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1 &QW88 I OFFICE COPY Biochemical Research Laboratory The Bow Chemical Company A/O O EXPOSURE TO PINE BUSTS ENCOUNTERED BY WORKERS CUTTING VARIOUS TYPES OP PIPE COVERING MATERIAL Pile: T2.1-3-1 Bate: July 21, 1965 By: E. J. Schneider Bate V/u./tS Bate 7- PROBLEM A question was raised by shop personnel after reading an article of the health hazards associated with exposure to asbestos. Is there a health hazard from asbestos in cutting various types of pipe covering material used at Bow Corning? The Environmental Research Laboratory was asked to evaluate the exposures to the fine dusts encountered by workers cutting the pipe covering materia and to determine the possible health hazard. CONCLUSIONS 1. Concentrations of total dust in excess of acceptable levels can be encountered by workers cutting pipe covering material both by hand and in using a table saw. 2. A total dust count or the number of particles per million cubic feet of air also exceeds acceptable levels at times. 3. The amount of asbestos fibers of significant length found within the dust exceeds 25 per cent of the fiber content, RESTRICTED: for use within The Dow Chemical Company only. Biochemical Research Laboratory T2.1-3-1 Page 2 however, fibers constitute only 10 per cent of the total t dust* The possibility that Dow Corning workers are being exposed to excessive amounts of asbestos fibers within the important fiber lengths (20-50 microns) is unlikely, however, it is advisable and prudent to have workers wear respiratory protection while cutting pipe covering material. This is especially true when using a table saw. 4. Mo one type of pipe covering material was found to have a significantly greater amount of asbestos fibers than the others. The Phillip Carey Flbercel material does produce considerable more fine dust than the others when cut. ASBESTOS In reviewing the literature^^ it is learned that the most common form of asbestos. is known as chrysotlle, a hydrous magnesium silicate containing from 12.5 to 14 per cent water of crystallization* There is another form of asbestos derived from amphlbole which occurs as a variety of minerals consisting of iron, calcium and magnesium silicates with little water of con stitution. This latter type of asbestos consists of shorter fibers but is more stable chemically than chrysotlle and more resistant to acids and heat. U) Industrial Toxicology - L* T. Fairhall, pp. 19-21, 1957 Biochemical Research Laboratory T2.1-3-1 Page 3 /S iU U U U D u It is this latter type of asbestos which is thought to be used in the various pipe covering material tested because x-ray diffraction analysis of the materials showed them to con tain tobermorlte, a calcium silicate form of asbestos. The inhalation of asbestos dust produces a condition known as asbestosis. Asbestos is the only silicate apart from talc and mica which does not contain free silica and yet produces pulmonary lung flbrotlc changes. The fibrogenlc action differs from silica in that the effects are produced only' by long asbestos fibers. Very short fibers appear to have little or no effect. The long fibers apparently block the finer bronchioles of the lungs and produce flbrotlc changes as a result of irritation* The literature^) states that in the case of asbestosis unlike silicosis fibrosis does not progress indefinitely after cessation of exposure. It further states that In order to produce asbestosis in workers exposures must be in excess of 5 millions particles cubic foot for extended periods (greater than 10 years) and the fibers in the range of 10-250 p In length. Some authorities indicated that only those asbestos fibers in the 20-50 y range are significant