Document b5rBo78ZxkLa0geyQgd9pnGgO

FILE NAME Owens Corning OC DATE 1937 DOC OC003 DOCUMENT DESCRIPTION Gov Report - A Study of Dust Control Methods in an Asbestos Fabricating Plant U. S. TREASURY DEPARTMENT HENRY MORGENTHAU Jr. Secretary PUBLIC HEALTH SERVICE w . THOMAS PARRAN Surgeon General A STUDY OF DUST CONTROL METHODS IN AN ASBESTOS FABRICATING PLANT BY RICHARD T. PAGE Assistant Public Health Engineer AND J. BLOOMFIELD Passed Assistant Sanitary Engineer United States Public Health Service REPRINT No. 1883 FROM THI PUBLIC HEALTH REPORTS VOL 62 210 45 November 26 1937 Page 1713 1727 OWENS CORNING FIBERGLAS CORP LEGAL & PATENT DEPT REC'D SEP 15 1941 | UNITED STATES GOVERNMENT PRINTING OFFICE : WASHINGTON 1913 me e Was wate he the @ wg wt kbthlltlltllef ee oe PLAINTIF'S PLAINTIFF'S PLAINTIFF'S EXHIBIT OCF ASBESTOS A STUDY OF DUST CONTROL METHODS IN AN STUDY FABRICATING PLANT BLOOMFIELD By RICHARD T. Proz Assistant Public Health Engineer and J. J. Passed Assistant Sanitary Engineer United States Public Health Service An extensive medical and engineering study of the health of asbestos workers has been conducted by the United States Public Health Service 5 The material contained in this ments the general study with a detailed study of thepadpuesrt scuopnptlreomethods used in an asbestos fabricating plant It is a present conditions and how they have been obtained and is rperpeosretnto edn as an example of the results of the application of scientific methods of dust control These data should be interesting not only to the asbestos industry but also to other industries having similar dusty processes The plant studied has only partly completed an extensive control program and conditions dust are being improved continually consequently these results should not be interpreted as representing the maximum possible efficiency in the control of asbestos dust but it is believed that they are representative of the best practice in this country at this time The dust control systems in use with the vari- ous processes in each department are described An analysis of employees is presented with a comparison ofoctchuepaattimoonsa-l pheric dust concentrations associated with controlled and similar uncontrolled processes FABRICATION OF ASBESTOS TEXTILEB minerals Asbestos is the class name for several different fibrous but the asbestos of commerce 1 is mainly the fibrous form of ser- pentine known as chrysotile Due to its fibrous nature flexibility and resistant properties asbestos fiber finds applications many practical One of its important industrial uses is in the manu- facture of resistant textiles to In the plant studied practically all raw material was crude Canadian or South African asbestos Some imported short fiber was used well as some of the short fiber salvaged in the recovery as but process most of the short recovered fiber was shipped other plants Signif- Scant variations in atmospheric dust concentrations due to the of fiber being processed were not evident in controlled grade processes in this plant Consequently the type of fiber used has not been con- sidered in the analysis of the data Each dust controlled tended to decrease the amount of dust generated in subsperqouceensts B.Mp540 B.Mp540 par- Chrystile la a bydrous magonlum late cent s^-xa43 percent magnesia and 129 parent water of fron e^ ^ usm dNumbem as well as magomium ) = 3,0.1180 containing 44.1 Other types of asbestos often contain silicatag 5 3 * e oe ee ttSe, i ome ta BATSi Bel e a DUST CONTROL IN AN ASBESTOS PLANT 3 processes These factors must be considered when comparing dust concentrations reportedin this plant with the data which have been reported for other plants ~ Approximately 300 persons were employedin this plant of whom 180 workedin departments having a potential asbestos dust hazard This study was confined to these departments preparation namely carding spinning twisting and and The occupa- winding weaving tional distribution of exposed workersis shownin table 1 TABLE Occupations and dust exposures of workers in an asbestos tatile plant Occupation Occupation NuNmbuermbeorf workers Average des copmote ton M. P. F. Normal Without ex | banat vanti istosa Preparation Crosbermes.openers Cotton openers Asbestos opests opests Bed bullders Ober -- -cseccnceccesee . Card tenders -. cer ewe cen e wenn een eene Wick tope and cosr e. ced eeeee Other Other .... Splacing twisting and ding spinners Muls and helpers spinners BpooleBpoole .. . Twisters Bpoole Twisters wlodere een cence Univerzal wlodere Others Weaving Weaving Weave: cloth Wet cloth Tape and Hating Creeles Inspectors Inspectore Others * eee - wees -- -- 1 acancee iT 18.4 a7 126 180. . Comba w1t 131 Comba 148 131 Comba 1.7 [ee Comba 1.7 |. ccccerewcce Comba .B neem Eltazon Eltazon Eltazon Eltazon Eltazon Eltazon + Eltazon 09 Lee wcerccene LO Joe 0.6 tea 13.9 60 11.0 10 . 