Document MZaNa784kEm3b2XxZ1L70jka

OLOGY [wL ZS, tu. I -ed no sigriccnat or NOTICE: THIS MATERIAL r ku; TECTED BY COPYRIGHT LAW (PLS^-ddd^t THE U.S. CODE. e: exposed dogs and naJities. The resuits /unction did not indicate A HEALTH SURVEY OF PIPE COVERING OPERATIONS IN CONSTRUCTING NAVAL VESSELS' Walter E. Fleiscbxr,1 Frederics J. Vnxs, Jr.,1 Robert L. Gade* and Pktli of the concentration oi| AN INDUSTRIAL health inspection of an felt and pipe covering in naval work are its low :lood cf exposed rabbits / \ important U. S. Navy Contract Yard thermal conductivity, light weight, strength, and ut. it exposed rats, mice and 'stance in the urine which red color when the urine Tags. ^ DCZltrSTS indicated that dustiness from miscellaneous pipe covering operations was considerable and that a few of the employees had what appeared to be asbestosis. This is a well-known industrial disease caused by only one thing--prolonged breathing of asbestos dust. The rtmiral manifestations are shortness of breath and an unusual chest picture refractoriness. When the felt and pipe covering were first developed, we were still building vessels under the Washington Treaty of Limitations in Tonnage, and every pound saved mean: that muca more armor, guns or ammunition fer a gives displacement, to say nothing of more economic operation for the weight involved in insulation. . r. Charles Sergo33er'for by X-ray. In industry the disease is often dis Amosite pipe covering weighs about 14 pounds ;lon distillation of samples abling, but it is much less frequent than silicosis, per cubic foot, with a temperature limit of 7J0*F. ` r determining the indices with which it very properly is classed. as compared to magnesia wiLh a weight of 16 /elyn Peake and Mrs. It was not felt that experience in a single yard pounds per cubic foot, and a temperature limit of ed with the experiments, was enough to justify any general statements on 00* F. High temperature amosite pipe covering -ried out studies of pigment working conditions in other yards, and certainly weighs about 18 pounds per cubic foot as compared eels, as indicated above. was no cause for alarm, but the results warranted to 26 pounds per cubic foot for other high temper check-ups elsewhere. Accordingly, arrangements ature insulations. Because 0: the lower con were made to examine by chest X-ray the pipe ductivity and the higher temperature limit of rr nodieeauen of Perls's cavercm in two Government Navy Yards, A and sideria in tissues. Aren. 5, and in two Navy Contract Yards, C and D. ~\ Examinations were made of the working conditions is. L. L.: Supersatur- including dust counts of the air breathed with the amosite type, less of it need be used In a com bination covering than other types 0: insulations. The development of amosite felt juried ix 1934 when a need existed to secure a thermal es in dilute isopropanol microscopic and chemical analysis of the dust -ute fatty degeneration itself. `:mitimer technique. Arch. We would point out that this procedure is ~<3. customary in making such surveys of occupational mir.itjon of volatile halo- diseases--medical examination of the workers -.m in blood. Tkis J., ZS: and a study of the nature and concentration of insulation lighter in weight and thermally mere effie'en: than the materials (blocks ar.c crmer.t cr asbestos blankets) which were then being used on destroyer turbines. The-Xavy approved the type developed by a manufacturer in September, 1934. Originally amosite was used only for - v.-- -- ihe ohvsiological the contaminants in the air .breathed. lorethyiene. Tins Jn r*., Pitz Covering Material turbine insulation, but it proved so satisfactory that its field of application enlarged to in clue; insulation of valves, fittings, Sangts. etc. From Macixjlv, D. C A-vn CcN-j An important ingredient of pipe covering comparison of the tncctyj materia! used on U. S. Navy vessels is arnosite. oride and triciioretbylece.j This mineral is a magnesium iron silicate of .938. variable composition. The name is the generic the initial destroyer, it has been used on almost all the destroyers bufit since that time ana on all other combat vessels bufit since before the War. a. P. A, rzxam, T. I-J one for an asbestos type of fibrous mineral mined A-vn PoarrarmLO, V. i-n South Airia. :.:-d!cKlorothace (etayleno The chief reasons for the wide use of amosite Its acute toricty and the? a5cr.11. S3. 1943. J. Pharmacol, i! j * Received for publication Sentenaoer 21. 