for producing asbestosis. The present Industrial Hygiene Standards state that for control the number of particles of asbestos dust be kept be Low j yj * 'Industrial Hygiene and Toxicology - Frank pp. mwggfrxgsgr--------------------- tatty, Vol. I, Biochemical hesearch Laboratory 72.1-3-1 rage 4 5 mpcf and that for nualance duets of any type the number of particles must be below 50 mpcf or 15 mgs total dust per cubic fOOt Ol* ,ii.. PRESENTATION OK DATA Kai-ij *.j x96p a visit was made to Dow Corning to make measurement* :-i .nc dust exposures encountered by workers cutting pipe covering . lal. In a small room (approximately 10* x iV) adjacent to tin i.u-ocnter shop building 409 a worker was asked to hand saw sever. '*-ces of the various types of pipe covering material used at Dow Corning* Air samples were collected in his breathing zone while sawing the materials* Analyses were made for both total ou-. ana the number of particles of dust in the contaminated air In another .;..uil roan (approximately 8* x 6') part of tne pipe shop building 316 tests were repeated for two different pipe covering materiaw wuile a worker used a table saw to cut tne materials* At both . *^ns only general ventilation was usee with no local exhaust for dust collection* The air samples collected for total du3t louo w*re iv.cr sent to Dow laboratories for x-ny diffraction analysis :*ru: i:;n microscopic evaluation. Table 1 snows a summary of the results obtained fur the air samples by the various analytical technique* `able [ ;x?t: ?i*a rvsrs aKccvvrsssp sy crrrrr vamous types cr pipe cdvesino xmaiAts Industrial Standard, `lulsanee Dusts , . . . 15 me/e} I,i4.i;rUi H?tJoe S:an4in). Flbtri , , . 5 H.P.C.P. I fTitli 2_: Electron microscope J 1 ; gxo-.jj-e] -v-' " _J1 .st Itunt* **.?*'. X-snv Diffraction Ana tv*1* Analysis) Particie Site (Piter IX cr 7c tal rust'- Piter Fire |"rttr Inj t:re cf verier hand isi.lnr ri;d*:r Fr.ret Hill iCrl.- b; .:i* curved 2" iiilM j 4*1 sire o.5 0.09 Aw?. }2 C.4 *.3 Ji.o 12.6 1*^5 Tcbertsorite 35* (o.5-1.5) cao . S!0, . (o.5-2-0) v 95* Tcbe rewrite (0.3-1.5) CaO . SIP, . (0.5-2.0) *>5.< 33* <10 p <23 M <10 p <20 li <13 u 5* \% <23 u >53 u a* 5v 4** <13 p <2: a %=; c 25* 45 ! tut <).:!! -*-enj-rar.ilrt} Jteylo ifltt t; :c.: 2* thi:.: 11 3.60 A v* # J7.3 22.2 1?,3 Tcberswrite *5* (0.3-1.5) c*e . S10,, . (0.5-2.0) H-0 90% * <10 p <23 U * * <:o p 7;- <"2 M >53 u t -'Mtl ji.ir.r PhiliIn Carey tercel urvcJ black 2* :.*Jck 1 1 !';n: uiilr,; Fhlllln l-sro;1 ijl ;*.l c.r . id ilnc.: 2" thlr* 1 17.90 t VtJ* 7.25 7.9 12.1 lj. 0 11.0 Toberr.orlte *55 (0.8-1.5) Ca0 . S10- . (0.5-2.0) H.n vOt * <10 u <20 u 3^C0j . ItgOHjj 3V ~y* <10 u ?5< <23 U s-t <13 u <22 p >53 P *.+ <13 M <73 u "** * >52 u -5* 25* "w! u.lr.r ?i|61n FF.rt: Hill nlseat!* r:it bloc/. 2" thick -.3? 13.5 TslCTorlte 35* <13 m (0.3-1.5) CaO . S10a . (0.5-2.0) HjO 95* <20 p 5-1 a1 <*97* <13 M <23 u >33 u -5* - r* i . -1 n - of uilnj j :o cut "i.tiU'Ttrnlnj flat bin;.: 2" thick 77.93 Tabemorlte *5* <10 U (?.;-!.5) ClO . SIC, . (0.5-2.3)H-0 92* <20 ij i <13 p 2<? <23 p r3< >52 U H 'lift- table *ju to cut 2a Id.. In Enre: :>',! i ''ntbestca flat block 53-93 5l.i Toberaorlte 35* (j.3-1.5) caO . S10- . (0.5-2.0) V 35* <13 M <23 u : <13 p 5? <20 P 70t >53 p 25* 1 7/cnrmn i <; Biochemical Research Laboratory TJ>, 1-3-1 Page 6 The total duet exposure la not excessive in hand sawing most;of the types of pipe covering material, however, sawing the Phillip Carey Fibercel material does produce a very fine dust and does produce excessive concentrations of dust. The use of the table saw as would be expected produces very large quantities of dust even for a not too dusty material such as the Baldwin Ehret Hill Unibestos. The dust