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FILE NAME Talc TALC DATE 1937 Apr DOC TALC171 DOCUMENT DESCRIPTION Trade Journal Article - Talc Dust in the Rubber Industry !t . we . . sf Kee ee aise -3 eas, Bee os Seg. ie . on - edPaBel owtMidian ote TALC DUST IN THE RUBBER INDUSTRY COMMERCIAL tales are highly variable in composition since they generally contain not only the mineral tale hydrous magnesium silicate but in addition natural mineral impurities such as dolomite 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 to prevent pieces of unvulcanized rubber from stick- ing together Possible Health Injury When so used talc is disseminated into the air in large quantities and the question has often been raised as to the possibility of permanent lung damage resulting from the continued inhalation of such dust There has been very little work done in connection with this problem In two published studies of the effects of exposure to dust in talc mines and mills in Georgia and Vermont one by Dreessen the other by Dreessen and Valle2 of the U. Public Health Service the writers concluded that tale does not produce disabling pneumoconiosis although Dreessen found some evidence in his Vermont study p.98 that the dust 70 talc produces a fine diffuse bilateral fibrosis of the lungs which is definitely demonstrable in the x ray In order to determine the possible dust exposure involved in the use of talc the writer undertook survey of plants engaged in the manufacture of rubber tubing insulated wire rubber thread 1 Dreessen W Effects of Certain Silicate Dusts on the Industrial DroessenHygiene Effects Exposure 2 Georgia Vol XV No 2. and Valle Taic and 1933 Mar 1933 pp JM The 66-78 of Mines U. S Public No Mills Vol 50. 5 pp 131-143 Lungs Jour Exposure Health to Dust Report by CHARLES R. WILLIAMS Petrographer Engineering Department Liberty Mutual Insurance Company ek OU 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 gathered in a representative group of plants in the rubber industry which use tale as a dusting agent Table 1 shows the products manufactured at each of these plants TABLE 1 Plant it TA fora * Product Insulated Wire kinds Rubber Goods all kinds Rubber Hose Tubing Automotive Cable Insulated Wire Insulated Wire Webbing Rubber Thread Rubber Thread In each plant data were gathered as to sources of dust number and types of machines nature of ventilation if any number of employees length of service in dusty operations and nature of work Air samples were taken with a Greenburg impinger and counted standard light field technique within a few hours of the time they were taken There was probably some solution of car- bonate particles but a comparison of tables 3 and 4 will show that the bulk of the carbonates were not dissolved Samples of the raw materials and the air samples were analyzed the petrographic method for mineral content In every possible case data are put into tabular form to facilitate comparisons between conditions at various plants 3 a ee ete . SAFETY ENGINEERING Eminent Industrial Physicians Are Recommending j . Sodium Chloride Experience with Last Summer's Intense Weather Increased Attention to Heat Sickness The installation of Fairway Dispensers at drinking fountains together with a supply of Fairway Sodium Chloride Tablets represents an ex- penditure that is so slight it is nearly negligible ||| DISPENSER | Printing TABLET DISPENSER TABLET DISPENSER #! With lock iss and Ary | WithPrintiSntegll KAFUL SURE TO FACIFY STYLE HOPPER DESIRED Industrial Physicians are pretty well in agreement that heat sickness regardless of its manifestation finds its cause in a 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 decrease and many total eliminations of heat sickness are reported 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 Concentration Em- Plant A -- C Machines 12 13347 13347 13347 13347 + 363172 3631722 3631722 3631722 Department Insulating Venti lation W Depanning large wire WF Depanning small wire W Depanning Ww Tubing WwW Vulcanizing depanning < Mill Room BB Tubing & Vulcanizing BB Mill Room cellar - Molded Hose BBBB millions cu ft 04.2 169.0 71.0 143 Concentration ployees exposed 26 14 <e 20 46.0 22.6 z 194.0 .. a 5.3 92 11.7 11 28.0 3 13.3 4 ARE 363172 Depanning ARE 3631722 Insulating 363172 Depanning ARE 3631722 Punning 363172 Depanning OF 3631722 Spool Winding BBBB 81.0 Q BBBB 13.8 41 BBBB 144.0 4 7.8 $ 23.8 4 10.6 2 OF 363172 Mill Room s 71 5 . Thread Department Ww I : Thread Department w t Mill Room WwW . Spool Winding w 10.7 ih 284 18 7.9 4 49.4 2 Windows Fan in Wall 300 At plant B samples were taken under two groups