Document QEoNMJYB1oYnZ4RBRrovDobk

* KLD "'V* Mr. 7*0. Pennington, J.. fiobert# Ud Asalgnaent Ho. Fhyaio* Sef. Work by Written "by Approved by Bate PEI 1010 - PH.1504. T.&. Wright M. XAaondjon * 1.6. Wright 3. Heines. 17tb Ootober, I960. 3PBJHCT in investigation of tbe Health Hmrt associated with the Linpet asbestos oeaest spray prooett. OBJECT fo neasure the else distribution end conoentration of airborne fast released during the application of Linpet asbestos oeaest* mSODOCTIOW Post neasureaeats on the Uspct SprayFibre process have been carried out in the paet.'&btf. 1) bat. la Tier of the attention foeneed on this problea aor^reoestly, uyte-dste laforaatlon la repaired to assist Is assessing ..the health risk. . Tbr the purpose of, Initiating- this eriqnirv, nesrarenests vere osrried oat/ah. j.V.Sobarts Ltd. (Bbrvieh; on an experimental scale and also<'on^slte. . She sites ehosen were the "Xepress of Canada" while on the' stocks- at} the Vioiare-Amatrong shipyard, lfewaastle--on-^ne, and, the new.Besearoh laboratories of Pllkiagtoa it this stage the eonelaslona snst of neeessity be of a tantatlro nature. Za soae of the tests it was only possible to oarxy out single neasureaeats and it is therefore impossible to estinate the aconracy of the results. Again, a saber of eo^arlsen tests were carried out la which replication waa possible bat, eitheegh the results yielded nesn values wfaioh were- la accordance with expectation, failed to achieve statistical algnlfloance* Zt is also neoessar^ to point eat that this enqoiry has evoked a saber of aajor issues. Tor instance, it is by ae aeans certain that the scwpllng equipaeet employed (the standard T.B.A* dost T--r^F opparatns i.e. the Caeella themal precipitator) was appropriate to the task. 1* Tbr 13.3, the airborne dust concentration assured la tbs spray booth at Bonrich was about 5000 particles per o.e. 2. Ter EW.25, the airborne dust concentration assured received in the spray booth at Harwich was 2,000 partlolea per o.e. 5* She dost concentrations neasored on board ship at Tickers* Anstrong shipyard ranged free roughly 6,000 particlea/o.o. (for da^ed LW.25) to 14,000 particles/o.c. (for undaeped 13.3). . 4. The estlaated dost concentrations for'CT.25 sprayed on the selected building site (at lethaa Park) ranged froa 140 particles/o.o. to 520 partlolea/o.o. for seven sasples with om further sasple yielding e value of 1,400 partiolea/o.e. Continued 025530 5. The affeot of atlas the flipping mechanise was- ttailed on board ship tod, although lover dust eoostt vere obtained, the apparent improvement vat not statistically significant. Furthermore the redootloa in dust level as measured was la any ease disappointing. 6. Satber surprisingly, dust measurements Bade at 7.V. Roberts Ltd. failed to reveal an isprevesent when m need. . 7. In the oase of bine fibre, danplng teens to have been largely effective in the yp 1m range and to tone extent In the 5m to 10m range. There ie also soae Indication that pre-damping efalto fibre has produoed a eoarser else grading due to the suppression of fines. .. * 6. Xxperlments carried- oat at Scrwiah suggest that, after spraying has oeased, the dost eontest of tho atsosphere in the spray area soon reaches e safe level. Zn the ease ef blue fibre a period of ton ninntes la probably sufficient - while an Interval of twenty sinutea should suffice for the white grade. . . 9. Results fTon tests carried eat sese years ago suggest that no difficulty Is involved in distinguishing between asbestos and oeeest particles when viewed under the aderosoope. (Ref. l) It can only be assuned that this vat carried out on an arbitrary basis because we have been so far unsuooessful. RBCCTOtSTOinCWS 1. 