count in millions of particles per cubic foot did exceed In all cases the 5 mpcf Industrial Hygiene Standard for asbestos. However, because asbestos fibers represent approxi mately 10?t of the total dust and because only approximately 25$ of the fibers are considered of significant size, it is doubtful that workers encounter a health hazard in their normal work load of cutting pipe covering material. The practice of using a table saw either within a shop building or out in the field should not be continued without adequate control of the dust or the use of respiratory devices. It also seems advisable to encourage workers to wear respiratory protection when hand sawing material. Anv Bureau of Standards approved dust respirator should prove aiequate to filter out the asbestos fibers. ST0000573 Biochemical Research Laboratory Ti, 1-5*1 Page 7 UNIT INDEX Measurements were made of the dust exposures encountered by workers cutting pipe covering material* Pipe Shop Department, Dow Coming Corporation, Midland, Michigan, Concentrations of total dust in excess of acceptable levels can be produced both in hand sawing and in the use of a table saw. The amount of asbestos fibers found did not constitute a health hazard. Respiratory protection i3 recommended tc be worn when cutting pipe covering material. DISTRIBUTION Jack Quinn, Safety Department, Dow Corning Corporation H. H. Gay, M.D., Medical Department, 607 Building A. W. Wilson, Safety Department, 401 Building C. Middleton, Safety Department, Ludlngton Division W. Snodgrass, Maint. Service Admin., 49 Building (7/9/71) (4) t r> f l rt rt ft TO. E. J. Schneider THE DOW CHEMICAL COMPANY |UP* KEI*E DAT! 20 Kay 1965 A L wmii m S 57-9** 5 analytical laboratories REPORT .-- ouacc 700-1***00-003 NOIkli HYDRATED CALCIUM .".ILICATE ON LATEX FILTERS K1CR0SC0FY Particle size determinatlor About 65# About 900 0 < 10 u < 20 u > 50 u Filters 1,5, 6, About 85% < 10 .. About 95# < 20 u Filters 2. 3. **. 7 About **5# About 90% < 10 u < 20 u Fiber size determination About 1$ About 10 1 About 65# < 10 u < 20 u > 50 u Filters 7 About 1% About 20 About 90 % < 10 u < 20 u > 50 u ? iKora 2,4,6 About 5# About 10 % < 10 u < 20 u About **5> 750 tt Filters 1,3,5,8 About 1% About 50 About 70 0 < 10 u <20 u > 50 u. Fibers would account for about 10 0 of the residue ins. 8 mv y R. laps bb 12 *** 20 J- UCHCO P. A. Traylor 2351 57H PHOTOMICROGRAPH* ALS 57-qaq Photomicrographs were prepared employing Bright field y Phase Contrast ________ Oblique Transmitted Light Dark field ___________ Polarized Light Oblique Reflected Light_ technlqu to show particles ani fibers Label Data for 8 x 10 prints contact prints Negative # L5-525 L5-526 Sample Latex Filter // 2 Latex Filter # 8 y Mieroscoov B. P. B. F. Magnif 300X 300X THI DOW CHEMICAL COMPANY CHEMICAL PHYSICS RESEARCH LASORATORY 168499 to >M>4ESMr RlLfHr*C Z. J. Schneider IWOJfCT Biochem Res, Lab. 1701 X-ray Diffraction Analysis of dust samples from cutting pipe covering at Dow Corning CM*(aO. 1219-26 wit IICIRIt 2-2-65 .ICalO H. rf. Rinn o*tr 2-11-65 ) #1 (.0001 C> Tobermorite - XCh0*Si03>yH30 where x varies between 0,6 and 1,5 and y between 0.5 and 2.0 2 (>.0001 g) Same as #1 #3 (.0004 g) Same as #1 #4 (.0020 g) Same as #1 05 (.0008 g) This sample ~ave a very weak pattern of hydromagnesite - 3HgC03Mg0H)3*3Ha0. There could be amorphous material present. #6 (<.0001 g) Tobermorite and some calcite. Pattern quite weak, probably because of small sample. 