1945. Published by permission of the U. S. Navy. The opin ions and assertions contained herein are the private ones T, H. T., Jjl, A.VD CaWT-VlTJ. f the writers, and are not to be eonscrced as ofijdal or sic torrity of carbon tetri- 'eieming the views of the Navy Department or the epesurea 936. and field studies! -J sival service at large. 1 Comdr. SIC, USN'R. Asst. Chief Health * Lieut. KfSl USXR, Health Consultant. Consultant P.i The halogtsaied hydro^ 'Lieut. H(S) USNR. Health Consultant. mcity ind potential dangenl . 'Chior Health Consultant, U. S. Maritime Commis 937. sion. Pipe covering was a later development in late 1935 and early 1936. Due to the manufacturing problems involved, it took a longer time to evolve into a satisfactory shape, and its first use cn naval vessels was in 1937. Since that time its use has spread markedly and it was used on the great majority of naval combat vessels bu2t curing World War IL Water-repellent amosite felt was developed during the early part of 1942, as a replacement for hair felt in the ir.suiatioo of cold water lines to prevent sweating. Hair felt had the riisatl- 9 srsyrr?1 "Lyre." z. exhibit ho-------- I 10 JOURNAL OF INDUSTRIAL EYGIENE AND TOXICOLOGY l*o^. 22, iw.; i 7Wd] vuu;e of being combustible and ax it was organic, when it became wet it moulded or rotted and could harbor vermin. At this time fires on board certain naval vessels convinced the Navy of the desirability of eliminating any combustible material from on board ship. .Eventually water* repellent amosite was made in strips of 50 foot lengths and of suitable width to enclose the circumference of the pipe and enclosed in an extremely light-weight muslin to fadilute hand ling and reduce the dust, which the water-re pellent agent accentuated. L DrsocrnoN or Otejutions and Woxetnc ENvuormmrT Asbestosis- results from breathing asbestos fibers of relatively long length, such as 15 to 75 micoas. It is not caused by breathing chopped up asbestos fibers of one or two microns (1). Therefore we are concerned with the presence in air of asbestos fibers which can be seen as such under low power of the ordinary microscope. The clinical picture of asbestosis can easily be complicated by the presence of diatomiceous earth, a iota of amorphous silica, which can cause sulmsis and is probably a more serious health risk than asbestosis. Another dust which may be present is magnesia, MgO, which is in very common use as a heat insulator and is harmless. Therefore our analyses were done to indicate . fcovr much fibrous type of asbestos dust was present in the air breathed, how much silica was present (especially as diatomaeeous earth), and how much oi the harmless ingredients like iron oxide and carbonates. Pipe covering may be divided into seven dinerent operations as follows: 1. Laying out and cutting 2. Band lev cutting J. 5Vnj and freparation of beets and jackets 4. Cement mixing 5. ifelding 6. Grinding 7. Installation an beard imp !. Layin i aid end cutting Rolls of the insulating felt are unwrapped and unrolled on a large layout table or on the Soor of the shop. This material, with the exception of the type known as water repellent amosite, is then well wetted with a fine water spray. It is marked into measured sections and cut with a rotary electric hand saw. The cut sections are rolled up and either used immediately or stacked in the storeroom. Usually one to three workers are employed at this operation. During the handling, unwrapping and unrolling of the asbestos, considerable oust arises, but appears to settle readily. A very fin: water spray should be used for wetting down the material ax a high velocity spray stirs up dust. Once it is wetted the handling and cutting of the material causes little visible dust. All of the four yards surveyed wet down the insulating material described above. ' One Navy Yard has an elaborate exhaust system for the layout table. The entire top of this tabic is covered with small periorations through which the air is exhausted. This table is sumeieatlv large that no more than two-thirds of the top is ever covered with material and room air is thereby exhausted through the other third. While ne velocity or .capacity measurements were mace on this system, data presented later in the report indicate that this control measure had a marked enect in reducing the dust count. 