Document NEnypmNLnkEgOapY6dn0VKGYy

FILE NAME: Goodyear (GY) DATE: 1937 Apr DOC#: GY 100 DOCUMENT DESCRIPTION: Trade Journal Article - Talc Dust in the Rubber Industry TALC DUST IN THE RUBBER INDUSTRY COMMERCIAL talcs are highly variable in com position since they generally contain not only the mineral talc (hydrous magnesium silicate), but, in addition, natural mineral impurities such as dolo mite (lime-magnesium carbonate) and serpentine (hydrous magnesium silicate). These variations in composition are relatively unimportant to manu facturers because of the fact that the uses of talc depend more on physical characteristics than on chemical composition. In the rubber industry the chief use of powdered talc is as a dusting agent prevent pieces of unvulcanized rubber from sticKing together. Possible Health Injury b y CHARLES R. WILLIAMS Petrographer, Engineering Department Liberty Mutual Insurance Company * and other rubber goods. It is the purpose of this report to outline the findings of this survey. Method The data on which this paper is based were gath ered in a representative group of plants in the rub ber industry, which use talc as a dusting agent. Table 1 shows the products manufactured at each of these plants. When so used, talc is disseminated into the air in large quantities and the question has often been Plant A I raised as to the possibility of permanent lung It C ! i damage resulting from the continued inhalation of D B ! F such dust. There has been very little work done 0 i in connection with this problem. In two published II I TABLE 1 Product Insulated Wire Rubber Goods (all kinds) Rubber Hose & Tubing Automotive Cable Insulated Wire Insulated Wire Webbing Rubber Tlirend Rubber Thread studies of the effects of exposure to dust in talc mines and mills in Georgia and Vermont (one by In each plant data were gathered as to sources i Dreessen,1 the other by Dreessen and DallaValle2 of d ust; number and types of machines; nature of of the U. S. Public Health Service) the writers con ventilation, if any; number of employees; length cluded that tale does not produce disabling pneu of service in dusty operations and nature of work. moconiosis, although Dreessen found some evidence Air samples were taken with a Greenburg-Smith ! in his Vermont study (l,p.98) that the dust (70% impinger and counted standard light field tech talc) produces a "fine diffuse bilateral fibrosis of nique within a few hours of the time they were the lungs which is definitely demonstrable in the taken. There was probably some solution of car x ray." bonate particles, but a comparison of tables 5 and 4 In order to determine the possible dust exposure will show that the bulk of the carbonates were not i involved in the use of talc, the w riter undertook dissolved. Samples of the raw materials and the a-survey of plants engaged in the manufacture air samples were analyzed'Hby the petrographic of rubber tubing, insulated wire, rubber thread, meItnhoedvefroyr pmosinsiebrlael ccaosnetednatt.a are put into tabular I Dnt?8scn. W . Q.-- `'Eff*ct6 of C ertain Silicate D usts on tb Lun^s," Jo u r, ! form to facilitate comparisons between conditions lu d u n m l Hjgjene. Vol. XV, No 2. Mar. 1933 pp 6S-7S. t lirrxrweu, w . 0. and DaUaVaHe, J M --"Tbe Effects of Exposure to D ust m Two Creorgia Talc MiU$ and M ines." U. S Public H ealth Report at various plants. _________ Vol 00. No 5, pp, 131-143. i Eminent Industrial Physicians Are Recommending Sodium Chloride Experience with L ast Summer's Intense Weather Increased Attention to Heat Sickness The installation of Fairway Dispens ers at drinking fountains together with a supply of Fairway Sodium Chloride Tablets represenTs an ex penditure that is so slight it is nearly negligible. nnswarrrHmosuminimsK' [.wneu*nu*sstweeiKa* X d k U d . W iUp I M d A W A r f.x fS * * Industrial Physicians are pretty well in egreement that heat sickness, regardless of its manifestation, finds ifs cause in e deficiency in sodium chloride in the system. This deficiency can readily be compensated for