Document X8D96NBm2qZ191r6dN6bqv8VG

FILE NAME Roofing ROOF DATE 1980 Oct 27 DOC ROOF005 DOCUMENT DESCRIPTION Aherne & Levine Master's Thesis - Evaluation of Asbestos Exposure from Asbestos Removing Coro eee ee ee ee eee + ah te ee, Evaluation of Asbestos Asbestos Asbestos Asbestos Asbestos Ro Roofing fing Roofing Removal Removal Removal Removal Joseph W. Aherne 27 October 1980 Professor Lester Levin Industrial Hygiene Submitted as partial fulfillment of requirements for Master of Science degree in Occupational Health ecm ome me ee tee oe -- Introduction In the past few decades . the marvelous advantages of an in- flammable resistant fibrous mineral which inspired the Greeks to call it asbesta meaning inextinguishable or unquenchable have paled in comparison to the impact it has had on thousands of workers problem is and their families The magnitude of . only now being realized.Studies have the asbestos been completedcompleted completed completed completed on the working environments of several occupatioannsd also on the workers families In addition monitoring studies have been completed on the environments of buildings within which asbestos materials materials have been nave been used used in construction ,, in construction Asbestos fiber fiber exposures evaluated evaluated in the mining mining mining and milling mmilling illing of asbestos asbestos asbestos , in- industry4 sulation trades and in the irywirywalall construction The synergistic effect when a Trotte smoker is also exposed to asbestos fibers results in an extremely higher probability of carcinoma . It has been estimated :. smokes has approximately 90 times that an greater asbestos worker who i probability of con- tracting cancer than the smoker The occupational risk due to asbestos exposure to roofers has not been investigated to any great extent plete survey of the literature discovered to this date A com- feur w only couple preferences which demonstrated only a minimal exposure However most of the monitoring performed for these studies was during the applica- tion that It of new roofing material is more reasonable to assume when when fiber release would occur during tear oopp erationsoperations erations as the weathered roofing materials are being removed 5,7 The life of a roof ranges between 10-25 years . Over this this life life time the worn As materials are weathered thereby the weathering process continues becoming brittle and the asbestos fibers which originally had been fixed into an asphalt matrix may be- come locsened When the shingles and roofing felts are removed - these fugitive fibers will become airborne resulting in a health hazartdo the worker and to the populace in the neighboring community The Tear Process When a roof is replaced the shingles and felts felts or the built up materials are pulled off the roof and discarded to a roofing trash bin on the ground This procedure causes the destruction of the shingles roofing felts and other materials During the process a significant amount asbestos content directly of dust is produced in which the dependent on the amount in the | roofing materials Shingle roofs are for the most part installed on residential the structures therefore .asbestos fibers released fibers during removal create a greater potential for exposure to the general public industriv than do those released from commercial or buildings Shingles off with are the removed completely by hands or with the aid hand tearing of small hand the shingles tools claw hammer and crowbar Built up roofing is generally installed on commercial or structures These are composed of a layer of insulation industrial covered by a couple layers of roofing felt with hot asphalt spread on top and slag stones placed in the molten tar The removal of these is accomplished by a combination of mechanical and manual tasks The slag stones are removed with an industrial vacuum or swept up with orcoms Gasoline powered roof cutters are employed to section the roof in small pieces 2'x3 ) These sections are then stacked on wheelbarrows and transported to the edge of the roof where they are discarded to the ground The sectioning are- cess creates a great amount of dust and since it usually con- tinues simultaneously with the removarl emoval the potential for asbestos fiber exposure is great when the roofing felts or insulation contain asbestos The workers werd supplied not with any type of respirators dr or masks for protection However some did wear kerchiefs for L " their own protection Composition Composition of Roofing Materials 5,8 The asbestos content of roofing materials varies with the manufacturer and also with the type of product i.e. felt shingle insulation The basic material used to manufacture - ra most roofinrgoofing products 5-p1r0o0ducts varies from 5-100 . is is asbestos paper The type of asbestos The ashestos cortert is chrysotile in all instances This results from the fact that this type is mined \ Canada and therefore is inexpensive This paper is then impregnated with compared to the other asphalt to prepare it types suit- ably for roofing felts and shingles Asbestos 45-65 