2 Pana Pana Pana Pana 1.7 27 3.8 |...csceceweene 3.0 |... 1.8 [oo 18 ccwoeee ewww eens FILI 3.1 eee LI Jomnsonses vere * Dur aibsas system for this operation in^lde 1 Sample aher 1 Bample taken hour's operation operation without exhaust bin during loading METHOD OF STUDY This investigation included a study of atmospheric dust concentra- exhaust systems tions in the factory workrooms and a study of the used to remove asbestos dust workers Eighty atmospheric dust were collected at the samples level with the impinger dust sampling apparatus 5 breathing Sixty of these represented present working conditions and 13 represented conditions while exhaust apparatus had been turned off for 1 hour A collecting medium containing 25 percent ethyl alcohol in distilled water was found to prevent flocculation without causing excessive evaporation in either the sampling flaskosr the counting . Oe es ee ee A : san_5, a e . ee ee a a 4 DUST CONTROL IN AN ASBESTOS PLANT 4 All DUST were counted the after collection collection cells All samples counted to to low dust concentrations concentrations concentrations encountered encountered collection collection collection repre- repre- sented the from 20 3encoun0 tered encountered encountered most the samples cubic Samples were diluted distilled water and counted according the light field technique described by Bloomfield according A micrometer micrometer eyepiece having and equivalent one fourth the engraved engraved square square equivalent standard Whipple Whipple square used Since customary customary customary used counting the same volume volume of count only one quadrant the Whipple counted counted . impractical vent were burn volumes exhausted through each measurements measurements calculated from measurements of wood calculated in exhaust volumes line velocities Whenever Whenever Whenever same were noted between similar operation the average value is given were DESCRIPTION OF PROCESSES AND DUST CONTROL MEASURES Asbestos Cotton Asbestos received in burlap bags containing 100 Asbestos received received standard bales These pounds materials materials .. Cotton Cotton in preparation of asbestos are the plant Unloading Unloading storage and transportation of the yarn at this materials hazardous occupations The packed raw materials raw fiber to completed fabric fabric progress of the material fig ) Indi- individual processes processes shown by means of a flow sheet described and measures for dust control below are described below, PREPARATION DEPARTMENT DEPARTMENT Crushing Some of asbestos crushed fiber fiber but most of crude arrives received received no treatment treatment other other mining sorting and csrcurdeeesncrieennigng hacrsushlersatcrtuseherd type hand crushed from to replaced replaced in enclosed bags exhausted in any were were enclosed way the vents ion ion in preparation preparation department department was sufficient sufficient prevent concentrations near operation operation prevent concentrations concentrations of near near operation Crusher men res Crusher had men re e wee age: 4 os . Eg 2 SS DUST CONTROL IN AN ASBESTOS PLANT - 5 RAW MATERIALB OOT TTON TON CRUDE MILL ASBESTOS | ASBESTOS CRUSHERS RECOVERED MATERIALS { ROVING | WASTE CYCLONE & BAG HOUSE BAG SETTLING CHAMBER WASTE WASTE a COTTON OPENERS . y ASBESTOS OPENERS SCRENS VIBRATING SCREENS v MIXING < < ROVING REOPENER VIBRATING SCREEN Wy ELY WILLOWER WILLOWER AND WILLOWERWILOWER [ PICKERS MARKET STOCK BINS CARDING DEPT 4 WICKING i TWISTED CORD MACHINES CARDS . ROVING CARDS MULE SPINNERS RING SPINNERS ROPE TWISTING MACHINES . vv FOSTER WINDERS ( SPOOLERS) y CHEM TREATMENT8 TREATMENT8 BRAIDING DEPT COP WINDERS TWISTERS TWISTERS LOOMS % UNIVERSALI WINDERS CHEN TREATMENT RUBBER DEPT d INSPECTION INSPECTION INSPECTION . . Wos MARKET >| NOTE UNDERLINED PROCESBES HAVE DUST EXHAUST * Flotas 1. Prooms Low sbset asbestos tartije plant BYSTEMS pirators and usually wore them while loading or unloading the crushers The average exposure of a crusher man tending three es crushers was 3.5 M. P. P. F. A f ampl yemin the preparation department and all repairman and fandtors wars provided with ramples- ture of a type approved by the U. Burman of Mines Mines against high conmatrations conmatrations of fina sillos dust 3 fich Each opener bausted pasted the 1d6 beside velocity its own cyclone enclosed and enclosed vibrating screen One screen two one the charging hopper drawing drawing cfm dis- charging drawing 400 cfm and over ons and one over the dis. Public Health Reports ReprNoi . n18t 93 8 (8 edutha tDOP, pat area .