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WRG C0074G 75l3ft Application of Sprayed Inorganic Fiber Containing Asbestos: Occupational Health Hazards 1 PLAINTIFF'S i EXHIBIT J WRG-653 WILLIAM B. REITZE,* WILLIAM J. NICHOLSON', DUNCAN A. I-IOLADAY, and IRVING J. SELIKOFF Mount Sinai School of Medicine of the City University of New York, Fifth Avenue end 100th Street, New York, New York 10029 /c-3 Over 40,000 to ns of inorganic fibrous insulation containing asbestos were used in 1970 vSV by the construction industry as a fireproofing material in the erection of muiii-loried buildings. The application of this material by a spraying technique produces serious cartantination of the working environment. Asbestos fiber concentrations may ranee from 3`J f cc to more than ICO f/cc. Some early observations of the exposures and health of the workmen in this comparatively new occupation are given with photographs of the working areas. Nearby workers may be indirectly exposed. Such concentrations were found to be 70 I cc len feet from the spraying and 46 f/cc seventy-five feet away. Control measures are dis cussed. Introduction /">. ccupational hazards associated with the Vj' iiili.'.iatiun of asbestos fibers have been well established, with important risk ofasbestosis, bronchogenic carcinoma, mesothelioma (pleural and peritoneal), and possibly other neoplasms.1 Such hazarJs have been found in factories manufacturing asbestos products,2'4 i:: m.iics and mills producing the fiber,5'6 and in ilie use of asbestos products for insulation v.i.ik in the construction industry.7 Starling i:i 1066. we undertook an investiga: mi of another commercial use of asbe-uos in 'inch an occupation hazard <remcd possibleif. y::i\ i;of rvp..ra! fiber insulatiun material io- tircivooiing and heat insulation. Sprayed ir organic llbsr insulation was introi'... 1 in ii>32 with the Limpet process, by the ! Roberts Company of Great Britain. Mr. N. ` i* w .:iMi-.*&: Johna-MunviHe InJunnus, Man* >' 'uV Jcfsc>. store, s*.<u|iprrtc: in ojft by I'ubhc Health '* Grjnt hS-no.lSb ind t> Holt); Hootcu < NVi` Grunt IM 272. L. Dolbey. Director of Research for tins com pany, is usually acknowledged as the pioneer developer. British Railway coach makers used the sprayed product containing asbestos in their coaches to control condensation and noise- i: also acted as a thermal insulating material. In 1935 the spray process was first used in the United States. Most of the material applied dur ing the Isle 1930`s was used for decorative fin ishes in night clubs, restaurants, hotels, etc. When this material was four.3 also to be use ful as a fireproofing agent, such use gradually increased, and in 1950 the National Gypsum Company obtained the Underwriters Lai.orator ies' approval of its brand of spray ir.iuLfion for fireproofing. In early 1951 the Arbesicspray Company als. had an inorganic fiber blend tested til'd approved by llie L;. Jena:iters Lab oratories. The firs! use of sr *avej `mineral fibei" as a fireproofing -gem ;n a la'ge multi* stoic building oeeuned in j'>55 with the erec tion of the sixty-story Chase .`'-r.hjnvc. Hen!; l>,..l,lii.c in New Yini: City, it; id'u. well over half oi all the iaige muitisiory bi-fid.i its con- 176 i . this comiie pioneer .:er. used :os in their i noise; it .jU-riiil. In ;:-d in the riied duruniive fin... etc. to be useai actually I Gypsum i:.!:t . -or l-'flu -i- > > n- 0-75-l-J, 6 American Industrial Hygiene Association Journal 179 structed in this country made use of sprayed "inorganic fiber" as a fireproofing agent. States for shipboard installations during World War II. Uses of Sprayed Inorganic Mineral Fiber Insulation Mineral fiber materials containing asbestos have four major insulation uses in the construc tion and shipyard industries: (1) fireproofing, (2) thermal insulation, (3) acoustical and decorathe purposes, and (4) condensation control. Fireproofing accounts for the largest amount of mineral fiber sprayed in the United Stales. Formerly, structural steel in multistory build ings had to be encased in concrete to prevent buckling in the event of fire. The use of sprayed mineral fiber provides adequate fire protection, reduces installation costs, and reduces the weight load upon structural steel components. The use of sprayed insulation in thermal applications permits powerhouse turbines to be encased in a uniform, continuous coating which greatly reduces convection heat losses. Other industrial uses include coating of vessels in chemical plants and refineries, and insulating electrostatic precipitators, boiler breechings, and stacks. Because the newly applied surface of sprayed mineral fiber can be shaped, the materi al not only provides good acoustical control but also can be used for decorative ceiling and wall coatings for large areas in public buildings, res taurants, and similar establishments. Sprayed products containing asbestos fiber are particularly useful in controlling condensa tion in indoor swimming pool areas, laundries, textile plants, and other industrial buildings where condensation may cause extensive corro sion of structural steel. The unique wicking action uf the individual asbestos fibers serves to keep the inner mass of the insulation free of moisture. The use of sprayed nfi-.eral fiber in the ship building industry was at one time rather exten sive in Great Britain. However, because of prob lems encountered in removal during repair, its use he- now