2. Bend seat culling A standard band saw such, as is found b wood working shops is used to cat insulation blocks an: boards bto desired shapes. This operatio: Ter protects, hr insulation m-ith cement e asbestos fibers, nf water is acd: thorougrly ag: {mill amounts a pail with a tr when the asce: string trough mixing. Qtdisz separate room r The dustiness c e! exhaust' vex or both, allhou; Petrographic eicate that the -ay be as high : 5. ifelding Molding is the tion to fit odd sh iorm is made to insulated. Bloc sections giued t with asbestos cat with asbestos Insulation can to be Installed usually cone produces large amounts of air-borne dust, most of which settles slowly. Normally there is only one worker on this operation at any one-time. Inasmuch as this is a very custy operation, operation. Very operation and no protection is req- 6. Griming the band saw should be enclosed in a room by Several shipya itself and should be equipped with adequate loo! prefabricated set exhaust ventilation both above and below the uo this material saw table. Because of the mechanical dimcultie* cement, all o b locating this exhaust properly, some of the dustiness. Norm dust will escape bto the air and the operator shoul: euent btervals . therefore wear an approved dust respirator. frposed, but the 3. Seeing and preparation of boett and jacket rer.eral room ex> In this operation jacket covers for valves arc rr.-pimtor worn b pipe joints are fabricated. The work consists o: Iretaliation cuttbg asbestos doth with shears, paddiag'ib Tncre are a at jackets with bsulxtbg material, and sewbg will ',*>!< covering oa wire or. asbestos cord. These operations givi 'rapped and pou rise to only slight amounts of visible dust, anc and joints and :a exhaust ventilation ar.d respiratory protectio: or asbestos card, are neither required nor used. There is usuaU; with prefabrimt; a large number of workers doing this operatio: see hand scvl in one large room. r.i:it-d cement is : 4. Cement miring a smoother finish fl>"N *?' CO LOGY [at. it, m. ; Jon. mil PIPE COVERJDfG OPERATION'S 11 '<d sections and cut with For protection and to give a neat appearance /. The cut'sections are i the insulation on board ship is usually covered immediately or sucked j with cement containing a high percentage of asbestos fibers. In mixing, the proper amount .irre workers are employed at j of water is added to the dry asbestos cement and ring the handling, unwrapping J thoroughly agitated with a hoe. Occasionally asbestos, considerable dust j small amounts of asbestos cement are mixed in i lettle readily. A very fine | a paQ with a trowel. Considerable dust is raised be used for wetting down the i when the asbestos cement is dumped into the velocity Py UP dust- 1 nixing trough and during the early stages of : handling and catting of the < mixing. Ordinarily this process is done in a ,.,e visible dust. _ All of the j separate room and only one operator is exposed. cd wet down the insulating ` The dustiness of this operation warrants the use hove. i of exhaust ventfiation or respiratory protection a an elaborate exhaust system or both, although neither is generally used. ^ The entire top of this uble Petrographic analyses of asbestos cement in -11 perforations through which'} dicate that the amount of diatomaceous earth i. This table is sumciently | cay be as high as 87 per cent by count. . than two-thL'ds of the top is j 5. Moldint naterial and room sir is thereby Molding is the process of building up the insula the other third. While no tion to fit odd shapes of boilerwork and piping. A y measurements were made fora is made to the exact shape of the part to be :a presented later in the report insulated. Slock insulation is laid on, adjoining' roatroi measure had a marked sections glued together, exposed surfaces sealed se dust count! with asbestos cement and the whole mold covered -r with asbestos cloth. When dry, the molded i saw such as is found in wood- insulation can be lifted o the form and is ready *o cut insulation blocks and to be installed on board ship. This operation is shapes. This operation usually done in the shop next to the sewing nounis of air-borne dust, most operation. Very little dust is produced from this .lowiy. Normally there is only operation and no special ventilation or respiratory operation at any one time. protection is required. -Is is a very dusty operation,! 