- oete ties POANREDuy IA ONvE 3) ro AR : NEyeyq , siehtr+ 6 Di neya; y oker Flotar Pickemrolding machine RoE tm oe - : i Se wxre tak Yiovax Fiber recovery process WWrve and albaling albaling stK PZhaO t) DUST CONTROL IN AN ASBESTOS PLANT 7 charge end of the screen and the stock car drawing 770 cfm The second screen had one bood only over the discharge and drawing 615 cfm Short fibers and rock particles passing the screens fell through & chute to the enclosed recovery conveyor Fiber failing to pass these screens dropped into a stock car Full stock cars were pushed to a platform scale and then to the mixing beds The same men charged the openers and filled the stock cars The average dust exposure of asbestos operators was 3.6 M.P.P.C.F. M.P.P.C.F. M.P.P.C.F. Cotton openers best grades of insulation contain very small amounts of cotton if any but in all other cases cotton fiber is mixed with asbestos fiber to improve its spinning qualities At this plant the batch seldom contained more than 15 percent of cotton by weight but as much as 20 percent cotton was used in lower grade yarns The stage Lowell cotton opener was provided with exhausts at three points 770 cfm of air were exhausted through a canopy hood over the feed lattice 270 cfm from the bottom of the primary opener and 1,120 cfm from the bottom of the secondary opener Opened cotton fiber was discharged into stock cars No samples were taken at the cotton openers but the operators average exposure was about 2.4 M. general air preparation department Weighed quantities of asbestos and cotton were placed in alternate layers in the mixing beds Occasionally layers of roving waste from the carding room were reopened and added to the bed Mixing was done in six exhausted booths each 10 feet 2 inches deep by 6 feet 10 inches wide by 6 feet high Sides of the booths were permanent while the back consisted of a removable wood and canvas section Each booth was covered by a pyramid bood 32 inches high through which approximately 1,025 cubic feet of air per minute per hood were exhausted The velocity of air motion into these booths averaged 50 feet per minute during bed making and about 30 feet per minute during picker loading Dust concentration averaged 5.4 M. for the making operation After a bed had been placed the picker operator removed the rear partition of the booth and forked the batch into the charging hopper of a picker fig 3 The picker machine mixes the fibers in revolving beaters The four machines represented three different operations and two different types of exhaust systems The first machine not in operation during this study discharged mixed fiber into a stock car This material was then passed through a second picker for remixing The second and third machines discharged mixed fiber onto a belt conveyor which transported it to bins in the carding room The product of the fourth picker was carried to the carding room by a pneumatic conveyor Each of the first three machines had a hood over the charging lattice exhausting approximately 500 cfm a pipe exhausting about 1,650 cfm from the bottom settling chambers ---- DUST CONTROL IN AN ASBESTOS PLANT under the main picker drum and a hood over the end of the discharge lattice exhausting about 400 cfm The fourth picker had the same hood arrangement over the charging lattice but had no bottom exhaust and the mixed fiber was removed by a pneumatic conveyor exhausting approximately 2,000 cfm of air at a velocity of 2,550 feet per minute The picker operators wear respirators during the charg- ing operation Dust concentrations during picker charging varied from 4.0 to 9.5 M. averaging about 6.7 M. Recovery processes roving from the card room was returned to the preparation department for reopening The roving reopener was exhausted only from the pit below the last beater but the 1,780 cfm of air drawn through this hood were sufficient to prevent