Document yrm3RnBRKXE00zBrG8qeyB6gD

FILE NAME: Sprayed Asbestos (SPRA) DATE: 1971 DOC#: SPRA028 DOCUMENT DESCRIPTION: Medical Journal Article - Buildings Insulated with Sprayed Asbetos-A Potential Hazard , W>' 14. on 2r *' Pert^urnp - '971 Prirtc1, h Great Britain W IL D IN G S INSULATED WITH SPRAYED ASBESTOS: A POTENIIAL HAZARD K. P. S L u m i f y *, P. G . H arries* and F.-J. O ' K elly Medical Research Unu, HV1 Dockyard, De\onpoit and lleal'i) Oltice, Royal Nasal Hospital, Has'ar, Gospoit, Hants <Reccin'J 10 March 1971) * M istract-'-ln a survey of stoiehotises insulated with sprayed crocidolne and amosite asbestos t ic insulation was found to be damaged because a was unprotected Dust sam pling <ests O u ii.M Mia! the occupants of these storehouses could be exposed to Inum ful levels ot asbestos dust if t1e 'tisiilanon or fallen asbestos debus was disitubed. It is suggested lh a l this hazard rna; be w ' r o i L d by sealing the insuh'bon and piowd.mg means of piotecting the sealed "ist.'aiion acains! damagi IN L K O D U C T I O N Tin p h i \ " ! \ u : of asbestos-related disease in Dcvonport Dockyard is about 4 per cent oi t!ic population ( S h e e r s and T r m p l it o n , "468) and a dt:s' samplinn -.uney by M v<Ri!:S il 9'70) has shov n that high asbestos dust concentrations have occurred in slops ret! fn g m this Dockyard. A large proportion of met: wmk in the ships at o *time i >another and it -s reasonable to suppose that they may have been exposed io asbestos dust. Some of the highest asbestos dust concentrations have been I'onu 1dur ing the remov a! o:' sprayed crocidolite ' blue) asbesio , Exposure to this form of asbesio., is assoc.ale 1 with die development or mesotheha! tumours, rinrty-tivc Dockyatd employees m know" n have died fiom mesoihe''oma of/lie pleura between 196-1 r Strict mediations h ' e been introduced to protect the workers from funhei exposure io uarmfu! levels of asbestos dust (H a r r u s , 1968, 1971). A survey of possible hea,fh bazar .s due to asbestos has included the investigation of stor-G v iw tnsula'eJ with sprayed asbestos and the purpose of this pc wr is to draw auemdm to a potentially ha/tr hvus-situti'oon. Imuhiuou o' 'durehmtsc\ Stoieh. 'Os roofed whh corrugated metal or asbestos cement require insulation, and many such buildings attached to Nava! Dockyards have been msidmcd with xpt '-yed ash- tos whic1 has been applied to the undersides of the roofing and, in some cases, to *. , upper parts of me wads. Crocidolite and ante.site asbestos eve been \ " used and t'o- exposed ."-face, which is friable and easily damaged, has been 'eld unprotected. Damage has been caused by knocks from boxes stacked near the walls, s"'.!!' seoions of the in-ulmon D u e fallen off due to local patches of dampness, .. t an unexpected amount >n damage has been caused by birds who have been remo\ - bug the *sbestos for nesting material As a iesu't ol this activ:ty a large amount of a-oeslos d.mi-'s has fallen onto ledges, the tops of boxes, and iNj floor, flic extent to which d -s has occurred is shown in T ig. 1. * 2SS fpt S? K . P. S U'MirY. P G Harrii s and F. J. O 'K m v Disturbance of the insulation or the fallen asbestos debris ^ likely to cause air borne asbestos dust, and dust sampling tests have been made to assess the asbestos dust concentrations likely to occur in these storehouses. RESULTS Dust samples were collected on millipore membrane fillers, diameter 25 mm pore size 0.8 /im using DrLiger hand pumps. The samples were evaluated using the method described by H o lm es (1965). Asbestos dust concentrations in a group o f storehouses insulated with sprayed erocidolite are shown in Table 1. The lowest mean asbestos dust concentration was obtained in storehouses in which there was hardly any activity, a higher mean con centration was obtained where there