by swallowing Fairway Sodium Chloride Tablets as thirst is quenched at the drinking fountain. The preventive value of Fairway Sodium Chloride Tablets has been tested and proved again and again. A very marked de crease and many total eliminations of heat sickness are re ported from mills, shops, and factories where Fairway Sodium Chloride Tablets are used. Write for "Prevention of Heat Sickness." FAIRWAY LABORATORIES, Inc. 2626 W, Main Street Belleville, III. Dust Concentration Table 2 gives a summary of the number of ma chines generating dust, ventilation, men exposed and dust concentrations in the various departments of these plants. Plant A B C D E F G H 1 Machines 12 3 3 4 7 4 3 6 3 1 1 9 1 1 1 i .. Venti* Department lation Insulating W Depanning (large wire) WF Depanning (small wire) W Depan ning W Tubing W Vulcanizing (depanning) W Mill Room W Tubing & Vulcanizing W Mill Room (cellar) Molded Hose W Depanning W Insulating W Depanning W Punning Depanning Spool Winding Mill Room Thread Department Thread Department ww Mill Boom Spool Winding ww Concentration Em- millions ployees cu. ft. exposed 64.2 26 169.0 14 71.G 14.3 20 46.0 22.0* 7 194.0 .. SI 5.3 92 11.7 11 28.0 3 13.3 4 81.0 13.8 41 144.0 4 7.8 $ 23.8 4 10.6 2 7.1 5 10.7 11 26 4 18 7.9 4 48.4 2 W --Windows. F--Fan in Wall. 300 *At plant B samples were taken under two groups of conditions. With both tubing and vulcanising departments, which are not phys ically separated, operating, the dust concentration in the vulcanising department was 194 million and in the tubing department 46 million When the vulcanizing department was not operating tbe concentration in tbe tubing department dropped to 22.6 million. This is an excellent example of contamination of w o rk ro o m a i r which co u ld be av o id ed by segregating dusty from non-dusty operations. It may be seen from this table that in three of the seven depanning operations (removal of vul canized rubber from its bed of talc) dust concentra tions are over 140 million and only one below 20 million. The concentrations in the extrusion (in sulating, panning) departments ranged from 8 to SAFETY ENGINEERING 64 million--the two highest 46(B) and 64(A) be ing in the same plants having the most dust in their depanning departments. In both of these cases there was no physical separation of the extrusion and depanning departments and much of the dust in the extrusion departments originated in depan ning operations. Three of the four mill rooms studied had concen trations below 10 million and the fourth, which was located in a basement with little ventilation, had a concentration of 28.0 million. In the processing of rubber thread, the dust con centrations were found to vary from about 10 mil lion to 50 million. Composition oi the Dust The wide variation in composition of talcs used in the rubber industry may be seen in Tables 3 and 4. Plant A B C D E F G H I TABLE 3 Petrographic Analyses of Baw Material (By count--less than 10 microns) % % less soluble than 10 Ser- Car- by weight microns Talc pen tine -bonate Quartz 41.73 95 6 5 86 7.95 90 32 49 9 tr. 35.50 90 12 35 45 tr* 28.18 90 18 15 62 tr. 40.03 95 21 33 S3 tr. 25.27 SO 6 S 82 22.94 90 16 26 47 tr. 5.08 80 27 57 9 tr. 3.50 75 38 50 8 Others 3 10 8 3 14 4 U 7 4 Plant A B C D E F G H 1 TABLE 4 Petrograpbio Analyses of Greenburg-Smith Samples (By count---less than 10 microns) % less than 10 microns Talc Serpentine Carbonate Quartz SO 15 12 75 50 36 42 8 t2r. 90 17 12 62 tr. 95 45 32 14 tr. 95 1 12 61 tr. 90 12 14 64 tr. 05 16 21 58 tr. 95 34 49 5 tr. 60 53 36 6 Others 29 IS 9 8 10 5 12 5 Table 3 shows that the mineralogical composition of the talcs being used (raw materials) and Table 4 the composition of talc dust taken from the air. The differences are slight and so it may be assumed for all practical purposes that the dust has essen tially the same composition as the raw material used. Little is known as to the toxicity of the silicate minerals present. Some authorities believe the carbonates are practically harmless, so it would seem reasonable