been discontinued in Gieai Britain. Very small quantifies were used in the United Inorganic Fiber Mixtures Used for Spray Application Although the composition of list- various spray products wili vary' with the ir.ientied use and the individual manufacturer, certain general formulations are similar. Most are termed "min eral fiber" materials, althuugh naturally occur ring mineral fibers are usually in a minority, and man-made inorganic fibers dominate. The material used for fireproofing in build ing construction usually is a blend of 5 to 30% asbestos fiber (chrysolile), mineral wool, clay binders (as bentonite), adhesives, synthetic resins, and other proprietary agents such as oils. Many of the materials used for thermal insula tion on turbines contain nearly 1001; asbestos fiber (often amosite or atnosite and crocidolite) plus the usual binders and adhesives. The mate rial used for acoustical and decorative purposes may contain a greater percentage of mineral wool and little or no asbestos fiber. Some mate rials are applied as a sprayed slurry (commonly known as cementitious spray) and will often, contain vermiculite, gy-psum, and shorter asbes- > tos fibers (see Table I).' Because the cementi tious material has a much greater density and increased weight per unit area, the supporting structure must sometimes be designed accord ingly. The quantity of mineral fiber used for spray applications in the United States today is stead ily increasing. In 1968 an cstirraied 40.000 tons of material were used for fireproofing alone. This does not include the amounts used for industrial thermal insulation, acoustical con trol. and condensation control. A tiiitty-story building may use 200 tons, while the World Trade Center complex being bail: for the New York Port Authority will use 5003 tons on the twin 110-story lowers fahose the fortieth floor, only nmi-asbestos-c;.-mining spt.y materials were used). The sixty-Moty Ciu:.e Manhattan Rani. Building is fireproofed wifi; 1.510.000 square feet of sprayed mineral fiber. Hie Hoi- -- - rf- 180 March. 1972 TADI E1 Composition of Sprayed Minoral Tiber Products Depending on manufacturer. the product may contain tiie following: Decorative and acoustical2 Manufactured 511 ic^lc fiber (such as Rock Wool) Asbestos fiber Mineral binder* Clays - bentonite Hydraulic setting binders Portland cement Ovcrspra) s Emulsion type sealer* Latex Acrj lie Resin pjint Thermal*1 Amosite asbestos Tiber Crocidolite asbestos fiber Chrysolite asbestos fiber Manufactured silicate fiber (such as Rock Wool) Hydraulic setting binders Portland cement Aluminum silicate extruded fibers ("ceramic") Dust-arresting additises Welting agents Oils Fireproofing (cemenIiciotis)a Chrysolite asbestos fiber Gypsum Portland cement VerinicuLite ^Contains S to 301o asbestos Tiber. ^Contains nearly 100/r asbestos fiber. New York City, there were six to eight build ings taller than thirty stories being sprayed on any given day. An estimated 2:00 tons were used in Great Britain during 196S. Use as a fire proofing agent consumed most of Britain's spray insulation material. Figure I. M:\int hoppers anil pumps used to con vey material to point of application. lund-Americun ocean liner Rotterdam contains IChl.QA') square feet of sprayed mineral fiber used f.>; fire nioiecuon, thermal insulation, and sound ai. j condensation control. Most sprayed materia! n used In huge cities. During 197C1. in 1 iptir.- 2. .it.p : ..ic-r appitiaa cd irc| i.!:_ eor.tainiitg .i Km.'S Nute wu-.li ii..-!-`:i.:l o-t ;k-or. Wi.tkc; is w.-.nir.-: tc'pirauiry ptotcctitm, matk-i;u..pr for such inivnw cxpi'Mi.-e. nh, 1972 eight 'uuild_ sprayed on ;J tens were Use as a tlre- of Britain's 1 ] t t j ...... _! .} oJ I >:. : w r i;ii I 1 - - . If i.` -U .jU.tlC A mcrican Industrial Hygiene Association Journal 01 S t^> D 181 Methods of Application There are two principal methods of applying sprayed mineral liber. In the dry inclhud, dry material is dumped from a paper shipping bag into a large hopper, where the material is agi tated and subsequently blown into a 2- or 4-tnch hose (Figure 1). The hose conveys the dry mateiial to a nozzle at the actual site of application (Figure 2). As the dry material leaves the nozzle, it passes through the focus of a ring of fine water jets. Mixing lakes place at this focal point, which is usually 4 to 8 inches from the end of the nozzle. The operator is able to control the air, material, and water mix, with valves at the nozzle. The wet method differs in that the material is premixed with water in the hopper, and the resulting slurry is pumped to the nozzle and sprayed upon the surface to be coated. The nozzle used is similar to that used to appiy plas ter. Exposure of Workmen Spraying of mineral fiber is done by men in several different trade unions in the United States, depending on its purpose and local juris dictional agreements. All material that is used for thermal insulation is applied by members of the International Association of Heat and Frost Insulators and Asbestos Workers (AFL-CIO). This is a very' minor part of their work, overall. Material used for fireproofing is often applied by members of the Plasterers' Union. Acousti cal and decorative material may be handled by carpenters, or other craftsmen. In New York City, fewer than 1000 men in all. would have regular or intermittent exposure to sprayed asbestos insulation. The application of sprayed mineral fiber compounds containing