6. Grinding odd be enclosed in a roam by[ Several shipyards reclaim their scrap pieces of e equipped with adequate local- prefabricated sections of insulation by grinding n both above and below thej up this materia! and, using it in the asbestos use of the mechanical cimcdtiesi cement, all of which contributes considerable eahaust properly, some of thej dustiness. Normally this job is done at infre o the air and the operator shouldl quent intervals and only one or two men are approved dust respirator. i exposed, but the operation should be isolated, prefcrcJion ef beds and jcciciS' general room exhaust supplied and an approved 'o jacket covers for valves and: respirator worn by the operator. nricated. The work. Consists of 7. ImScUaiion ef pipe entering on board tkip cloth with shears, padding the There are a number of operations involved in u-itmg material, and sewing with pipe covering on board ship. Insulation felt is t=rd. Toese operations give: wrapped and pounded tightly around large pipes *t amounts of visible dust, ancj and joints and fastened firmly in place with wire non and respiratory *proteciiob or asbestos cord. Pipes and boilers are covered red nor used. There is usually! with prefabricated sections, which necessitates of workers doing this opemtiorj tome hand sewing to fit the sections. Ready nixed cement is applied to fill in spaces and give rinZ a smoother finish. Some insulation is wrapped with glass doth or asbestos doth for greater strength. The only operations that product much dust are the wrapping and pouncing o: snosite and the sewing of sections. Nearly all of the compartments on board ship arc involved in this work, although most of it is aoncentrated in the machinery spaces. Usually the greater number of pipe eoverers work on board ship and relatively few men in the shop. The spacing of workers ranges from one or two men doing a small job in a living space to as many as twenty or thirty men working on ter. or more jobs in the engine room. Temporary exhaust ventilation is seldom used on board ship lor pipe covering and very few of the workers wear respir ators. Because of the varied nature of pipe covering operations in ship compartments, genera: exhaust ventilation is to be preferred. If the compartment is large, such as the main engine room, five air changes per hour are r.etced. In small com partments, such as living spaces, ten to fifteen air changes per hour are required. IL Coitposimos or Matziuacs Ussm According to Navy Specification the rovir.rs of asbestos insulating felt (amosite) shall contain not less than 95 per cent asbestes fiber cf the following composition: SUiei (SIOi) per cent minimum.............................. 47.5 Iron oxide (Fe;Oi) per cent maximum.................... 45.0 Magnesium oxide (MgO) per eer.t minimum......... 6.0 Typical analysis of the two types of asbestos fibers in general use are tabulated below: CkrjtttiU ^*wri u Silica (SiOO................ ....... 59.05To......... .. 50.74% hligccsia CMgO)........ ....... 40.07%......... .. 5.96% ....... 5.67%......... Ferric oxide (Fe;O0__ ....... | 2.41%.......... .. 7.SO% Ferrous oxide (FcO)... .. 52.00% Sodium oxice (N*1tO).. .. 2.12% Combined water (N*iO) ....... 14.45%......... .. 5.00% Therefore amosite alone will no: ccreply with Nav>' Specifications because of the low rr.scr.ssia content and must be mixed with chrysotvle asbestos to equal or exceed the 6.0 per cent mininun value for magnesia. On the other hand, chrysotile cannot be used alone because o: its siira content which is below the minimum 47.5 per cent specified by the Navy. The r.vo types 12 JOURNAL OF INDUSTRIAL HYGIENE AND TOXICOLOGY fwf. ZZ, w. j i ef asbestos fibers must be mixed together in the ard sewing were done with a small amount el rr.Lsing were cone at proper proportions to satisfy the values set /or space (or storage. Cross draft ventilation was respirators were ec magnesia and silica. The amounts of these provided by open windows on both sides of thr procedures. At the materials used to form this mixture there/ore room. fabrication of boots would be 6--(3 per cent chrysotile asbestos and Work on board ship was not supplied with carried out. A srr.aL 94-57 per cent amosite asbestos. exhaust ventilation. was cone c= board ta These two fibers differ mainly in their physical No asbestos workers were found wearing res Material was cut characteristics. Chrysotile is capable of being pirators. room and One opera readily separated into very fine fibers with a so/t U, S. Zfavy Yard. B. respirator, int dust silky (eel, whereas amosite is harsher and requires There were 50 men working in the shop and 703 'through slat under more manipulation to fiberize it. One authority men on board ship. The shop was divided inte a part o! the dust gi' has stated' that the chrysotile has the finest in four main rooms: Layout, Sewing, Cement, and There was r.o ear.: dividual fibers, and amosite the coarsest. Be Storage and Band saw combined. With the other than for the t TABLE I Scwaxv or Mattxiais Usrn at Exes Yaxb nx Morcnr pipe covering operatic wails anc ratters oi frequent ir.ier.'als * VAVT TAU A VAYT TiXS 1 comjfrnu c eemixr * cleaner. Most pipe applied in the ever.: Amosite 58,200 sq. ft. 50.000 sq. ft. 40,000 sq. ft. 6,325 sq. ft. Cortrcd