was much activity, and the highest mean con centration occurred when fallen erocidolite debris wuis being disturbed. Some 50 people were engaged in packing foodstuffs and handling stores in those storehouses . with higher dust concentrations. The results o f sampling in a storehouse insulated with sprayed amosite are shown in Table 2. The results show a similar increase in asbestos dust concentration with activity, and that very high local dust concentrations may be expected when un protected sprayed asbestos is brushed against. Dust sampling was done in a storehouse in which part o f one wall had been in sulated with sprayed erocidolite. The asbestos had been sealed whh cement and paint but the sealant was old and cracked. A erocidolite dust concentration o f 25 fibuw cm ' was obtained when the floor below this insulation was cleaned with a brush. C O N CLU SIO N S The dust sampling results show that the concentrations of erocidolite and amosite rfl~.\.i) d-isi which may occur when unsealed sprayed insulation or fallen asbestos debris is disturbed are likely to be in excess of the* threshold levels suggested by H M Factory Inspectorate (1969). This is especially so in the case of erocidolite for which the biresh- old level is 02 ftbres/cm3. In a previous survey of buildings incorporating asbestos bv B y r o m et al. (1969) it was concluded that there was no hazard to the health of the occupants o f completed buildings. Although some buildings in that survey were, reported to be insulated with sprayed asbestos it was not stated whether or not this type of insulation was protected against damage. From the present survey it is concluded that sprayed asbestos insulation, especially erocidolite, is a potential hazard to the health o f the occupants of the buildings if the insulation is unprotected against damage. Sealing the insulation will control the hazard provided that the sealant is maintained in good condition. The fact that people who work m such buildings are beingexposed to asbestos may be overlooked when taking an occupational history. A . The Ministry o f Defence has decided to seal the sprayed asbestos insulation in storehouses in which there is a potential asbestos dust hazard and to provide means of protecting the sealed insulating from damage. Buildings insulated with sprayed asbestos a potential hazard F m*i 1. S iori iiot'sis i\'stu a h u w n it ('R (in i)oi m a s b i sios Activity in stores during sampling No. of samples Hardly any activity y A lot of activity (approx. 50 8 employees handling stotes) Disturbing fallen asbestos on 16 boxes oi the floor Asbestos dust concentration in librcsjcm1(crocidolite) Range Mean 001-1-26 0 03-10-31 0-3--52-6 0 26 . 2-76 ' 11-89 T able 2. Storehouses insulated WITH AMOSITf ASBESTOS Activity in stores during sampling N o. of samples Asbestos dust concentration in tibres/cmJ (amosite) Range Mean No activity 3 1-7-2-0 1-9 'S 4 8- 7-6 6-2 Mov tng boxes Brushing cement facing 1 3 75 oveilying sprayed asbestos Brushing unprotected spiayed 1 3S0 asbestos 4ckrodedgcn,cous-\\'e wish to thank the Photography Departments and the dust sampling sections of H\1 Dockyards at Devonport and Portsmouth for taking the photograph and lor earning ou the dust samp'mg We ate also giatdul to the Medical Director General tNtnal) tot pet mission u publish this report REFERENCES Byrom I C ., Hodgson, A . A . and Holmfs, S. (1969) Ann. occup. Hyg. 12, 141. Dr PARTS,rNT Of EMPLOYMENT AND PRODUCTIVITY. HM FACroRY INSEF-CrORATE (1969) Technical Data Note 13 Standardsjor Asbestos Dust Concentrations jar Use With the Asbestos Rittulutto.is 1969. H M S O , London Harrits, P. G . (1968) Ann occup. H sg. H , 135. Harries, P. G . (.1971) Ann. occup H yg.. 14, (3) 24! . Holmes, S. (1965) Ann. S Y Acad. Set. 132, 288. Sh h r s , Ci and T ru r m -o s, A R 11968) fir med .1 3,574