operations. The principal areas evaluated were the Batch Department and the Cutting Departments. CONCLUSION: The results of the dust samples sent into our laboratory at the first of the year indicated that this dust did not contain any free silica, It did have the amorphous silica dust vhich carries a Threshold Limit Value of 20 million particles per cubic foot of air, and found in this dust is fibrous asbestos material which constitutes the major hazard to employees working in these manufacturing operations. The results of the dust samples which were taken for asbestos indicated that the Asbestos Loading Station in the Batch Department exceeded the Threshold Limit Value for asbestos fibers and that areas in the Cutting Department approached this limit. Overall control at this Loading Station should be im proved and there is no doubt that during certain times in the Cutting Department excessive dust exists and should be controlled through the use of a very good respirator program. In the case of the one station in the Batch Department, better enclosures and improved exhausting should be done. CONTACTS: - _ Mr. E. R. Hillham, Production Control Manager, was contacted during this visit. Mr. W. F. Heim, Engineering Representative from our Philadelphia Engineering Department, assisted in taking the samples and performing the survey. ' ' PROCEDURES: . ' Two methods for collecting dust since an overall evaluation of the total dust is necessary from the standpoint of amorphous silica and an evaluation of the asbestos were both needed. The first method collects dust samples by means of midget impingers utilizing distilled water as the collecting medium. The sampling rate was 0.1 cubic feet of air per minute. Ten minute intervals were used where the operations permitted. Dust counts were then made on a light field as recommended by the U.S. Public Health Service method for dust techniques. X 0347356 The second method including collecting airborne samples of dust on membrane filters in the the same locations. A sampling ^ t e of 20 liters of air for a 20 minute interval was used. The asbestos fibers were then counted as determined by the Membrane Falter Method at U30 X phase contrast magnification. Also a .': recommended D.S. Public Health Service method for dust techniques. RESULTS; The results of the sampling for dust in air are given in Appendix A. CRITERIA; In the study of occupational health hazards, certain guides are used evfl^tion of the exposures. These values refer to^TLY1s or Threshold Limit Values which have been adopted by the American : ^ ^ enCe ^ G o v e r n m e n t a l and Industrial Hygienists. They represent conditions under which it is believed that nearly all workers may be repeatedly exposed day after day without adverse effect. These limits should be used as guides in the control of health hazards and conditions ^ regarded 83 fine line3 between safe and dangerous S M i * 0*?8 ?i-,dU3t containing asbestos, the present Threshold Limit V ^ 1 *1 ** oi Per cubic feet of air, as h? bhe standard impinger light field count technique. The is being developed and is presently ^ f r ! ? ? ^ f ^ VhBr!b y .12 fibers n e a t e r than five microns in length of A30LT ^ h i er f fir^ 3 deterndned ^ the membrane filter method c u b S f i n f ^ r ?ontrast magnification or two million particles per eoiTn+ + UrS* air TS counted by the standard impinger light field l a t t L meth^Ts * ^ thiS survey> both methods were used since the . 13 a ^ mebhod based only on asbestos fibers, however its utilisation17 ***** the d8t8 background necessary to fully evaluate DISCUSSION; ' fib^ DePa5 tmnt> a very high concentration of asbestos S J d i n / S ? f ? TM 4 dJJ?ng the loading of asbestos at the Asbestos loading Station. This is a short duration operation but due to the extremely high concentration of asbestos fibers found here it is recommended that this Loading Station be controlled better aidosing the Station and actually providing an enclosure over the belt extending from the operator is needed. During the sample acrls thted tHai dus* from the Lime Loading Station actually^rried th! room inta the Loading Station area. Better b a l a S i ^ T J f d these systems should be done. K 01 X 0347357 In the Cutting Department, the highest fiber count determined was ' ~ at the Block Sawing Operations. However, this was slightly below the Threshold Limit Value for asbestos fibers greater than five microns in length. There would most likely be times when excessively high dust concentration would be in this area as well as other sawing operations. For this reason, it is recommended that a strong respirator program be provided for the employees whereby employees would be issued respirators in closed containers to keep them clean until they are used. Their use should be where controls are presently not sufficient and where a short duration high concentration of dust exists. This respirator program should include washing the respirators at night and issuing clean respirators daily to each employee. . The total dust count which would be comparable to the amorphous silica having a Threshold Limit Value of 20 million particles per cubic foot did not in any of the sampling area exceed this limit. The main hazard is asbestos fibers and therefore the recommendations submitted are based on this material. RECOMMENDATIONS; A. Batch Department - Asbestos Loading Station should have better control of dust at the source. Included in these improvements should be: 1. Better enclosure of conveyor extending six feet or more up the belt from the operator. 2. Balance of the exhaust system so dust is not pulled from the Lime Loading Station when loading the asbestos. B. Batch and Cutting Departments - A strong respirator program should be used in areas where engineering controls are not now effective and where there is short duration high airborne concentrations of dust. This program should include providing washed and clean respirators to the employees daily. X 0347358