2. smatCT jU these testa hath east soso doubt upon the suitability of the thermal precipitator for raspling la atnospherea where the dust ecneentration is-changing rapidly, settlenest nethode *"** be,investigated before, pay further work is contemplated* Is an alternative the Bexhlet naan sampler sight be stodiei la mere detail. " This instrument has- aiready been used by 7.Y.R. Ltd. vith'mbme success, but for basis investigations the instrument wbbld. need to be calibrated for each quality ef spray fibre, to taka late aeeeunt differences la else distribu tion. .** aV.j.. \ Sanples ef airborne dust la the region of Unpet spray naohlaes have been obtained while operating at J.f. Roberta Ltd. and on alto. Two grades of spray fibre were considered (IS.3 and EY.25) and the effeet ef *aT<"ir and predanping has beon examined. Total eonoootrationa and also distributions have boon determined. OTPittan REPORT ` * The testa described here were oommaeeed on 25th February I960 and deal with the exanlnatien ef the dusty conditions la evldsnee during the Limpet spraying operation. Samples of the atmosphere were taken la the spray booth at J.W* Roberta Ltd. (Sonrich) and also on solsotod sites; arrangements vere made to take sasploa from the Impress ef Canada* prior to Isnuohlng and fron tho new Research laboratories being constructed at Lathaa FUrk for FUklagtoa Bros. Ltd. The sampling equipment need was that used in routine dost eurvuyj at Roobdalm sal Hiiriley Green vis; the Casells thermal precipitator. Sasploa were taken for two qualities of spray fibre, LB.3 and LT.25* without using the mechanise. Further samples were taken to assets the effeet ef dawplng and also to dieeover the offset of pre-dasped fibre. 1 test was esrrled out oa each quality to obtain some idea of the rate of sedimentation after spraying had ceased. Contisnqfc rs> cn cn Xaoh tuple nt Inclucreted tt 500C to remove* any ertraaeous earbonaoeons cotter present tad then exanlzued under the Yiekars Rejection Hloroscope used os * aonoeular aioroseope employing e dork ground reference with a 4 ca objective* By aeons of these eounts the sloe distribution of eeoh sample was determined and the dust concentration calculated* farther tests were eorried out in the laboratory in on atteapt to distlngnish between asbestos and oeaest portioles using a Polaroid system and phase contrast aethods. These were unsueeeea* fal. inother method, ?ii{ the stain dispersion technique, is being ixrestigatcd# ' CTTITTfl QT TESTS .` . Test fl) On 25th february, I960, firs ataospherie saaples were taken at J*. Roberts Ltd# (Borwioh) under the following conditions** ' . & (ill Spray dlreetad onto the wall# ' fire alnntea after completing operation (i) Spray dlreetad onto the celling* fire alsstes after eoapleting operation (ill) Spray directed onto tho wall using pre-daaped fibre* the fibre used was DT*25* On 27th Jpril.l9&0-twelve atmospheric saaples were token in duplicate on boari-the "Snprese of Canada** Six saaples were taken for blue fibre and six for white fibre.'-`tin each ease-half of>the aaaples were taken Titb.'-.thcydaaping aeohanisw inOperation and the rest Test (3) A series of'.sample*'we*-.|taken while spraying was being carried out ifrs/new btfifiUng ereeted at Imtham Park la the aemlng of l'0tb\luguafc,}36o* There was a strong air current passing throtg^r-thb' eprey area so two sables were taken ^stream of thityeperutor and two downstream} in each ease aeasureaenta were made in duplicate i*e* using two thermal precipitators* Test (U.) Zn the afternoon of 10th August I960, five aaaples were obtained at J.