to believe that the higher the car bonate content the less harmful the talc. The important factor to be noted in the above tables is the extremely small amount of quartz present in either raw materials or dusts. The paucity of quartz which may produce silicosis takes these dusts out of the class of dusts considered dan gerous such as granite dust or dust from other material with a high free silica content. Employees In the nine plants studied' there are 300 em ployees, who have been exposed to various concen trations of dust for different periods of time. Table 5 gives the proportions of employees exposed to FOR APRI L, 1937 various concentrations of talc dust. Approximately one-fifth of the men involved are exposed to over 50 million particles per cubic foot of air. TABLE 5 Employees Exposed to Various Dust Concentrations Concentration of particles per cubic foot Employees of air) exposed % Over 50 04 21.3 2i>~--5o 28 9.3 10--25 103 35.0 Less than 10 105 35.4 300 100.0 It may be noted from Table 6 that approximately 35% of all employees have been exposed to talc dust for 10 years or more. In the "over 30 year" group one man has been exposed for 44 years, one 45 years and one 55 years. Of those employees exposed to over 50 million particles of dust per cubic foot of air 50% have been working under dusty conditions for 10 years or more. TABLE 6 Over 30 years 25--30 20--25 15--20 10-->15 0--10 Less than 5 All employees 5 7 14 19 59 82 1H 300 Employees exposed to over 60 million 2 1 7 21 16 17 81 Summary Studies including dust counts and petrographic analyses were made in nine plants which use talc as a dusting agent. In these plants, 300 employees are exposed to concentrations of talc dust varying from 7 to 194 million particles (less than 10 microns in size) per cubic foot of air. The highest concentra tions were found in the tubing and vulcanizing de partments of rubber tubing manufacturers (50 to 200 million) and the depanning departments of in SI sulated wire manufacturers (generally over 100 million). In the mill rooms which, in these plants, were isolated from depanning or other dusty opera tions, the dust concentrations were generally found to be less than 10 million particles per cubic foot of air. In the manufacture and use of rubber thread, the concentrations ranged from 10 to 50 million. Of all (300) of the employees exposed, 195 or 65% were working in concentrations greater than 10 million and 64 or 21.3% in concentrations greater than 50 million. The talcs encountered in this study covered a wide range of materials. The contents of silicate minerals ranged from 14 to 92%, while the car bonate contents varied from 8 to 86%, by particle count in the respirable sizes. Recommendations 1. Handling of materials. It was noted an sev eral plants that considerable unnecessary dust was generated by careless handling of the talc. Control of this factor may minimize some exposures. 2. Isolation of dusty operations. Such operations as depanning which are sources of high concentra tions of dust should be located so that other parts of the plant may be kept free from such dust. 3. Raw material. Wherever possible the talc used should have a high carbonate content. 4. Insulated wire depanning. In the cases of smaller sizes of wire it is practical to cover the pan with a cone so that the wire comes out through an opening in the apex. This procedure is effective in minimizing the exposure. 5. Panning operations. Talc should be intro duced automatically, obviating the necessity of hav ing a man throw the talc in with a scoop or shovel. 6. Respirators. The use of respirators is recom mended for short exposures to high concentrations. POWERS RAPID X -R A Y FOR THE X-RAY EXAMINATION OF OHOUPS OF INDUSTRIAL EMPLOYEES SURVEY SEBVIC REDUCES THE COST OF CHEST RADIOGRAPHS TO WITHIN ECONOMICAL LIMITS Powers' Service is limited to the making and processing of chest x-rays on paper film at low cost, rapidly and satisfactorily, ior and under the direction oi, physicians, POWERS X-RAY PRODUCTS, Inc. GLEN COVE NEW YORK