asbestos is potentially associated with health hazards for two groups of people and possibly for a third. The first group, workmen actually engaged in applying the material, is relatively small in numbers. This group, however, is the most heavily exposed. Air samples taken on site and counteJ by using a modification of the method describe'.! by TAULE I! SprayinpofThcrm.il Insertion -- lower H-.vjsc Turbn.t'1 M.in al Nu270l (l) Mjn a! Norzil i 2) Hoppe: 68 67 ss 4 5 31 100 24 32 22 S 10 6 Spraying of Fireproofing - Multistory Building Man at Nozzel (3) Man ai Nozzel (4) 30 99.0 43 94.5 20 49 34 aAll counts in fibers per cubic centimeter. Fibers longer than 5 microns. \tsible by opttcu! microscopy at 440x with phase microscopy. Our.studies have demonsiraicd that rruny mure fibers shorter than S mi* crons, too small to see by optical micro* copy, accom pany the optically u>ibic fibers and mj> exceed them in uu.Tihcr {..Ithouch not in mass} b> >eveijl *rdm of magnitude. These smaller and thinner fibers and fibrils arc detected only by elvction microscopy and are not included in counts such as these.y. Ayer and Lynch,* counting er.ly fibers longer than 5 microns visible by optical microscopy al 400x, indicated that the worker handling the nozzle was exposed to fiber levels ranging from a low of 30 f/cc to over 100 f/cc. The worker emptying the bags into the hopper was found to be exposed to fiber levels ranging from 5 f/cc to 22 f/cc. The large spread in counts can be attributed to differences in asbestos content of mateiial, work proficiency, and the ever-chang ing conditions on const ruction sites (see Table II). These dust levels are much higher than those at asbestos work sites in other trades. There are no satisfactory d:-;a at present concerning disease among these men with direct exposure to sprayed insulation dusts. Their wotk experience in general lias been too short to have led, as yet. to clinically evident disease. Among other asbcstos-expoed workmen, sig nificant disease usually does nut become evi dent for twenty or more years IV Mowing onset of exposure.10 No group of workmen engaged March, 1972 3 i i i j ' i ii < i 'i Lj 3. Pulmonary asbestosis following four year* of mineral fiber spraying experience, starling meniy-nine years belorc de.iih due to cor pulmonale. in spraying asbestos has been examined after such an interval. In New York City, we have examined a do/en inen who have sprayed asbestos. Most had worked only two or three years at the trade: they were asymptomatic, and their chest toenigenograms exhibited few or no abnormali ties. Two men had had longer experience. One, a man of 41 with fifteen years of exposure dur ing .. span of twenty-one years, was also with out shortness of breath, and his film was nor ma! apart from minimal lower lobe reticular fibrosis. The second man, the only one who had cone more than twenty years from onset of exposure, was severely short of breath, had ex tensive asbestosis on x-ray, and died of cor puluu.nale. lie had had four years of work expericisiarung in 1935, twenty-nine years before In .1 -.nli in |Oo4 at the age of 65 (Figure 3). ii experience ir, other asbestos trades is a - .:>iv. and H tneic is a consistent exposurei a.e i..pon.w lelationship, we may predict a most unhappy fate for the men who have been working in the sprayed insulation industry. Among other insulation workers, with much less asbestos exposme, observed for more than twenty years from onset of exposure, approxi mately one in five deaths has been of lung can cer, one in ten of gastrointestinal career. and almost one in ten of plcuial cr peritoneal meso thelioma. In addition, almost one in ten has been of asbestosis and cor pulmonale.11 And these disease experiences have been associated, it may be noted, with dust exposure levels much lower than at spraying sites-perhaps onetenth or one-twenlieth as high! The fate of the sprayed insulation workmen will likely resemble these experiences, although the pattern of distribution of deaths by cause may be different. Jacob and Anspach have demonstrated that, where asbestos woik ex posure is unusually excessive, there are more deaths of asbestosis and cor pulmonale and few er of lung cancer; the workmen die of pulmo nary insufficiancy before they can live lone enough to develop and die of lung cancer or mesothelioma.12 The second group, which may involve many men working in the budding construction trades in the country, especially those engaged in high-rise construction work, is much larger. Pipe fitters, welders, electricians, plumbers, car penters, and others may be on the construction site during or shortly after mineral fibers have been sprayed. On-site samples taken at various distances from the nozzle show fiber counts ranging from 70 f/cc 10 feet from the nozzle to 3 f/cc 25 feet away. Counts taken 30 minutes after completion of spray still tanged from 1 to 4 f/cc, and 60 minutes alter, from C.25 to 0.76 f/cc. Again, these counts vary because of chang es in on-site ventilation. We have few data to predict the magnitude of the disease hazard among workmen with indiiect exposure. That there is a potential seri ous risk may be inferred irom the lncie^sinc reports of ntesothelionu among men working in shipyards in which asbestos spraying was associ ated with such risk of indirect occupational exposure.1 ' Asbestosis is also found among G>7*S van ' M* . Mid i.K'SO* -n has /i nd ;iated, lex els is one* : men t*h cm use have 'i* e.