* Roberts Ltd# (Borwioh)* The programme was the sane as in Test (l) but, on this occasion, the fibre used was I*3* Test (5) ' Dapllsate else analyses were obtained ter a saaple of Portland eeaent taken from a bag which was in the Rochdale works* Coning and quartering was used to reduoe the bulk sample and petroleum jelly was used' as a dispersing agent# Ksauus Test 1 CT.gS at J..R. Ltd. ' Sis total eeaoestrationa and eo&eentrations in aaoh of tho stated sise ranges appear in Table X# Table XX is a sunary of the sise distributions whioh are also shown plotorially la figure 1 It can be seen that pre-damping appears to have little or no effect on the total dust concentration nor on the else distribution of the airborne dost# Test 2 Samples from the *Bwnress of Canada*. The results of these tests appear in Tables 3 A 4 in figure 2. Saaples 1*3 and 7*9 were taJan with the dating mechanism in use. Samples and 1(^12 were taken with the damping mechanism out of motion* Proa Table 3 the following results have been calculated* Continued 025532 Cowpariaon of blue and While fibre Nmb concentration obtained for blue fibre 11,600 * 1,100 p/eo.* Kean eoaoestratios obtained for white fibre 9,100 * 1,600 p/oo. Student's* t-test was applied to the difference between theee------ n and the diffaresoe m found to be signifioent at the l^C level. Effect of Pawpln* ' Sean concentration observed for damped fibre (both grade*) 9,700 - 1,300 p/oo. Seta concentration observed for undamped fibre (both grides) ^ 11,000 - 1,700 p/ce. The difference between the 'two Man* obtaiaed here would be expected to oeeur about ones in ten ooeaeions as a result of pure ehaaoe where aa real difference elated, there is, therefore, only a slight indication that dawping has been effective In rednoisg the dnst level* % Considering the two grades of fibre separately the following results were obtained t- - fhlte fibre Mean concentration obtained for damped white fibre 8,400 - 1,000 p/oow Kean concentration obtained. 2b*undamped white fibre 9,700 3,500 p/oo. The differenoe between these aeaa values would be ezpeeted to occur ea alaost one in five eooaslons where no real differenoe exists and Bust therefore be considered to be not signified^* Blue fibre *^ * * * t% ^ Kean eonoentratlon observed for deleft* bln* fibre 11,000 - 2,100 p/oe. Kean eonoentratlon observed for undamped blue fibre 12,200 - 1,400 p/oo. The differenoe ohtsined oould he expe'eted tie, oeeur on one out ef aiae eooaslons ss a result of randoe flnetuatibia and is therefore aoaroely significant. .* Site distribution . Significance tests were slso carried out grade by grade and have been taken into aeoonnt in the eonolusions. Test 3 Sawaies frew Lathan Part The results obtaiaed froa these tests appear in Tahlas 3 d 6. The else distributions appearing in Table 6 have been plotted In figure 3* Saeples 142 were taken upstream of-the operator and sawples 3 A 4 downstream ef the operator. Zt eaa he seen free Table 6 and figure 3 that there epnears to be ao real differenoe between the saeples taken upstreaa froa those taken downstream with respect to also distribution, fro* tbs point ef view of total dust oonoentration, there again appears to be good agreement 1a each direction if the value of 1,437*9 p/eo. is discounted. There la good reeson for believing that this particular sample was contaminated. 