the escape of dust through the discharge lattice | The dusty air collected by the exhaust systems in the preparation and carding department was blown into a large settling chamber occupying two stories in the end of a separate building Air was displaced from this room to a house occupying the second floor on the other end of this building Dust was filtered out by burlap filters stretched on frames The filters were beaten down by hand daily during the noon rest period The collected dust was removed during the week end down and stored in bins in the preparation department house dust was screened on a completely enclosed and exhausted vibrating screen background fig 4 and the long fibers were removed to a cyclone collector by a pneumatic conveyor The dust from the settling chamber the long fibers from the house dust and fibers separated by cyclones on the exhaust lines from the spooling operation and the weaving department were passed through a willower and vibrating screen fig 4 Approximately 250 cfm of air were exhausted from the top of the charging lattice and 620 cfm from the discharge side of the opening drum Dirt passing the screen dropped onto an inclined tray and was removed by an exhaust hood drawing 730 cfm Fibers which did not fall through the screen were removed by the hood at the lower end of the screen 1,710 cfm and pneumatically conveyed to a cyclone collector Rock and other im- purities not picked up by the pneumatic conveyor fell into a waste box below the end of the screen The market for recovered fiber is limited and such fiber is usually too soiled for use in grade textiles Consequently only part of the collected dust was passed through this process Average exposure of operators was estimated at between 3 and M. C. As a measure of the effectiveness of the dust control system in the preparation department the exhaust fans were shut off for hour Pneumatic conveyors remained in operation Dust - concentrations increased steadily to about 50 M. P. P. C. F. at which time the exhaust fans were turned on The samples taken during this period vr w m_purr a iat mem Aw, ae ataat . DUST CONTROL IN AN ASBESTOS PLANT 9 were only a partial measure of uncontrolled conditions since the hoods - and enclosures had a definite control value While the location and design of hoods were the most important factors in dust control in the preparation department general ventila- tion helped prevent high dust concentrations This department occupied approximately 320,000 cubic feet of space from which ap- proximately 34,650 cfm of air were exhausted Consequently 6.5 air changes per hour were produced by mechanical ventilation which was supplemented by natural ventilation through doors windows and roof ventilators Fortunately beating was not a problem in this plant ra CARDING DEPARTMENT Mixed fiber from the preparation department was dropped from pneumatic or mechanical conveyors into bins in the carding department The total volume of exhaust from four bins was 6,850 cfm the major portion of this air being drawn through the one or two bin doors left open during the loading of carding room stock cars Dust concentrations as bigh as 40.4 M. P. P. C. F. were measured inside an active bin while the dust concentration just outside the door of the same bin was only 4.6 M. P. P. C. F. Workers classed as stock rollers fork the mixed fiber from the bin into stock cars This operation is supposed to be performed with both stock car and stock roller outside the bin door This rule of keeping out of the bins should be strictly enforced However stock rollers wearing respirators like to push their cars under the chute and then climb into the car and down the stock The cards are machines having a series of revolving cylinders wound diagonally with strips of leather set with fine sharp steel bristles a Carding removes remaining small bits of rock and combs the fibers into a more or less parallel condition to facilitate spinning At the time of this study 31 roving card units and 2 wicking cards were being operated A roving card unit fig 5 consisted of two cards a breaker or primary card and finisher or roving card The mixed fiber was fed by hand from the stock car to the feed hopper of the breaker card The stock roller wore a respirator during this operation The fiber passed through the breaker card emerging as loose blanket or web It was carried to the finishing card by a lattice conveyor or camel back The