product is 15-25 for shingleansd 45-65 for content in the 5 the felts final a te a oem et coating Flashing cement and roof also contain asbestos 15-45 and 3-25 respectively However these products viscous throughout their life and therefore fiber fibers remain release is unlikely Asbestos fibers are used in roofing materials to improve their longevity and the tensile strength durability of the products It increases the to corrosion and rot and heightens resistance it greatly improves the insulation value and fire resistance potential Materials and Methods Site Description Host roofing contractors are small businesses with only a few employees In these cases the roofers usually homes with one or two trucks depending depending on the work size out of of the their parti- parti- cular job Companies with larger work forces also exist but generally these companies do larger commercial and industrial roofing Nevertheless whether the company is large or small employees most arrive at the site ready for work and return home directly These work practices create the potential for asbestos to the workers family exposure This report contains an evaluation on industrial sites The number of of the latter type of operation men needed for each job de- pends directly Two sites were on its size and the estimated selected after a considerable time for completion amount of difficulty due to the lack of activity in the roofing industry during the - eee? tee i re nr. i id a are . period of the research project The sites were of the commercial type each with a builtup roof each covered with slag stones The roof in case was removed as describe above Sampling Airborne asbestos dust samples were collected in accordance with the NICSH recommendedrecommended method 9,10 Samples a portable sampling pump to draw air through a are collected using 37 mm 0.8 micron Millipore pore size Type AA membrane filter Air is pumped rate through the filters at were collected by attaching of 2 liters Personal samples the filter to workers collar by means were collected 4-6 feet off the of a clothing clip Area samples ground to determine general rate was checked frequently environmental exposures The flow during sampling The pumps were calibrated before each use with the Kurz Flow Calibrator Fiber Determination The filters were analyzed using the NIOSH approved membrane filter render method The opaque filters are chemically chemically treated to them tranparent The asbestos fibers are then sized and . counted Fibers 5 microns are counted and fibers are lated from the sampling timeand flow rate The asbestos calcufiber by an ACGIH accredited laboratory and the count was performed fiber calculations were completed by the researcher Results and Discussion Discusion Discussion The fiber exposures are tabulated in Table I and summarized in Table IT The results show a trend in exposure from very little TABLE TABLE TABLE TABLE I Airborne Asbestos Exposure To Roofers Position of Sample Sample I.D. Number Sampling Time Min Sample .Volume liters ; Site Fersonal IMR 55 " , -2 40 110 90 " -barrow " -operator ' Area wind " -3 LU -5 -6 -7 -8 55 45 - 50 35 37 53 110 90 100 70 74 106 -up wind . Site Personal -barrow " Area wind -down wind Personal Personal " -9 5-1 -2 -3 -4 -5 12-1 -2 95 190 50 100 50 100 50 100 60 120 . 55 110 22 44 novnouamnoop 24mi 48 - ... -3 novnouamnoop 24mi 26 , " -4 20 Ct 40 11 11 -loader " -5 -5 -7 - | -8 20 N 7 18 Ae 26 48 36 H . Area wind -up wind _ -down wind BLANK -9 -10 -11 -12 . *** *** 13 60 41 21 ** rn 7% 26 120 82 42 *** Concentration fibers 5 microns Der CC 0.18 0 : 0.08 0.13 , 0.23 0.29 0.08 0.03 0.05 too heavy to 0.06 0.09 O count 7 ~~ 0.05 0.13 0.13 0.11 0.21 0.06 0.22 0.12 0.16 0.11 ~O- 0 0.07 . --O - Loader- these workers stacked the sections onto the wheelbarrow - Barrow man- pushed the wheelbarrow and discarded the sections to Operator- manned the the dumpster on roof cutter the ground which sectioned the roof for the background readings to a significant exposure for some of the workers The wind area samples which determined the background levels of less than 0.02 quite low ranging ranged from 0-0.05 fibers with an average fibers The wind samples were also from 0-0.08 fibers with an average 0.05 fibers  - ee ae eeey or rs TABLE II Summary of Airborne Asbestos Exposure Pocition of Sample Area wind -down wind Number of Samples Ma Ma Sample Time Min Range 41-95 21-55 Concentration fibers Range Mean 0-0.05 0-0.08 40.02 0.05 . Personal -barrow -operator 7 7 9 1 13-55 13-50 35 . 