\* k;\v- ' n,ii6 .c: or :*:any .;.;ion - - - -ii Ml-MT. i b. cur* iction l.^ve .:! iOilS /i'J lu Mo.es ij ; < iii . ' !* :m \i* CHS" \2> E Americai Industrial Hygiene Association Journal 183 TABLE III A/ca or Stationary Sampler Taken clunng Sprjv Operation Sample Distance from Nozzle Man (ft) Count 1 15 2 35 3 75 4 to 5 10 6 20 20 17 10 46 7! 70 37.6 66.0 Taken 30 minutes after spray operation had ceased for the day** 8 1.01 9 1.12 10 1.55 11 4.22 Taken 60 minutes after spray operation had ceased for the day^ 12 0.55 13 0.51 14 0.26 15 0.76 16 0.26 *See footnote, Table II. "Samples taken on seme floor as operation. these men,14 and asbestos bodies are delected in their lungs more commonly than among other comparable blue collar workers.15 The problem of indirect occupational expo sure in the construction trades is of importance, if only because of the number of workmen involved: In the United States, more than 3,000,000 men are regularly employed in the building trades. While the incidence of asbestosassociated disease among those indirectly exposed may be lower than among the one-in-ahundred with direct exposure, the total disease experience can be considerably greater. Our air studies indicate (Table III) that very high asbes tos fiber levels are found in the work environ ments of building trades workmen not associ ated with spraying operations, bur simply work ing in the same buildings. We may not know the incidence of mesothelioma and lung cancer among men so exposed for twenty or thirty years. In New York City, whcio spraying was underway in the 1960's, asbesu ' disease result ing from this practice, among su.initiucrs. elec tricians, carpenters, painters, ma-.om. and other Hades, will not become ewJerrt until tire Insure 4 ''..sic nom spr.o :.pp;,.^iion adhering lo buililir.e inaleiiis uwd by utiiet rrade,. 19S0's, and 1990's, and the iwenty-fiisl cen tury. Similarly, we will not he able to assess possi ble disease among (he general public for an other twenty or thirty years. We have detcimiiied that contamination of the community's air occurs as a tcsuli of miconlioilcd ot inade quately contr >!!:.! spraying opc;..;ions. As ex- 0 I s-l pccied, sue!) contamination is greatest in the u.H'iiy cf live construction site. Since most of the spraying is done before i!;c building curtain walls are erected, some of the spray material may blow outside the site. The quantity that escapes depends on wind, ii.-ir.hi of building, skill of operator, material, and control measures used. Construction sites have been studied where grossly visible waste front a spray application covered the ground to a deptlt of 1 inch for a distance extending 100 feet from the site (Figure 4). Control of Occupational Asbestos Hazards Associated with Sprayed Insulation Die two most important sources for work man exposure during spray operations are (1) material that becomes airborne during the spray operation (overspray), both that which re mains at the job site and that which blows into the surrounding air, and (2) material that re mains on the she because of poor house keeping. Until recently, few control measures were used during application of sprayed mineral fiber. During 1969 and 1970, extensive field in vestigations were undertaken by our laboratory to ascertain the possible asbestos hazard in this trade and to develop corrective measures. In this, we had considerable cooperation from the Department cf Air Resources of the City of New York, and some segments of the sprayed insulation industry, including a number of manut.-etuiins and contracting firms associated wiih ills Sprayed Mineral Fiber Manufacturers A;..ucijiion and the Contracting Plasterers' Asv'.nation of New York. Die International Asso_intii.-n of Heat and Frost Insulator-: and Asbes tos Workers. AFL-CIO, although its members d.d iiule such work (rather. Plasterers' Union n.e,ubera were encaged), also provided consider able help, since they had had much bitter ex; nence with the problem in general.16 Sint'- v.du.fole assistance was provided by the I 'imvM:.n\i]le Corporation, in keeping with -nr pcr.ai..! perspective of developing effective - '`in!: k suji asbestos uses as might be asso-: i-.d v. .i!. ii.:.'jrd. March. 1972 In this investigation, work sues were studied in eleven cities in eight states. Practices vveic found to be very much tlie same tiuoughout the country, as described above. It is our general conclusion that sprayed insulation practices can be controlled to a point at which the occupational h..cards, both direct and indirect, can be minimized or eliminated, but that such controls will be expensive, tedi ous, and cumbersome. Our findings may be summarized by consid eration of the Sprayed Insulation Regulations promulgated by the City of New York in April, 1970. These regulations were largely based, upon the results of our studies, supplemented by valuable additions derived from the experi ences of the Department of Air Resources (Dr. Robert Rickies. Commissioner) and its staff, including those of Harold Rontcr. P.E., who headed a special gioup assigned to litis problem. These regulations were the first by a govern mental agency to seek to control hazards associ ated with sprayed insulation and have more recently been followed by administrative ac tions in other cities including Philadelphia, San Francisco, Boston, and Chicago. In 1 he Matter of the ) Spraying of Asbestos- ) Commissioners Containing