025533 The ooaoentrations quoted in this eeetion have been rounded off to the nearest 100 p/co. The limits shown are confidenoe limita and have been quoted to serve as an Indication of accuracy* the tte*t has - been performed separately and does not involve theee limits. Continued fait A Saaples taken for LB.1 at J.T.B. Ltd. ' The results obtained appear la Tables ? A 8 atkl else distributions are depleted la figure 4* Tests 1-4 The results of tbese testa are stumarlsed la figure 5. Test S Slse aaalrsia of Poytlan^ dmmmnt * The emulative else distributions obtalaed for the tee sub-aeaplas considered are sheen ia Sable $ together with a seen also distribution* In each ease at least 625 partioles^were counted la order to give a random ooustlag error of - 29Cg the aagoitade of the other errors involved la not kasa TTSCTOSIOIf CT BBULT3 She results obtained to date aust be regarded with soae reserve- tioa In general, it would appear that too few saaples were taken. At Jfevoastle, however, twelve saaples were taken la dnplisate (l.e. ualag two sailing units) and, even so, it is difficult to pronounce judgesent -on the results. Zt was disappointing to find that ia. these*-testa the two stapling units used shoved differences la .the neasurdaenfe of dust oonoeBtratioas, Unfortunately, thik was not expected beforehand, and, consequently, the figures obtained are subjeot to aa extrtf source of variation. * . r. . Saualin* Method *''?/'.* -*,..*/, % V, ^ , . * ^ the sampling instrument usbd/hesfotiat acceptance far reutlae . durt surveys but say set be ultabi* Spc this purpose. It is quite possible that, aa a result'of ped&satatioa of particles during the tests, the *oocoentrationi'-'ataas\xUd are over^atlaatea of the true values. w<4y lathan Park Saaples # The aise diatrlbutlona obtained for these saaples are act la agreeeent with other saaples obtalaed for Lt.25. It is quite possible that the larger particles were aeoepted by the precipita tor because of their high settling rates whereas the ssallcr particles were swept away by the air current present. ) Reference J. f. Heberts Ltd. * 'Limpet* Asbestos Spray Vaehlses by 3, S. Areas 17th March I960. 025534 rrBmyjj. MM I Measured Concentration of l^rhai-ne Post in Partlclea/aa cVt*4**d for Uf.23 it I.T.B. Ltd. ' Saapla Be. Score* . i-lw l-2n 1 Spray rat* vail '. 1466*0 623*2 2 5 iaa. after aaapl* X 1150*1 179.2 3 Spray oste colling 1476*2 287*6 V 5 aiaa* after saxpl* 3 350*3 179*9 5 Spray onto vail (prc Jcvpod) 1195*4 360,5 . Sis* Basgea | 2-5u 5-lOu L0-20u >20u total \ 551*8 56.7 U7,2 89;7 208.3 99.4 6*3 43.2 25.0 43.4 26.0 -- 31*2 14*4 46.8 2576.6! 10.2 2*9 1395.2 7.2 1972*e 24*9 1314*2 43.4 1897*5 ?v Sin Piatribtttl*^ ff idrbonie Pftwt - Perevntage fry '*- ** atJ.T.a^Ltd. Vv " . . 7# Saapl* ?u. Swore* 1 Spray onto vail 2 5 alaa. aftar aaapla 1 3 Spray onto coiling 4 5 adaa. after *a*pl* 3 5 Spray onto vail (pra-daapad) ^ C/ !*** /V Sis* Stages 4-lti v* 56.7 82*3 74.8 75*4 62.9 '</ 24*3 12*9 14*6 13.7 19*0 - 2-Ji 13.7 4*1 7.4 6*8 11.0 5-10p 10-2CU >20u 3.9 2-0 0*4 0.5 0.2 2.2 0.6 0*4 1.9 1.1 1*1 2.3 2.5 2*3 On 9k W4 f* 0 Mt r w * ** PS S W 8* **. (BON NO N S Vm VI aw O On H fI tf rfOni ' 9v r oo \m ro IS o ro oo h o 5 9\'o as a* ONM ga la 09 H M O 03 8$ VMN* MM S3 i*ui gg <0 ny* T 23 KS bo 33 o VM C 03 Cm CO s VMNJI V* tO ? V* *- *S w<g v/i to ii SJI ON * 3to Jo KS to S m 90 H VN NO SS.8 o r ro f? VJI tt C * & f1*0 V <t Ya o o ft s** ? VJt ft & to o c 5 13 B 0 **? Se fip Ov* ^ to,- " Vm H O IN3 W NT O OB rr o V s n^r .Kg'; PCT NHM NO *vo O 83 U si) K Vm .. is> O' 0-Sfl 'iji- ^E , K *0 j \ b' . ** 0%\0 PS OS--J \-j4k \M> CD-J NOVI ^Stf VOS" -ON * 0- V ov` 03 \f> na* ON to bo se ij 10' a ON w to wo g . to OO' b BS c o*w OWN ** ir H w o T s g w 8 0VK B* V* H U ON sa V&SO