fiber was stripped from the last cylinder of the finisher onto a moving leather apron where a set of reciprocating rubbers condensed it into loose rovings of unspun yarn These rovings are wound on long jack spools to be taken to the spinning department The rovings at the extreme ends of the cards cannot be used for spinning because they lack uniform thickness and These rovings are collected by two small hoods pneumatically conveyed to a collection bin for return to the preparation department AS ae a eae 10 DUST CONTROL IN AN ASBESTOS PLANT The exhaust system applied to roving cards is shown schematically in figure 7. The quantity of air exhausted varied from 1,100 cfm to 1,800 cfm on different carding units with an average exhaust of 1,440 cfm per unit Cards are partially enclosed and only sufficient air is exhausted to prevent the escape of dust Each breaker card is exhausted at three points Hood B exhausts from the top of the feed hopper over the feed apron This hopper was enclosed and covered the cover being lifted during filling About 160 cfm of air were exhausted through the hood Hood A exhausted the top fly from the enclosure covering the main carding cylinder Hood CAMEL BACK CONVEYOR AUT 4 } | Ko) =< 5 Cc ~~. A aa OF ; BREAKER FINISHER SST ae a" TH 80 ju {TTT - 80 FEED BOY COVER Fionart Fionart Schematic plan of card exhaust system or C exhausted the bottom fly from the settling chamber under the carding cylinders Approximately 285 cfm were exhausted through each of these hoods The finishing card had four exhaust connections besides the two small hoods G which removed the waste roving Hoods E and F correspond to hoods A and C respectively on the breaker card providing an exhaust of approximately 285 cfm each The doffer card cylinder doffer combs and roving apron exhausted from below through hoods D and D at 70 cfm each About 40 cfm were exhausted through each roving collector DUST CONTROL IN AN ASBESTOS PLANT 11 The volumes of air exhausted through each hood were estimated on the basis of pipe areas Actual volumes showed wide variations on different units Single cards were used in the manufacture of asbestos wick andrope since a thick roving was desired The wick or rope was twisted from the unspun roving The wicking cards were exhausted at three points Approximately 380 cfm of air were drawn from under the feed lattice 490 cfm were exhausted from the top of the main cylinder cover to remove the top fly and 550 cfm were exhausted from the bottom- fly settling chamber ; Dust concentrations during carding averaged 1.7 M. P. P. C. This was also the average exposure of wicking card operators and wick and rope twisters Samples taken Dear the carding department | weight scales showed less than Card rolls were cleaned and ground at night except in cases of emergency Cleaning was done with hand scrapers made of strips of card cloth and the card cylinder was turned by hand Grinding was done with the usual type of card grinders The large roll was ground in place in the carding machine Slightly greater quantities of air were exhausted during grinding due to the decreased loss of head resulting from removal of the wooden card covers The small card cylinders were ground in a grinding frame These frames were partially enclosed and covered with a canopy hood exhausting 2,330 cfm per grinder Dust concentrations averaged 0.65 M. P. C. F. during grinding A special run of a group of carding machines made with all exhaust ventilation turned off and windows closed showed that dust concen- trations steadily increased At the end of 1 hour the concentration was 62.4 Under normal operating conditions about 64,000 cfm of air are exhausted from the carding department This is equivalent to about 5.5 air changes per hour disregarding natural ventilation through windows on all four sides of the room Spinning twisting and winding yarn as roving is twisted or spun into compact threads on either mule or ring spinning frames In this plant most of the spinning was done on mule spinners The spun thread was transferred from the spinning spindles to spools on Foster winding machines spoolers Spooled thread to be used as filler or woof in woven cloth was rewound on a cop winder into cops which will fit into the loom shuttles The remaining spooled thread was respooled on twisters which twist several threads into a yarn The number of strands used determined the size of yarn Both plain y and metallic yarns were