Material ) Order PURSUANT to the authority vested in me by the New York City Charter and the New York City Air Pollution Control Code. IT IS HEREBY ORDERED that when ever asbesios-containing material is sprayed, the following precautions si.all be taken to prevent and control the emission of asbestoscontaining particulate matter into tlie ambi ent air. 1. Before (he start of sptaying operations all floor areas shall be shoveled clean. Befote the application of asbestos-containing matetial commences, the floor of the area shall be cleared of all objects, material and equip ment other than that employed in the appli cation of the asbestus-cor.t jining insulation or all objects, materials, etc., shall be cov eted will, plastic or oilier approved tarpa.i- ..i ` Cii i- ::Sidjns .pril. ,,sed :;:cd . :'c:it Dr. ..1:0 Sill- .S.m :-.T s !> me New '-'lie !i.cye-i, .: i i o .m.i ,- all '.lore '.late.he Tl!P' i ' 'it American Industrial Hygiene Association Journal lins in a manner that precludes the subse quent dispersal of asbestos particulates. 2. The entue floor, or the part of the floor to be insulated shall be enclosed with plastic or other approved tarpaulins in a manner which shall preclude the escape of asbestoscontaining material from the enclosure. All interior open areas, such as elevator shafts, stairwells, etc., shall be enclosed in a manner which shall prevent the escape of asbestoscontaining material from the working area. "Stack effect" of the shafts, stairwells, etc., shall be considered satisfactory only if visi ble insulating material cannot escape from the enclosure. 3. Wet asbestos-containing material which has fallen to the floor shall be sv.cpt up con tinuously to prevent dispersal of dried ma terial. Under no condition shall this material be removed later than at the end of the working day. Swept-up material shall be placed in a heavy plastic bag strong enough to resist tearing or breaking under normal handling conditions and clearly marked as containing asbestos waste. The contents of the aforementioned plastic bags shat! not be transferred to another container. The plastic bags shall be placed upon a vehicle for dis posal at an approved site. 4. All floors will be vacuumed shortly after drying. The vacuum cleaner shall contain a strong, single-service disposable inner bag of durable material which shall be iamoved, then be placed in a container of the type de scribed in paragraph 3, which shall thereafter be placed on a vehicle for removal and dis posal at an approved site. 5. The materials used to form the enclosure shall be thoroughly vacuumed upon comple tion of the application of the insulation in the area. The entire floor ;nea. all Sedges and surfaces including tarpaulins njv n which waste insulation material may have tV.IU-ri, shaii then be vacuumed or levacvumcd be fore removal of the enclosures. o l*$ H 185 6. Enclosures shall not be dismantled until the area has been thoroughly vjcuumed alter completion of sprav ing and cleanup. 7. All areas used for opening bags containing asbestos insulating material and/or charging of hoppers shall be enclosed in such a man ner that asbestos-containing insulating mate rial shall not be permitted to escape from the immediate area in which such activity lakes place. 8. Signs shall be posted outside enclosures warning persons of the hazards of entering the enclosure without appropriate mask and other apparel. 9. All persons involved in the spraying of asbestos at the site must be furnished with Bureau of Mines approved respirators for pneumoconiosis-producing dust or equip ment as required by N.Y. State Department of Labor and must be furnished with suit able coveralls which will be left ai die site and thereby preclude the ismoval ot asbes tos from the site. No person shaii be permit ted in an area in which asbestos spraying or handling has taken place until final vacuum ing referred to in paragraph numbered `5' herein, unless such person is furnished with and wears a Bureau of Mines apptoved res pirator for penumoconiosis-producing dust and coveralls of the type described herein. Facilities shall be provided and procedures instituted and supervised that preclude the removal and dispersal of asbestos-containing material from the construction site on the clothing or other appurtenances of persons leaving the area. 10. Any plenum or other structures coaled with asbestos-containing insulation which is intended for use in the ciicul.iiiun of air in the building must be thoroughly cleaned of all debris ar.d waste inflation. Aii applied asbestos-containing insulation within a plenum oi duct mi.';.! he ccat-d v.::n c seal ant which precludes e.-.p->sure '.lie achestos-coiitamiug m.uenal in the ciicul.i'.ing air. 11.6 ] |. A person shall be assigned the full-time responsibility to supervise the spraying and related operations to assure that no asbestosbearing mateual is released from the con struction site. 12. In case of emission of asbestos from the construction site, immediate steps shall be taken to cause the cessation of such emis sions by either effective control measures or work stoppage at the source of the emis sions. There shall then be immediate and complete cleanup of all material that has es caped the construction site by measures that will insure that no further dispersal of any asbestos material into the atmosphere can occur. 