Yard D. Tr.ere were 8 mec Amosite (water-repellent) Prefabricated sections (molded and block) -- 15,000 sq. ft. 600 sq. ft. 1,200 sq.ft. 59,900 linear ft. 115,000 linear ft. -- 1,750 sq. ft. 18.500 linear ft. 3,300 sq. ft. 15,700 linear ft- working on board ski were cct is she and jackets fc: pipe fabricated and surp: Asbestos doth 76,500 sq. ft. 106,600 sq. ft. 34,700 sq. ft. 40,000 sq. ft. smaller shop the op and cutting c: Metaffie twine .Asbestos yam -- 1501b. -- -- and fire felt. Tr.ere in either shop cor for on board skip. All ^ Asbestos paper -- 5,500 sq. ft. 4,003 sq. ft. 5.500 sq. ft. in a compartment on . who wore an appro' Asbestos board 2,700 linear ft. 6,000 sq. ft. 150 sq. ft. ---- mao who cur the .Asbestos cement 34,400 1b. ; 15,000 Ih. 57,500 lb. 38,500 lb. was r.o bir.c saw cuv IV. Anatyszs or f muse of this difference we may suspect a deeded decrease in the number of respirable fibers (below 200 microns in length and 5 microns in diameter) whenever amosite is used in preference to chrysotile asbestos. IH. ?n>E Covrzpec Facimrs at IsmrrarAi. Shtfya&ds 17.5. .Vary Yard A. There were 84 men working in the shop and 467 men on board ship. The shop was divided into two rooms, one of which was primarily for storage and occasional grinding and band saw cutting operations. The only mechanical exhaust ventilation in the shop was provided for the grind ing, mixing and band saw cutting operations and was inadequate. In the other room layout, cutting Cc exception of the Cement Room, the doors betwer these were normally left open. There are r.o estah The work in the Sewing Room consisted most) or safe dustiness i= of fabricating and sewing valve boots and jacket Urccsscn et a!. (2) tr. All the cement used on board ship was mixed i the asbestos textile : the Cement Room. There was no exhaust ve jurtidcs of total dus: tilation for either the Sewing or Cement Roox lur that industry. V The band saw was equipped with a flexible exhau- that the asbestos sex rube above the table and an exhaust around tl ir.g industries differ w blade below the saw table. The layout tab' In textile plants w. was equipped with exhaust ventilation as descrior ?|wcinc jobs with fa: above. There was no exhaust ventilation supp'ik lur ume years, wbe on board ship for pipe covering and no workr r-imtc between shop were found wearing respirators. luruc ship campartes Contract Yard C. in >Iu,t exposure. There were 51 men working ia the shop and 31 In cor.sras: so tr on board ship. Layout, cutting and cerot: cnvcrcr's materials c k. A.1* 2C,Y PIPE COVERING OPERATIONS 13 * small amount of-' mixing were done at one end of the shop. Dust alt ventilation was respirators were occasionally worn during these n on both sides of the t: procedures. At the other end of the shop the 1 fabrication of boots, jackets and molds were 3 was not supplied with earned out. A small amount of such fabrication was done on board ship. rcre found wearing res Material was cut with a band saw in a separate room and the operator wore an approved dust respirator. The dust from this saw was exhausted ting in the shop and 7001 through a slot under the table which caught only shop was divided into! a part of the dust given off above the table. ut. Sewing, Cement, indi There was no exhaust ventilation in the shop, combined. With Che 1 other than for the band saw, and none for the pipe covering operations on board ship. All doors, walls and Tafters of the shop were cleaned at frequent intervals with an industrial vacuum deaaer. Most pipe covering on board ship was tc COUTlACr Ttu applied in the evening during the second shift. ft. 6.323 sq. /L CorJrud Yard D. There were 8 men in the shop and 160 men 3,300 sq. ft. working on board ship. Pipe covering operations were done in two shops. In the main one, boots /* - It. 15.700 linear ft and jackets for pipe valves and connections were fabricated and surplus material stored. -In the smaller shop the operations consisted of layout ft-. 