of conditions With both tubing and vulcanizing departments which are not phys- ically separated operating the dust concentration in the vulcamzing department was 191 million and in the tubing department 46 million dropped When the vulcanizing department was not operating the concentration In the tubing department to 22.0 million This is an excellent example of contamination of workroom air which could be avoided by segregating dusty from 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 concentrations are over 140 million and only one below 20 million The concentrations in the extrusion insulating panning departments ranged from 8 to 64 million two highest 46 and 64 being 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 depanning operations Three of the four mill rooms studied had concentrations 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 concentrations were found to vary from about 10 million to 50 million Composition of the Dust The wide variation in composition of talcs used in the rubber industry may be seen in Tables 3 and 4 Plant ABCDEFGH ABCDEFGH ABCDEFGH ABCDEFGH ABCDEFGH ABCDEFGH ABCDEFGH ABCDEFGH 1 TABLE 3 Petrographic Analyses of Raw Material % soluble By% clegsount than 10 microns than 10 Ser- Car- by weight 41.73 7.93 35.36 28.18 45.53 2527 2527 22.94 508 3.56 microns 228358382 228358382 228358382 228358382 228358382 228358382 228358382 228358382 228358382 Talc 6 32 12 18 21 6 16 27 38 pentine 5 49 35 15 33 $ 57 57 50 -bonate 86 9 45 62 82 82 a7 9 8 Quartz ve tr. tr. tr, tr. ve ir. tr Aan Others 3 10 8 3 14 4 11 i 4 Plant A & Cc D E Fr G H I TABLE 4 Petrographic Analyses of Greenburg Samples By count than 10 microns % less than microns 84208 838 842088838 842088838 842088838 842088838 842088838 842088838 842088838 842088838 Talc ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT Serpentine ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT Carbonate ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT Quartz ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT Others ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT ITTIT Table 3 shows that the mineralogical composition of the tales 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 essentially 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 dangerous such as granite dust or dust from other material with a high free silica content Employees In the nine plants studied there are 300 employees who have been exposed to various concentrations of dust for different periods of time Table 5 gives the proportions of employees exposed to FOR APRIL 1937 51 various concentrations of tale dust Approximately 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 Millions of particles per cubic foot Employees Employees of air Over 50 250.00 10-25 Less than 10 exposed G4 28 103 105 00 21.3 9.3 350 354 300 100,0 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 Over 30 years 25-30 20-25 15-20 10-13 5-10 Less than 5 TABLE 6 Length of Service All employees 5 7 14 19 59 2 114 300 Employees exposed to 50 millmi ilo lin on 2 2 1 7 21 16 17 6-1 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 concentrations were found in the tubing and vulcanizing departments of rubber tubing manufacturers 50 to 200 million and the depanning departments of in- sulated wire manufacturers generally over 100 million In the mill rooms which in these plants were isolated from depanning or other dusty operations 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 tales encountered in this study covered a wide range of materials The contents of silicate minerals ranged from 14 to 92 while the carbonate contents varied from 8 to 86 by particle count in the respirable sizes Recommendations 1. Handling of materials It was noted in several plants that considerable unnecessary dust was generated by careless handling of the tale Control of this factor may minimize some exposures 2. Isolation of dusty operations Such operations as depanning which are sources of high concentrations 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 introduced automatically obviating the necessity of having a man throw the talc in with a scoop or shovel 6. Respirators The use of respirators is recommended for short exposures to high concentrations POWERS RAPID RAY FOR THE RAY EXAMINATION OF GROUPS OF INDUSTRIAL EMPLOYEES SURVEY SERVIC REDUCES THE COST OF CHEST RADIOGRAPHS TO WITHIN ECONOMICAL LIMITS ane an Powers Service is limited to the making and processing of chest rays on paper film at low cost rapidly and satisfactorily for and under the direction of physicians POWERS RAY PRODUCTS Inc. GLEN COVE NEW YORK