13. Notice of intent to spray asbestos-con taining material on any premises shall be given to the director of Field Sendees. De partment of Air Resources, 134 Centre Street, New York, N.Y. (212-566-2735). Said notice shall be both oral, by telephone, and in writing and shall specify, at least two (2) days prior to said spraying, the floors on which the spraying will take place. It will be seen that these early regulations (they have since been strengthened) were di rected largely to the prevention of the environ mental hazard. In addition, we were able to identify a number of other approaches which were more specifically concerned with the oc cupational hazard. Reduction of Airborne Asbestos during Spray Operations Currently, consideration is being given with in the industry' to several proposals aimed at ieJnrinr the amount of asbestos dust winch might become airborne during spraying. An important approach includes elimination of luhesios from the material used and the addt i"U o! oils or wetting agents. Formulation -inm;.VN h.r.e met with some success. Several inters are now producing materia! wm-t. contains no asbestos. The disease poten 07 5 Mjrui. 1972 tial of these substitute materials is largely un known, and New York City regulation: require the same precaution-, during their appl.cattcn. as with asbestos-containing materials. In Great Britain, the .modification of spray equipment lias received considerable attention. A method of ptewetiii-g the fiber lefeve con veying material to the nozzle has been devel oped. Although this prewetting process signifi cantly reduces fiber counts during applications, the method does not yet lend itself to volume spraying as done in the United States. Progress has been made in developing effec tive means of enclosing areas during spray appli cation (Figures 5 to 10). Several contractors have custom-designed canvas or reinforced plas tic tarpaulins with various flaps and interlock ing closure devices. Wooden frames covered with reinforced plastic are in use. Not only must the perimeter be enclosed, but the stair wells and elevator shafts must be sealed to pre vent the stack effect from carrying dust and fiber to the outside aluiOsphcie. Some rather unique ways have been developed for enclosing outside spandrels and columns prior to spray ing. Since the design of buildings may differ widely, methods for enclosing must be individu ally tailored for a particular structure. To elimi nate the need for temporary enclosure of build ings, some contractors are rescheduling the spray application to permit prior erection of curtain walls and glazing of the window open ings. Enclosure with canvas and plastic lias mark edly improved since enactment of more strin gent regulations. Ambient air samples taken near spray job sites that have been enclosed by means of newet methods have shown that ex cellent containment ii possible. Asbestos fiber emissions from properly enclosed spray opera tions were not detected with the light micro scope. Electron microscope examination of samples is currently under way to determine if the spray process adds significantly lo the as bestos fiber background level in ambient air. In limited studies, it did not. Enclosure :::cirg. however, stilt has rot solved the pro1-.!nf wind erosion dining the interval between com- un* >;i. ... i> ns, . ulume .wiors - plaS` . . VC i C d : c i.!;.' siair- -...pic. s: _nd i.aiier buildin; the .lion of op.n.s mark. suin; taken n'-oc: by e.v s liber y opcra' micro- li 'tl of n ait. In of American Industrial Hygiene Association Journal I I o-7 s' 13 y 17 Work Practices II is our conclusion that rmiuh can be done to reduce dust by the individual worimiji: on the job. in his everyday hai.-iling of the spray muten.il. Methods of opening, etnptyir.t. and stacking bags, proper methods of using and ;djustir.c the no7.de. and methods of pancnal protection are important. Attention to seeming ly small details by the worker are important, and these should be the object of training and education programs. The sprayed mineral tiber manufacturers association has prepared a book let outlining such improved work practices. Too Figure 5. Floor of building after spray application. Note piles of waste asbestos-containing materials and (lapping tarpaulins, inadequately secured. *4 f . tow * * - *Wf P. I... Jk aJ 3 1* i t i. . : . -i . a ^ i . ^ ;J . -i Figure 7. Wind end weather damage to enclosure canvas. I L3 M . (3 4Si'sa bs MB BC Ml U OX K KJ ll CZ U1 ICt Ci B Figure 6. Multistory bunding inadequately en closed with canvas. Note openings lieie tarpaciins have not been secured. plction of spray and erection of "skin" or cur tain wall. Architectural awareness of this prob lem may permit design of future muhi'tory buildings to ensure erection of curtain walls be fore foray fireproofing is applied. .Schedul:;'-:! is no simple matter, however, and this may be verv difficult. > . .: . f'i . ..... , l . . * r 4 4 v . . ..... *,..14^ Fauite I ti-l. 'Uic n;1i-.rt-.*^ t laced canvas and plus tic tatp.suliM. with l____ O 7S )^> K March. 