40,000 sq. it. and cutting of amosite, water repellent amosite j- and fire felt. There was no exhaust ventilation in either shop nor for the pipe covering operation on board ship. All the asbestos cement was mixed 5.500 sq. fL in a compartment on board ship. The only worker who wore an approved dust respirator was the -- man who cut the two types of amosite. There was no band saw cutting of asbestos in this yard. { 38.500 lh. IV. Anjutses or Settled "Dost a.vd Dust Cocxts , Room, the doors betwee: There are no established figures for permissible P- or safe dustiness in pipe covering operations. Rocn consisted mostly - Naive boots and jacketsi Dreessen et aL (2) in their study of asbestosis in the asbestos textile industry suggested 5 million Nurd ship was mixed i: re was no exhaust vex -c-wing or Cement Roots particles of total dust by irspinger as a threshold for that industry. IVe ^ould lil-e to Point out tt-f .1.. vhMtw textile and asbestos pipe cover- wd vith a flexible exhaus j^gjndustries diner widely in tnetr oust tataua an exhaust srousd ti la textug plants workers usually contingent ble. Tee layout tab! specific jobs wita tamy constant dust exposures :t ventilation as describe ILL--wncress me pipe coverer may "lust ventilation supplie rotate between shop and ship and irom str.ail_tP overing and no worite: atom. large sh|g_ compartments with a wide variation in.dusiernosure. . i-*; vn the shop and 121 - cutting and cemeq covcrcr's rr.atfnals diner mtfcrdlv in xhtir -is- bestos content, ranging from 85 per ;-- --a-- (10-1S5> asbestos) to amosite asbes-.esl. When lsbestos- ctments_o;ntiin large amounts of dtatomaceous earth there is a resultant iillcssis harard as inciatcd lbovc. In general .wC jKHhat dust ceu.ntr bclnw-l jlSlifla-Paaides per cubic foot by Kontmerer l-A-mro vood dust enntyoL Our figures in Table 2 were determined by the Konimeter and not with the impinger instrument. We used the Xonimeter bemuse it 'is light, easily portable and takes records which can be kept indefinitely. As is indicated in Table 3. the dustiest operations are band saw cutting, cement mixing, and installation on board ship. V. Medical Fcmcccs The incidence of asbestosis among pipe coverers as determined by chest X-ray Is given in Table 4. The relation between years of exposure and per' cent asbestosis is included in Table 3. Due to frequent turnover of shipyard workers and the length of time required to X-ray a large numbef of workers, the number X-rayed may r.ot equal the number of pipe coverers. At Contract Yard C X-rays were examined of men who hsc left the yard while at Navy Yard a few pipe coverers were not X-rayed. At Navy Yard A the 48 X-rayed out of 531 were all older men working in the shop. __ Some of these pipe coverers had had pre-shipyard experience in the asbestos industry, but the uties are based solely on shipyard exposure. At Contract Yard C, for example, the Asbestos Scop estimated that about one-third of their pipe coverers had worked with asbestos before coming to the yard. The one ease of advanced asbestosis at Contract Yard C had worked in the asbestos industry for 23 years before coming to work in the yard. At Contract Yard D the two cases of moderate asbestosis had worked 22 years and 30 years at pipe covering in their yard. All of the X-ray films used in the above exu 'vert first read by roentgenologists of the Medial Department of the yard and then by one of tie authors (W. E. F.). Dr. W. C. Dreessen. U. S. P. H. S., was kind enough to examine the three positive plates and *ae agreed 00 the diagnosis. Since only three workers out of the 1074 X-rayed had asbestosis, and each of the three bad beea a pipe coverer for more than 20 years, it wouid itn !!. w:ervy:--yTT.i * TABLE 2 Axalysej or Stmiu Durr axu Aa S*io*u^ 4 artXATiax % It S rti ezrr List mir IQ tfQAH! ar ccen l! m *WxwmM. Xea u **zi*.* 5xz | m m u JZ z a 44 C 2. M c --V m* It ,-|i S* '"*wc 5s #fijtfsf2*. i5|31 5 E i 1 bott eervn (JllfOT Tul dust ASBESTOS BCIT m avr AiltTTVI Xmuar*il( A**T t JUsn f AvtJctau n Layout and cutting Navy Yard A....................... 95 16 6 12 6 24 26 10 2 3.5- 8.7 6.1 0.21-0.5010.35 S.7- 6.0 Navy Yard B....................... 92 10 8 12 tr 40 18 12 / 1.6- 6.5 4.210.01-0.54;0.23:0.6- 7.9 Contract Yard C................. 95 30 5 10 tr 26 14 15 4 17.1- 22.2l20.5ll.I3--4.30!2.1S!6.6-19.5 Contract Yard D................. 95 26 6 8 tr 29 21 10 5 6.3- 16.3 10.9:0.09-1.1610.6311.4i ii 8.7 Cutting with band saw Navy Yard A...................... Navy Yard B........-............. Contract Yard C................. 98 98 97 9 63 8 tr 2 tr 2 ll.O- 19.2 15.1:0.10-0.14:0.12:0.:- 0.9 48 16 12 2 132.4- 46.6139.5 2.8- 3.2 J.O 6.5- 8.7 10 4 12 3 18.2-100-}- 73+ .9-12.8 6.29j4.3-12.5 J4*. ir-Vj Cci Lavout and cutting... Hand saw mu:;........ and fabricaliot Crrnent miring............. Gnndirg........................ General room................ She? avenge............ Stis avenge....... AVer MPPC~ - Molding operations Contract Yard C................. 98 Contract Yard D................. 95 8 66 3 tr 7 6 10 4 9 I tr 48 10 12 J.vcacxc or Arst: Scttlsj & pre?. boots 8c jackets Navy Yard A....................... Navy Yard B (Sewing as- bentos cloth) (StuSng with anosite)... Contract Yard C................. Contract Y'ard D................. 98 98 95 98 Storeroom Contract Yard D................. 95 12 tr 9 tr 8 8 11 tr 26 6 11 3 6 6 8 tr 15 2 7 tr . 