Document ppJmRrKvJnKOERJmX0O4ED54X

U Largent - KZO Dr. J. M. MacMillan - HO M. R. Baker - Tllo Company Feb. 7, 1968 Observations were made at Tllo Coopan?, Inc., Stratford, Connecticut, on January 11, i960. Air was sampled for particulate loading at the raw materials feeding station on the second floor directly above the asbestos slurry tank* Mo other measurements except visual observations were made. MOULTS The dust found In samples In lapinger flask liquid used to sample during the operator's cycle of about 20 minutes west Mo* 1 1*4 million particles per cuble foot. Mo. 2 5*9 million particles per cuble foot. In the areas where stone granules and mica are applied to opposite sides of asphalt sheeting, there was gross evidence of dustiness. However, the equip ment was not In operation due to repairs, so no air sampling could be done. Sound pressuree were extremely interestir* In certain areas, particularly near a large vacuum pusqp* There may be no hasard to hearing here, but there could be near the log shredder at the start of the process in the felt mill. jttetb noise and potential dustiness were observed nej^the machine that puts the finished edges on The current controversy about a suspected rela tionship between inhaled asbestos and oaneers of the lungs and peritoneum justifies oareful and continued survellanee of any and all usee of asbestos, and the shaping (like sawing, grinding, etc.) of asbestos pro ducts* One school of thought blames only crocldollte R M C0800280000340 Dr. J. N. MacMillan Pags 2 February 7. 1968 (aebeatos fibers) and exonerate chrysolite (asbestos fibers), but others are Inclined to indict "asbestos4. The fact that only "long fiber" chrysolite asbestos is used at the Stratford plant la fortunate, no doubt. The dust found in samples No. 1 and No. 2 was so little as to seen non-hatardous so far as asbestosIs (as distinguished from cancer production) is concerned. Under the microscope, no fibers were seen that had the characteristic appearance of asbestos fibers and this suggests* (l) the dust was all either cement or limestone (both are added along with asbestos to make the slurry), or (2) the asbeetos fibers were present but so slender, say 0.01 to O.lp. in diameter, that even fibers 10 to 20u in length could not be seen using the standard methods of looking at dust with a microscope. The point of this part of the discus sion Is Intended to suggest that additional samples must be collected to confins, if possible, the possibility that few or no significant number of asbestos fibers get into the work area. Other procedures may be used, perhaps, to greater advantage for this purpose. Sample No. 2 was unusual because the operator, while per forming the routine operation of filling a conveyance by shov eling into it a proper amount of ground scrap shingles, caused a high section of the serap to cascade to the floor generating a brief but heavy cloud of dust. This probably accounts for the greater amount of dust found In this sample, since no similar episode accompanied the earlier wortc cycle during which Sample No. 1 was collected. Uhless there was a significant but unde tected number of asbestos fibers In these samples, there need be no great concern about dustiness near the slurry tank. Additional samples need to be collected to adequately appraise the Jpftsmtlal dustiness of the manufacturing processes at the StratMs# plant. Noise level measuriants should be made during same future visit to the plant. ldward J. Largant RM C0800280000341