07 (.0052 g) Mainly tobermorite with 10-20% tialcite - CaC03. #8 (.0036 g) Mainly tobermorite with 5-10% calcite. No quartz was detected la any o the samples. Note on appearance of tobermorite - from Crystallographic Data for the Calcium Silicates by Heller and Taylor. Natural mineral from Ballycraigy: minute, radiating agregates of fibers with distinctive silky lustre on the cleavage faces. Natural mineral from Mull or Skye: fine geared aggregates of minute, birefringent crystals. Synthetic material: minute irregular crystals, birefringent. HWR:abJ 2-11-65 3 IMP II t..A Z.LS0QQQ1S &LSOOO 0.15 i ( c c c c c c r Tublf: r HXr*nm*E TO PXMR V'-V jtkped by v:o!rrCTn r~:~f Industrial Hyrtienc "tandarn, nuisances *.-s: Industrial Myijiene standard, Asbestcs -lb.* ooeration 'Total Duse Kxoosurej xn/m^ fDust **. ?.c.p. Breathing zone or worker hand sawing Baldwin Ehret Hill calcium silicate curved block 2" thick Repeat same material O.A5 0.09 3.2 6.4 <1.8 an.6 12.6 A vg. 14.5 Hand cawing Owene-Corning Kaylo flat block 2" thick 3*60 A vg. 17.3 22.2 19.3 Hand sawing Phillip Carey Flbercel curved block 2" thick 17.90 A vg. 7.9 12.1 10.0 Hand sawing Phillip Carey 8556 MAG curved block 2" thick 7.20 11.0 A-*?ay Diffract!- Tobcrxorito (o.S-1.5) cao . r,!f. Tobermorite (0.3-1,3) ca^ . r.irv Tobermorite (0.8-1.5) cao . r.i'r Tobermorite ,(0.8-1.5) Cao . jio? 3^00^ . Mg0H)g . 3- Hand sawing Baldwin Ehret Hill Unlbestos flat block 2" thick o.oy 13.5 Tobermorite (0.3-1.5) caO . SIC. Breathing zone of worker using table saw to cut Cwens-Corning Kaylo flat block 2" thick Using table saw to cut Baldwin Ehret Hill Unlbestos flat block 2" thick 77.90 53.90 1 -' -- 'T'------ Tobermorite (0.8-1.5) CaO . ;~,U 53.6 ' Tobermorite (o.ti-1.5) CaO . Sic. ,Jgjmpmimmmmqm I E'.S jS 'O O O O J.S tr-v. K3 VAPICT, lusts .... Ubers ... r ? rIrK-'tATKHIAT." 15 mr/m * 5 K.r.C.P. t... :tlon Ana i* la F.lectron Microscope Analysis ) Particle Size (Fibers 10* of Total Oust) Fiber Size 20-50 JJ io2 . Co.1;- 856 <10 P 95* <20 P 1* <10 p 5* <20 B TO* >50 p 25* 45* 102 . (0.5-2.0) h20 9056 <10 JJ <20 P 5? <10 p 10* <20 n 45* >50 p 45* 102 . (0.5- 2.0) h20 -- 4556 9056 <10 <20 u 1* <10 p 5* <20 p 70* >50 p 25* 0- . 45* 102 . (0.5- 2.0) H-0 90* <10 V <20 P 5* <10 p 10* <20 p 45* >50 p 45* 42 --- 3H20 .10- . (0.5-2.0) H-0 85)6 9556 85* 9556 <10 P <20 u <10 p <20 p ir0 . 310- . (0.3-2.0)13-0 4556 90* <10 p <20 u 310- . (0.5 2.0) H-0 1" 85* 95* <10 M <20 U 1* 5* 70* 5* 10* 45* 1* 2* 90*- 1* 5* 70* <10 p <20 p >50 li <10 p <20 p >50 P <10 p <20 p >50 u <10 p <20 (J >50 p 25* 45* 8* 25* wupaPEs; INDUSTRIAL HYGIENE SAMPLE RECORD SMPlMttalTNM burn uti SSMLftt Li.TZ/'-- ra./' 3' / p'Ltiih. aorMant ot oanei * i kk '/Ar Dew C^<vy^fe NTOMTIIUTTM U OUTUOf TWf, lUATKfDttACl iT*J. VtHtUTMi Bu* Y#< o>-rr~4-^uL' -- -r--< /*/r L-n.at^b- C^3/k -ri .>//.W,w ?>> Cu.^=i/7-------- $AMkC tOTYLl ocscmmoN timC ITAST IW COHCINT*ATIO 3/3/ -/ ``tMifl Bz U~/,..>_ B>/.-- CJLcntJt fj. c--i/Z7 2/3/ -2 5".------------32J . 2/3/ -3 2/3/ -* 2/3/ -r 0 ^* i (Tom^ r r~-- 1 OT W r ^ 77 |xrTri r~ /A& Cmv VfSi/tos. s-~- 2/3/ -C TtJttSL BX LJjmm. Qt>J /Vul 2rfsUJL r.~-l 2/3/ '7 Bl a--^ tstf. 3/1 "t t-X i-Mx /4JL .T^ 2/3/ 'f -)M*g U*M *MTU H I.U 12 3/l ^Lt3- new. u-*sc. a"/pr^e^. A-~bl--', * .I PtOILlM -rz. 3- / MOL. . l*TI CtPLAMATlONOP CALCULATION* CALCULATIONS RECORD UtllMk ttMLOMO .. cuAr-fe. CDNVIIMONHALOCtN TO TOTAL PIOCSU Dow C* CA//A/G &**/. OaTC '/''/Ar UuNLC 1 TMC 4/3/ */ /O/wi. mt p. 2-/3Z -3 r _ L 0L. ANALYSIS r*r<it. wr CONC. */* 243 Afc, o./<--*if_ 0 .o*/4" ///. r iA, < 0 '--i A .oo**? nt. s' o.ooit/ O.V-T-<yF /! 0?~y 3.C im -4 r/3/ 'r 4/3/ -t -- 4/3/ -7 4/3/ -S' r s--i. T-~ 3--. m. r .feL///. r -fc6///. rM. WU- U.S Ak. ?.0 A<T^. 0.0/7? O.? 0 0.0*7/* ^ <) 7 3t~~T. 0.077? 0. f3 7 /7.T--5 7 2 77. < ________ c rc C CJ o u iM#UM6*TN00 MtftmQ misum OrpMlTf* WTTVtt INDUSTRIAL HYGIENE SAMPLE RECORD M#bC At j >*014.M T2./-3-/' VTAMSTIt oa Mines m. OUTUM ?*. MUM TUT. In.be.' IMTC ! //ZV/CT wciu Ddu> CfCA*AO MATIHAL