2 3.S-. 6.1 4.6 .01- .06 0.03 0.3 -1.0 42 21 16 3 3.3- 6.0 6.810.0- 9.4 0.1 0. -6.4 38 20 15 1 2.1- .2.1 0 .0.3 0 22 12 14 2 10.6- 12.3 11.4 .45- .79 .6213.7 -7.4 38 28 14 5 3.9- 10.9 6.0J0. - .05 .0ol0. -0.5 26 32 12 Navy Y'ard A.......... Navy Yard 3.......... Cvr.trac: Yard C..., Cosine: Yard D.., 4CtiU. Cement mining Navy Yard A....................... Navy Yard B....................... Contract Yard C................. Contract Yard D (on board ship).................................. 16 5.4- 30+ 31 + 0. -0.52:0.2 Or-- 0.7 2 67. -100+ 84+ 1.6 -1.7 1.7 1.4- 2.5 2 33.8- 48.7 41.3 1.6 -4.7 3.1 4.7-10.0 kin-u.s'ssu? 2cm-s. I.NC3CX; 5 19.6- 40.0 32 0. - .02 .01 0. - .02: Grinding scrap materials Navy Yard A....................... 88 8 20 16 1 10 33 12115 9.4-100+ 50+ 0. -1.6 .47-0. -2.6 General rooa Navy Yard A....................... Navy Yard B....................... Contract Yard C.................. Contract Yard D................. Aboard ship Navy Yard A....................... Navy Y'ard B....................... Contract Y'ard C.................. Contract Y'ard D................. 49 0.2- 24.6 10.0 0; -1.4 O.CS .02-0.3 1.6- 3.3 2.4:0. - .01 .01 0. -0.6 4 0.0- 21.6114.210.34-1.7 .8 |3.S -7.9 5 3.9- 10.9 6.0:0. 1 - .OS 1 .02:1 0. -O.j i 30 65. -250. 142 io. -o.i:;o.o2:o. -o.c 15 84.4-192.0 12s li.36-5.::;:.21 1.1 -3.7 15 25.3- 89.0149.2"0.23-2.5811.10,0.5 -6.1 15 8.0- 22.ljll.0j0. -0.21j0.03j0. -1.0 * ,\'ote: MPPCF -- Million particles of dust per cubic foot of air. Navy Yard A Expos Aficc'.r ?freer. ( Errov Niw Vard 'J Allee:r I Perce.*. C !a:T. C--.Lra.-i Yard lr [E= l Yard D <a:: l Ter 14 \ u*. pipe covering operations 15 ^c?>rcD*. TABLE 3 Coktazbok or Ln--NTH or Vaxiooj OrmaTtoss Of Eacx Sctvyajlb iOft 1 Rtcnt sf Atfiim J-- lruJ ' R |tuwniu[ IAvctI 4| s.j!o.:s-o.so;o.:sIs.7- 6.o ;.::o.ai-o.54io.23.`o.6- :.9 J.i!l.I3--1.3o!2.I3j6.6eI9.5 3.9.'0.09-I. IfiIlo.S,Il.4-= S.7 I i.:!o.10-0.14:0.12:0.7- 0.9 9.5:2.8- 3.2 13.0 !d.S- 8.7 :-rj 8 6.19U.3-12.S *nr tau a KLrT TAM > nmue: uu c COK*TAtCT 74JL9 * Tout Cut Atfemv** (Hit Tatal dut Atboitt eui TuJ dust AikniM Attii ''I duuj Jjj-out and cutting..................... llud uw cutting....................... Swing and fabrication............... Crmtnt miziog............................ Grinding..................................... (Vcorral room.............................. utter* 6.1 13.1 4.8 31.0 50.0 10.0 0.33 0.12 0.03 0.2 0.47 0.08 utter 4.2 0.23 39.5 3.0 4.8 0.1 84.0 1.7 --* 2.4 0.01 utter 20.5 2.18 73.0 6.19 11.4 0.62 41.3 3.1 -- 14.2 0.8 utter 10.9 0.63 -- 6.0 0.03 37.C 0.01 -- 6.C o.o: \ Shop average........................... 30.0 0.23 26.9 1.0 . 32.0 2.6 Ship avenge............................ 142.0 0.02 128.0 2.8 49.2 1.1 7.6 C.73 11.0 C .03 .Vote: MPPCP -- Million particies of dust per cubic foot of air. TABLE 4 lsaEfa or Asarsrosis Akovc Per Covcxru ..6? .Cl- .0610.03:0.5 -1.0 ! 6 "V 9.4 [o.l 0. -6.4 10.30. -- .79 .62.3.7 -T.-i /. - .03 .0310. -0.5 IOTU& I t nn j | mitt or um j Of ASautosu ru ULY0 ML&j* Mao* Ad* BJki r> u ruck 551 48 0' o Navy Yini B.......... 750 662 0 0 Coauuct Yard C.... 174 196 0 Contract Yard D... 168 168 0 0 1 o 0 1 0 Totals................... 1683 1074 0 2 1 -!o. -0.52:0.2 ;o. - o. -rjl.6 -1.7 1.7 1.4- 2.3 511.6 -4.7 |j.l 4.7-10.0 l. - .07! .Cl!10. - .001 TABLE 3 Rmjtrtoxssny Bmvrr.v Lrxcra or Exwstmx un Ikc3l.vc or Assrsrcsis SS7TAX9 txajl* tx rot gyrruNC uocntr 0-1 -1.6 | .4710. -2.6 { ;I i .0 0: -1.4 '0.CS' .07-0.5 ! ic. - ,c:. .010. -O.t' .:o.i4-u: I .s !3.i -7.*! ,0c. - ,c3'. .CO'O. -C.51 -----------------1------ '------ :----- : !; ! : o. -C. 1:10.07.0* --0.C*, * 1.36-1. ii.i -5.7j 3'l.100.3 -6.51 0 0. _ :::o.o3c. t [Eunosec............ Navy Yard A j Ahmed............ 1/*2 la j i a 0 0 |o 0 erc: OTci C7c| OTc i oo1 p?_. -- f , ah ic: r* Navy Yard B j.ASemcd............j 0 j0 10 (rerersufr____ CSc> 0\c fErpovea.../ o iici i ::: -e=t-ic-- Vard C \ A5ectec___ | o | o i o ! : ^Ptreentage..! 07e! 0%i 0%; Te yI Exposed..., 20 : 111 : 3 1 9 ' e=smet Vara L ASectm___ 0 [Pereeauet.: 0%: ora:- appear that asbestos pipe covering c.r naval vessels is a relatively sale occupation. However, : -- -a: be remembered that these men rotated an erg the various operations of pipe covering and ve;E set esntinually exposed to high car.cer.t.