M VO -o o oO ** NJi o MO t On o*10l to NO T to c 5s VM M ** 10M4 VJNV* 9k9 2s M ON H* wta 4 V* V* VM CO S? N o\w #--J ON SO tBifiO*n ow Vm ro to O o on OH* +- ON o 90 VtNO vovn ON to Up to VvMi VO-n ON gg 3 ro -M4 M9CsIVM S to NON H- f 8* Y V a f<t o % ft c o ?8 o s PP NM *U to CD -o UN Vo* sk On CD 4u*i M NO <23-4 y S itt i. % no cn cn co S* %$ 5? NO -4 _M \n VlO* C*N CO CD U EABLS IT Saeplet froa the *Emtret of Cspads* Slta Plttrlbutlonx ef Airborne Put Peroentsire Br Wimbar. Blue JLbe*td* Ceaeut Seattle Slse Besses tfuabex *1*1 1-2 H 2-5 p 5-10 M 10-2 . hlte Aibestoi Staple Slse JUnras - >20(x rfuaber *"*U 1*2 *i 2-fc 5-iq* : x 55*8 23.2 17.0 3.1 0*6 0.3 58.9 21*9 12.3 4.2 2*0 0.7 7 91.2 7.2 1*3 0.1 0.1 91.0 7.9 0*8 0.2 52.9 28*9 14*8 ,, 4.4. 0.8 0.2 e 89.3 8.2 UK 0.7 0.2 2 95*9 19.2 15.3 5.9 1.6 1.0 88.8 6.2 2.8 1.3 0.4 3 48*5 26,1 17.9 51-7 20*1 17.0 4.6 7.6 0.7 2.7 0.2 0.9 7 90.2 5.5 2.9 0.8 0.4 85.5 8.3 3.9 0.8 0.5 57*3 22*2 15.1 3.8 1.0 0.6 V 58*9 23.9 11.4 3.4 UK 1.0 87.2 9.5 2.3 0.6 0.3 89.1 6.9 2.4 0.6 0.3 53*2 22.2 18.4 2.7 0.1 , 5 58*8 25.8 10.7 2.8 2.2 ` 0.7 93.8 4.9 3.8 0.3 0.1 90.4 6.5 U4 0.9 0.5 c 50.9 21.5 13.9 2.0 :*.o / 0.7 ` * * / 3.5 0.7 0.2 0.1 57*5 25.4 12*9 2.9 - 0-.4% a W.4f 7.3 U1 0.6 0.1 r' <* 'r*S . -u'V "'i? <s j o ro cn cn go Ttble V iatta (if 25) Staples froa lethsa Ptrir Mostured Copocotratlon of Airborne Duet In Particles /oo Staple Ttiaber 3i*e 2*n*et 1-2 p 2-5n 5-1% 10-2Q* >20 M *ot*l 130.$ 396.0 57.6 36.0 75.8 26.0 16.8 1.0 11.0 - 28.3 0.6 320.1 522.8 9 75.5 25.1 35.0 2.1 1.9 * 3.8 111.0 141.1 73.0 61.1 16.7 5.3 15.1 318.2 128.$ i?;3 37.8 6.6 1.2 7.9 232.6 ? U00.1 ai.o 67.2 11.8 11*8 29.7 L137.9 161.8 77.8 18.0 23.0 1.8 23.0* 338.1 222.7 71.1 86.1 32.6 13.1 19.0 175.2 Ttble TI laosiie (IT m) Staples Itthsfc Part Site Distribution* of Airborne'-Putt - Fomenttge br fluaber . Staple <> * * Site Rtnaea ' V?* Suaber i-lu 1-2 IT'. 2-5 u 5-10 u 10>20u >20u 10.8 75.7 52.1 15.1 18.0 X 23.7 ; 5.51 3.1 18.1 *+< .8> v.^4: . 17.7 21.3 ' vsl .3 22.9. 19.3 5.S&7 1.7 8.6 0.2 2.6 1.8 3 55*3 20.3 16.3 2.9 1.8 3.1 76.5 11.7 1.7 1.0 1.0 2.1 1 17.6 23.0 16.8 15.0 11.2 6.8 16.2 S.3 1.1 6.8 3.8 10.3 j 025538 fable m . lb.i at r.w.n Lta. Featured Concentration of Airborne Ihit in Fartlclae/ aa. Staple Tuaber *-lu >2u Site Stage* 2-5 u 5-10 u 0-20a >20,, ! Total * 1. Spray onto wall. L395.7 1425.9 1548.4 491.4 412.9 587.2 5659.5 2. 5 aln* after aa^le 1. 305.2 25*.2 214.0 91.8 59.2 78.0 1007.2 3. Spray onto roof L333.8 1222.7 1587.0 589.3 122.0 255.9 5090.7 4. 5 alat.after ea^le 3. 550.4 388.4 522.9 135.2 78.8 79.9 1733.4 5. Spray onto tail (predaaped) L821.7 1731*8' 1727.5 615.8 424.8 44.2 6735.8 Table TUT * L.B.S at J.W.fc. ltd. . Site Pjrtribotlon'of Airborne Ppt - P&mentaee br Wuaber * Staple Rubber Source W - , t < . 4 . 'i ..3itfr*feanges f-lp '* !W` /*-5u 5-10(i 1. Spray onto vail 24.7 25.2 ` 'SSb$ 8.7 2. 5 alat after staple 1 30.3 25.7 9.1 3. Spray oato roof 26.2 24.0 30.8 11.6 4. 5 alat after staple 3 31.7 21.3 30.2 7.8 5. Spray onto vail (predaaped) 27.1 25.7 25.6 9.1 10-20(i >20(i 7.3 6.8 5.9 7.7 2.4 5.0 4.4 4.6 *, 6.3 6.2 ' Tti U The results of there tests are taaearised la Figure 5* .) i O ro cn cn co CD  Tiblg g 3ls Aaalnlt of Portland Cgent I I jC by Ko. < Statsd 81m Um Cn> 3uVt*apl x Sob-fttspl* 2 Uea ieilTils ' i 58.6* %.s 14.4 81.6 : \ 74.1 5 <' % 96*9 *% >$2.4 10 A cV'99.3. ' ' 9%7 2<Kj$ ." 99.7 r '. 99*4>, i;;ioo.o- .* .* wfcfl/ ^ *1. * , % V4 5U3 77.9 94.7 98.5 99.6 100.0 :` ji i ii 025540 TT 1 3 .3. 3 *-v ; ?\ o* ro cn cn. jr rsa TS TOWS > *<st e ?T . * ro cn cn Jr CO t s gS 3 om art*; pams > *; 4l #o?t &s ro cn cn  wlss '