197? Ihe supervisor or foreman. His task, however, should also be lightened by the development of procedures which do not depend upon work man cooperation, skill, knowledge, training, or dedication to safely. Elimination of hazards should be built inio the u or!, procedure' Other wise, if an\ thing can go wrong, it well ir.a\. ur.J the price of failure is unacceptable. This is not to say that the on-site operations 1 of the workman are not important; of course, 2 they are. One area in which no planned pro 1 gram, however effective in principle, can be suc } ) j ZjtfisZ.?. :J V I Tijure 9. Cuv'.om-fjbricated tarpaulins for building enclosure. Note tongues and tie-downs to prevent ma terials from dropping along the side of the building. cessful without workman cooperation and un derstanding is housekeeping. In our studies, we found that quantities of waste sprayed mineral i fiber are still allowed to remain on the floors, ledges, and nearby equipment (Figures 11 to 13). Asbestos-containing waste is often tracked i i underfoot on a_ construction site for many months. In some cases, because of peer house keeping, waste fibrous material is allowed to re main in ventilating ducts and dropped ceilings to contribute to lifetime contamination of the i structure. Experimental work is now under way to re design existing commercial vacuum cleaners to permit their use in construction cleanup. Wet s pickup of large volumes of material and collec tion in disposable bags are two features which must be included in a redesigned unit (Figures f igure 10. V-here a long span exists between col umns, the tarpaulins must be securely fastened at the bottom to prevent flapping in the wind. i much reliance -hould not be placed, however, on diligence and training of individual work men. We have found that work crews are inconi.tni, with inexperienced men often added as be volume of wotk increases. These men. at "liter limes, do plastering, and spraying of in'th.iiton may be only intermittent employment i"i litem. Few comraciors employ a constant "'h I'otce. and apprenticeship programs have ' ""eti .cant and fragmentary, where they exist, r; litis country. i'.atiut. ehi tcation will have to be a constani. 'i ."ita; .iif.nr and often the responsibility of v. :. k Figure 11. Asl'esi(*5-civnt;iintnc wotre allc.'.od U-. re-, main iti litr.u.'d avc* ;i;ca . :\J v.r.til.iitic c'.r...i:i of completed btitldii.. v. er. .i ; of o. k,rg. or :/ards ' (hherr.. cr^tions . course, :cd pro- he SUC- and un..Jiis. we. mineral floors, ;> 11 lo : ir.ickcd r mans' house- ed.io re; cCiiiiiCS oi tnc io rc. t.jis to -T- Wet >1 colleci .-s w hich (Figures i. :i .-I o I3 American Industrial Hygiene Association Journal 1S9 14 and 15). To reduce the number of men ex posed and lo facilitate easy cleanup, several of llic general contractors have begun a program of carefully planned work schedule*. The men and material of other trades are kept off the floor until the spray and cleanup are completed (Figure 16). s Respirator Protection Personal protection of the workers applying the spray material is an area that needs consid erable attention. We found that many men ap plying sprayed mineial fiber containing asbestos did not wear any personal respiratory protec tive device. A very few wore disposable respira tors, and a few wore more conventional types. Prior to 1970, all disposable respirators avail able on the market were totally unsuitable for this specific use. Progress being made in development of new respiratory protective devices is indeed encour aging. Many major manufacturers of such pro tective devices will probably have an effective disposable unit available sometime during 1971. It is hoped that a device of this type will have an ovetall efficiency great enough to adequately protect many men working in the general area of the spray operation although not near the spraying itself, nor within the sptay enclosure. \ ! J I 1 Figure 13. Uncovered pieces of equipment ion on the floor duiing spray application collect debris from the spray operation. i 1 1I * ! Fignic i4. Waste material siumiti be pWiieU up and packaged in tightly closed containers. t i.-iuc 12. root 1.-1iI^ukCv'i't:*--. V..i.ivCu-. pr.iv niali-ri.il nn-cring c-andmi box v.i:-.:v other frails tv. iv work weeks ur months later. Nevertheless, because of the high fiber counts, 100 t'/cc, a conventional filter-type respirator will not provide adequate protection lor the worker handling the spray noz'le or for other workers in the enclosure. In such aicas. some type of supplied air respiratot must be used. The chief fault of many of ilie available sup plied air units is their bulk. Here again, great piogrers is being matle in the development of small bell-carried units (Figure 17). A quick look at the filvi counts in a, ..>a> ate as at or near the spray operation p.dtti-. the neej lor mandatory effective respiratory protection. -vr i ;< March, IV 72 be-few men have reached twenty years from onset of work--but of young men who luve been regularly employed i:i '.praying asbestoscontaining insulation materials n is pcsstcle that a majority will die o! asbestos disease, in cluding lung cancer, pleural and peiitoneal mes othelioma, and asb-'stosis. Our studies indicate L . Figure 15. Waste material being transported to des ignated landfill areas in covered trucks with packages secured to prevent the spread of material through streets and roads. Two steps are essential to speed the use of res piratory protection in the spray insulation trade: (1) a device more acceptable from a standpoint of worker comfort and (2.) a massive educational program among these workers. Discussion Investigation of the sprayed mineral fiber in dustry indicates an important asbestos hazard exists for woriemen employed in this trade. It is too early to tell how severe the death toll will f r~ Figure 17. Because the spray applicators are sub jected to high