twisted Metallic yarn contains one or more strands of fine wire Part of the twisted yarn was used in cloth weaving while the remaining yarn was rewound on Universal winding -- - frames for the market ed 12 DUST CONTROL IN AN ASBESTOS PLANT Mule spinning wes separated from other operations in this depart ment by partial partitions Natural ventilation was good and no exhaust systems were used The average dust concentration was 0.85 M. P. P. C. F. with a maximum of 1.3 M. P. P. C. F. recorded Ring spinning cop winding and Universal winding machines were located in the same room with the twisting machines Average exposures in the first three operations which were not themselves especially dusty were due to dust from the twisting operation With the exception of a trial exhaust system on one twister the remaining machines were not provided with exhaust The trial system was reported to be satisfactory and is to be installed on all twisting Thorax Thorax Echomatic views of exhaust system applied to Foster loder machines In this system the bottom of the twisting frame was enclosed and a total of 1,700 cfm of air per machine was drawn down ward past the twisting yarns and through five conical hoods distributed along a central exhaust duct Average dust concentrations at the various operations in this room were ring spinning 5.0 M. P. C. .; cop winding M. Universal winding 2.8 M. P. P. C. F and twisting 11.0 M. P. C. F. with a maximum of 15.8 M. P. P. C. F. recorded beside a ~ twisting frame No accurate measurements of the efficiency of the exhaust system on the single exhausted twister could be secured but simultaneous samples on both sides of this frame showed a dust Public Health Reports Reprint No 1683 Fictaz -T'perbausted broad loom o_o printed PY Fictzz 10 Tablfeor inspecting calendaring and brushing woven cloth ) ow Sea y's mere ae,Caw 1 Ne Th oe 2 paseFATS: 4.yd o i f 4 < : } Padedes. eS %: { , DUST CONTROL IN AN ASBESTOS PLANT 13 concentration of 18.0 M. P. P. C. F. on the side toward the unex- bausted twisting frames and a concentration of 6.3 M. P. C. F. on the other side Four Foster winders spoolers were partially separated from the other operations by partitions fig 6 The exhaust system con- sisted of an individual conical hood around each spindle holder fig 6 Approximately 46.5 cfm were exhausted through each hood or a total of 9,270 cfm through the 200 boods on the 4 spooling frames Dust concentrations at the spoolers averaged 2.9 M. P. P. C. F. and increased to 9.6 M. P. C. F. within 30 minutes after the ventilation bad been shut off WEAVING AND INSPECTION Clotb tape listing and brake bands were woven on different types looms In this plant exhaust systems had been applied to the dry cloth loons since these were considered to be the most important source of dust The dust control program calls for installation of exlisust systems on dry tape listing and brake looms At present these operations are mainly performed wet or partially wet Brake looms were not in operation during this study Significant differences could not be noted between dust samples collected around the various tape and listing looms Dust concentrations ranged from 1.2 to 4.0 M. P. C. F. and averaged 3.0 M. P. F. Nineteen cloth looms were in operation in this department One of these was a wet loom not provided with exhaust boods 4 were dry looms provided with exhaust boods and the other 14 were so provided but could be operated either wet dry loom without exhaust hoods is shown in figure 9. The exhaust system is shown schematically in pre 11. A double exhaust hood drew air from under the warp while a second hood was attached to the top of the loom lay with exhaust ducts running down the side of each picker arm to an airtight swing joint at the bottom The openings in the loom hood consisted of four slots nine inches long by 1 inch wide extending over a space of 4 feet across the woven fabric at right angles to the warp A total volume of approximately 10,500 cfm of air was exhausted from the 18 hooded looms This averaged about 580 cfm per loom but since it was Beldom recessery to operate more than 10 dry looms at one time the average quantity of air exhausted was close to 1,000 cfm per loom Exhaust dampers were provided on all looms and a sufficient number to balance the system are closed on wet or idle looms The average dust exposure of a weaver operating a dry loom with exhaust was 0.7 M. while the average exposure in wet weaving without- exhaust was 2.6 M. Samples taken beside a dry loom without exhaust showed dust concentrations of 9.6 M. P. F. " e ad cumey wm - =m .. 