-aiicas c: asbestos dust as found da hand sa-- cutur.r and exment miring. The suggestions mid: relative to exhaust ventilation and respiratory protection are therefore of value in maintaining this low incidence of asbestcus. Dbcpssion The exTrrmeiy low incidence c: asbestesis found, 0.29 per cent, or 3 cases out ot 1C74 pipcovertrs, stands in marbed ca a urns: to tee high dust concentration found in several cf the pipe covering operations. As shown in Table 2. the total dust concentration for band sat.- cutting ranged from 13.1 to *3.0 .-r.L'ion partides per cubic feet, for cement mining from 31.0 to 34.0. and for Installation on board ship, from 11.0 :c 142.0. The solution o: this apparent discrepancy lies in a characteristic peculiar tc the pipe mversr.r trace, that is lack of a necessity ter soeciaiiaatiea. la general, pipe ccvtrrn are capable "c: cciar all cl the operation; describee abo---j. --a m: varuer may be ernnged irem or.t cperaticr. to anetr.er c: to ciuerect job; in tar same type c: without less c: eniaier.ry ana aaanrhiar tc tar ci=inds or ******* cor**'**^!***. I* ** apparent that a pipe coverec's environment may change every few days or lew weeks a: the mest with a constant .-.uctuartrr. in the cut: eaaear.tr.tior. which he branthat. Thererort. tor hr urea giver, in Table 3 ior shop average arc shm average cannot give a comae;itr meturr o: to: arrester t A. _16- - - - \~jCXTxkxL OF INDUSTRIAL HYGIENE AND TOXICOLOGY [wol.ZZ, m*.l among these workers would have been considerably .thatit worker mayinsuhe ever a. period of years. It is further apparent that to obtain such zxpcsusis'jc ^ ^aure. da.3y_dust_counts at eachipcrifle job "-iniarii ship compartment and inThe shop together -with.'the time 'spent on -each job -would have to '.be oropSed "separately for each worker. In this VI. CosciDSioxi [ ' "i i rprrt asbestos .pipe ^covering differs markedly L The 'chartcler -of -ahi.tcw .pipe .covering fronT'the asbestos textile'industry where .dust industry on board naval vessels is -such that concentrations for an operation do not fluctuate . ^conclusions drawn from other asbestos industries widely and where iwrefkertrill usually remain-at such as textiles, cannot be applied. a spedne job for some yean. 2. The operations of band saw catting, grinding, 'A further iaaor in maintaining a low incidence cement snoring, and installation on board ship of asbestosis is that in band saw cutting, grinding, and cement mixing only one or two men are in* wived and the*work is usually done at infrequent should be equipped with exhaust ventuation to keep the total dust concentration low. 3. The inodesce of asbestosis among pipe intervals ruck as several times a week. Finally, pipe enverers also apply glass wool, reck wool, magnesia, and other types of non* asbestos insulation, all of which decreases the covens in the shipyards studied was low, 0 29 per cent or 3 eases out of 1074. In view of the nature of shipyard pipe covering work, this low incidence amount of exposure to asbestos dust. It seems likely to us that if the pipe eaverers studied had worked steacuy at any of the above operations * where the amount of asbestos dust in the air was censistently high, the incidence of asbestosis is not surprising. 4. Since each of the 3 caves of asbestosis had worked at asbestos pipe covering in shipyards fer more than 20 years, it may be conduced that sum pipe covering is sot a-dangerous occupation. J/rti*n tf Jnattx/rieJ AM Ac * I cJ. tea procue a plates upon cooling.--^ prevalent on decks or surfaces art iSeceed. measures include shrink: application of beat, erdin-' dame, to a distorted sectic or accompanied by a ; Shrinking is often net: mrrus or coained spaces: the ejperttica may cat nraiures art in use. An recently provided an cepshrir.ke: developing ryec vf nitrogen pciscrirr whit 10 days later from rtpor. REFERENCES Tr.rtt other vetiters al - r"- Lotna, A. ]: Silicosis and asbestosis. Osord University Press. New York, New York, 1932. G> Dxsxssrx, Vi'. C is the asbestos e: ah: A study of asbestosis textile industry. Bulk No. (3) Faery, J. C: Ships and aircraft of the united States Frees. 2nd War Zd-tic: u 1944. Publishrrf by Ships and Aircraft, I 163 Broadway, New York, New York. rrpssure experienced a ecu symptoms, but were ap fvllott-ing day. The purpose cf this invc 241, Public Health Service, U. S. Treasury the exposures which ari Department, 1932. .vmail, unventilated enmpa , Orrsu The torch ordinarily 1 the conventional oxyac In most instances the tc annular ring attacimen *Kith supplies a couiLt. hi water around the nan hition of the torch, conct m-1 piste can be restored A- with cryacttyient wt _-rof the torch tip is cet: vf netcl encountered. \ O.rinJ on thir. steel the ti: ranee eummeniy used b cn; Jtity of the shrinking * Vrccivn] tor evbiistic 1 iD.luitrial Hvgtent Ee; t \ Ul- i-T"