concentrations of asbestos fibers, some type of air filtration or supplied air respirator is neces sary. A prototype of the Burgess filtered air respirator. ____ ,i lL i '-' ire 16. Cr.Jr"ed areas should be appropriately ''..I i ptacn; oilier trades Irani entering the area that they have been exposed to asbestos dust levels otherwise seldom seen nowadays in the asbestos industry. An equally unacceptable hazard may exist for other construction workmen, exposed on constitution sites to dusts derived from spray ing operations. Wliile such indirect occupational exposuie is intenniilcm. it is still at levels found in othei nades to have high risk. Unfor tunately. intemiitient high peak expostnss may eatry the potential of sctnms disease twenty. ; I mm I*.. o Vti.ij- ...M.. !Ti.yes. f I :s are su`- "l-.h, ".'ins Mi neevs.: :c:p::_nn. .'.'.'`5 rii.'St in ilis M.iV CXlsl on :n sri'.'v- mal i.-.c!j . 1'; ;-.r- ' 't i i i \i y * iv. uWU'lS -fai r-lf f*^~ fa JKfa O 13 Is/ American industrial Hygiene Association Journal 19) become lodged in the lung. Once in situ, the fi bers continue to exert their effect on contigu ous tissue; while the individual may be spared further exposure, his lung and other tissues are not. Construction trades workmen employed in buildings in which spraying of asbestos fiber in sulation was done should be considered to have been subject to asbestos exposure and risk. In formation is inadequate to predict the magni tude of this risk; it may be considerable. Such occupational hazards are intolerable, and it is evident that they will not be permit ted. In addition to efforts by regulatory agen cies mentioned before, construction unions, too. have taken steps to protect their members. Work stoppages have occurred in New York City, Westchester County, and elsewhere, with men in various trades refusing to work during spray operations. If administrative regulation is unavailable or ineffective, self-regulation by la bor and employers in the construction trades may be substituted. Our studies suggest that the occupational hazard associated with spraying of asbestos in sulation can be minimized or eliminated by suitable industry procedures. Such controls, as noted, will be expensive for the sprayed fire proofing industry'; the burden in the competative market place may make the product and process uneconomical, to give way to other means of fireproofing and insulating. Should this occur, it will simply mean that the health of workmen must be considered in weighing the cost of work done. On some scares, as this one, health will weigh heavily. The alternative to controls will be banning the spraying of asbestos materials. While, as a general rule, control of environmental hazards seems preferable, if control measures are nei ther feasible nor effective, or if they arc ignored or disregarded, banning will be considered. Note: Since this manuscript was submitted, it was determined ihar the existence of the N.Y.C. Department of Air Resources had failed to ensure adequate compliance for the conliol of the spraying of a.-besto* miners! fiber illa tion. The New York City C*.-ii.\...' banned all spraying of asbenos in N.Y.C. effec tive February 25. 1972-Locsl Law 40. 1971. Air Pollution Control Code, Section 1403.2-9.11(B); enacted August 25. 1971. References l.Selikoft, I.J., ct at: Asbestos and Neoplasia. Amer. J. Med. 42:487 (1967). 2. Doll. R.: Mortality from Lung Cancer in Asbestos Workers. Bril. J. Ind. Med. 12.SI (I9SS). 3.Enticknap J.B., and W.J. Smilhrr: Peritonei! Tu mours in Asbestosis. bn I. J. Jnd. Med. 21:20 (1964). 4. Mcrevvether, E.R.A.: A Memorandum on Aebestosis. Tubercle 13:69. 109, 1JZ (193M934). 5. McNulty, J.C.: Asbestos Exposure in Australia.Mternational Conference on Pneumoconiosis. Jut.annesburg, 1969. Proceeding.' (H.A. Shapiro, ed.), pp. 201-203,Capetown, Ox lot J University rVes<il9'''j).. 6. McDonald, J.D.: Research on Asbestos. McCiit Reporter 2:18-19 (1970). 7. Scliknff, I.J., J. Chur;, and E.C. Hammond: Asbest 10s Exposure and Neoplasia. /. Amer. Med. Assoc. IS8:22 (1964). 8. Lynch. J.R., and H.E. A;. :r: Measurement of Dust Exposures in the Asbestos Texme tnausiry. Am. Ind. Hvg. Assoc. J. 27.431 (1966). 9. Nicholson, W.J., A.N. Kohl, and E.F. Tcrra-rd: As bestos Air poiluation in New York City. Seisnd In tern. Clean Air Ccmgr. Wcy.ingtor.. D.C.. Ceee'r.ber 19 70, In press. lO.SsMkoff, IJ., J. Chu:;, end E.C. Kammor.d: The Occurrence of Asbestosis amon; insulation Work ers in the United States. Ann. .Y. Y. Acad. Set 7.72:139 (196S). 11. beiikuff. I.J., E.C. Hammond. J. Chur;-. Mortality Experience of Asbestos Insulation Workers, inter national Conference on pneumoconiosis. Johannes burg. 1969. Proceedings iH.A. Snapir.v. ed.). pp. 1 S0< 1 86, Capetown. Oxford University West (1970). 12. Jacob, G., and M. Anspach: Pulmonary Neoplasia anon; Dresden Asbestos Workers. Am. .V. Y. Acad. Sci. 132:536 (1965). 13. Harries, P.G.: Asbestos Ha cards in Naval Dock yards. Ann. Ctcup. hyp. II.135 (1968). 14.Sheers, G.. and A.R. Templeton: Effects of Asbes tos in Dockyard Workers. Brit. Med. J. S:574 119o S). l5.Selikoff, I.J., and E.C. Il.'inmnnd: Asbestos Bodies in N.Y.C. Population in Two I'etiuJv of Time. In ternational L'on.irrrncr on Tneunioc on:..-sis. Johannesbuig. h.i-9. PiocetJi-itt <ii. bh-piro. ed.). pp. 99-IU5, Capetown, Oxiutd Lmwi.ity Ptess (1970). 16. S.likolf. I.J.: Pcrtncrsl.ip lor i're'ention. Ind. Med. burg. 39(4):2l (1970). Received August 3. 1971