14 DUST CONTROL EN AN ASBESTOS PLANT e after 45 minutes Average dust concentrations have been shown as 49.7 M. P. C. F. 5 during dry weaving Woven cloth was inspected brushed and calendered on the inspec- tion table shown in figure 10. inspec- Each of the driven brushes was _| A ( Plotas Schematic views of exhaust system applied to broad looms Approximately partially enclosed and exhausted of drawn through each of the two hoods at the fron7t50ofcftmhe taaibrle waenrde about 200 cfm were drawn through the cleaning hood at the back of Stee teens power sayy mean, 1 , em te DUST CONTROL IN AN ASBESTOS PLANT the table Dust concentrations M. A sample taken during while & 15 inspection averaged 0.5 roll of fabric was passed tion of 11.8 P. C. F. Doffing inspection and calendering of tape and operations and were not provided with listing were hand of 5.0 M. exhaust Dust concentrations were exposure was intermittent recorded during these operations but the Creelers had an placing spools average and exposure of about 1.3 M. P. C. F. while threading looms An exhaust of 12,200 cfm of air partment corresponding to was provided in the weaving de- In cold weather warm approximately air three air changes per hour from a plenum was distributed through the department system while in warm weather natural secured through use of windows on all four sides of the vdeenptialrattmioenntwas OTHER OPERATIONS Other operations in this plant consisted of yarn was chemically treated and processes in which the cally treating or rubberizing fabricated fabricated or processes for chemi- hazard was associated with these cloth No potential asbestos braiding machine used to processes with the exception of one make large diameter asbestos tubing This machine was covered with a conical diameter which provided an exhaust coafnopy hood about 6 feet in air A sample taken beside this machine approximately showed 200 cfm of of 0.4 M. C. F. at the a dust concentration concentration operators breathing level Table Volumes of air exhausted asbestos tpeexrtilemapclhanitne in various operations in an Operation Total concDeustncon-cen- Conneo-Conneo- tions volume hausts per cu ft./min |f with exhaust M.P.P.C.F. tration with- out exhaust M.P.P.O.F. Asbestos opener opener Vibrating screen .. 625-1,000 625-1,000 } MCiotxtionng opener 700 beds Picker Roving reopener Fly willower and screen Roving c e e RovingBreaker primary I 3 1 3 1 ty 2,160 1.025 2.570 2.570 1,780 1.800 3. 11. 1-34.0 |e 43. 8 43. 1-10.8 07 134.3-743 nn Pie fo. cl) ate cards primary = Finisher primary ) .-------------- Wicking 3 I 420 .-------------- , 420 .-------------- ee, 4 card .-------------- .-------------- 1 440 L7 .- - - - .------- } Card spoolers .-------------- Foster winders triton awe 3 , 420 1 2.330 02 es 6D Twisters broad looms ase 1 2225 [eccmeeennnence looms Wearing broad eon 1 1,700 1,700 07 13.1 feo. Calenderer 2 1.300 1.300 tee 11.0 3 . 49.7 1.850 1.850 Stl ' Equipped with pneumatic 11. * Unpublished conveyor exhaust through Fulton et data other conveyor conveyor . Ref plants J. M. Dalla U. P. . Individual cone for each spindle manifold connected to exhaust not included H. 9. e @ b Ad Say el . Y nny are ant . .e 4. . 01 500 0102 . erm Tt oe ee ee ee oe. wet 16 DUST ContTRoL IN <n AN ASBESTOS PLANT REFERENCES CEs (1) 1 Ries H. Tne, Inc. Ries New Watson Watson T. Engineering 1937 () Fulton Part Fulton W. Dooley and Houts .: Asbestosis fabricating Pennsylvania Sept. Part II The nature amount encountered encountered plants plants Spec Bull Pennsylvania No. Pennsylvania Pennsylvania Labor Industry Industry Dept. Labor (3) Pennsylvania M The determination deterdmienattioen rmination control Bloomfield Bloomfield Pub dust Pub Health No. 217. Govt and Washington IndustrialIndustrial ~&y Harding Health Health Willard A. BeatingPrinting and con, ic-on, i- con, i- (4) tioning Harding Wiley Wiley ventilation ventilation tioning tioning Unpublished Sons Inc. States Unpublished data United States Public Service Siliceous Public Rice S Siliceous dust relation relation Bull. Bull )1Page 3 R2 . Bureau new ocular micrometer (7) Pub Health Health Note Note new micrometer Pub. Pub Rep 62 1315-1316 1315-1316 1315-1316 Health 2: 1315-1336. micrometer for dust for Use in dug? counting . counting. O