0-0,18 - 0.06-0.23 0.29 0.10 0.15 0.29 The area samples were collected approximately 50 yards from the work exposure site at levels feet to the general populace above ground to in the vicinity determine the The difference between the wind and wind samples is not large enough to | conclude definitely that the tear procedures create a hazard to the public However the particular situation must be con- sidered in order to explain these results In both cases the buildings being released in the worked were 50-60 feet high so the fibers process could easily have been distributed over a sufficiently large area to appear insignificant - The personal samples show somewhat higher exposures Three y different tasks were monitored The loader removed the cut sections from the roof and stacked them into the wheelbarrow These exposures ranged from 0-0.18 fibers with a mean 0.10 fibers The wheelbarrow man pushed the stacked sections to the edge ot the roof and dumped them to the ground The asbestos exposures in this case ranged from 0.06-0.23 fibers with a mean 0.15 te: ~ &- ome fibers The reason the difference in these exposures is most probably due to the work practice of throwing the cut sections onto the wheelbarrow so that clouas of dust were created The worker who pushed the barrow received the full brunt of this dust cloud The man who operated the roof cutter was exposed to the greatest amount of asbestos 0.20 Sibers This task was visibly the most dusty because as the cutter sectioned the roof it pulverized the roofing felts and insulation in the pro- cess However only one sample could be collected , therefore the results cannot be assumed for every case Relationship to Recommended Exposure Limits In light of the carcinogenic nature of asbestos the recommend- ed standards and legal limits are constantly being reevaluated and revised downward Presently the OSHA standard for an R hour than time weighted average is 2 fivers 5 microns in length with a ceiling of 10 which are fibers has NICSH recommended a TWA of 0.1 fiber with a ceiling of 0:05 fibers because of the carcinogenic nature of asbestos ACGIH has revised its limits in the intended changes for 1978 to 2 fibers for chrysotile asbestos Since chrysotile is the asbestos form used in the roofing industry this limit is agree- | with the OSHA standard . Therefore the asbestos exposures evaluated herein are significantly below the legal limit set by OSHA and also below the recommended ACGIH llimit imit however the NICSH recommended standard of 0.10 fibers is exceeded for each of the tasks monitored 9- Conclusions and Recommendations It is impossible to extend the conclusions of this report to the entire roofing industry Because roofs are installed only every 15-25 years the records concerning the old roof are im- possible to obtain therefore roofing felts and insulation the are exect composition of unknown The roofing the con- tractor can identify the materials as asbestos or rag felts or the insulation as fiberglass or asbestos but in most cases the manufacturer cannot be identified and therefore the percent- ages of various materials is nascertainable In light of this caution a few comments are in order The tearoff operations compose only a short part of each day approximately one quarter therefore if some precautioanrse followed during the ripout the asbestos fiber exposure will be reduced To protect the workers workers disposable respirators should be at the start of each tear period Inasmuch the distributed periods are worker normally short cooperation is more kely than if the masks were necessary for the entire day ~ ee ee aed REFERENCES 1 Selikoff I.J. and E.C.Hammond Health Hazards of Asbestos Fynsure Ann.N.V. Ann.N.V. Ara^-.Sci Ara^-.Sci 1_R14 2 McDonald J.C. M.R.Becklake G.N.Gibbs A.D. McDonald and C.E.Rossiter The Health of Chrysotile Asbestos Mine and Mill Workers Arch.Env.Health 61-58 3 Selikoff I.J. F.C.Hammond and J.Churg Asbestos Exposure Smoking and Neoplasia J.A.M.A. 204 106-110 1258 Exposure Occupational 4 Verma D.K. D.K. and C.G.Middleton Exposure to Asbestos in the Drywall Taping Process A.1.H.A.Journal A.1.H.A.Journal , 41 264-259 5 Mannville Corporation Frivate Communication Director Environmental Services Health Safety and Environmental Development 1980 6 Asbestos Information Association Engineering Feasibility and Economic impact Study of a Froposed CBHA Regulation on Cccura- tional Exposure Exposure tional Exposure to Airborne Airborne Asbestos in in the Construction Construction Construction Industry 1977 7 Levine .: An Asbestos Information Resource 1977 8 ) & Consumer Product Consumer Consumer Consumer in Products Safety in Consumer Safety Products ; & & - Fact Sheets Mission Mission Mission Mission 1978 ) Review Review Review p V of of AA shasts os has Ashastos tosAshastos lice Product Asbestos Product . 9 NIOSH Occupational Exposure Sampling Strategy January 1975 10 NIOSH Manual of Sampling Data Sheets 1977. Sampling Data Sheet 32.02 DHEW 77-159 . 11 NIOSH Revised Recommended Asbestos Standard U.S.DHEW 12 TLV's Threshold Limit Physical Agents in the Changes for 1980 _ Values for Chemical Substances and Workroom Environment with Intended a - a 2) tay ee ae ny SES NN HO at meee tin cos e Oo Se mE re we oe. e em eee ee : _. Manville Sales Corporation Caryl Panch Denver Colorad 50217 Edniynd M. Feliner Vice President Director Environmental Services Health Safety & Environment Department January 14 1980 mee wee _ - ee me Mr. Lester Levin | Professor of Industrial Hygiene. Drexel University : Environmental Studies Institute Philadelphia PA 19104 Dear Mr. Levin In reply to your letteorf January 9 containing roofing materials containing compressed gaskets I have 1980 relative and asbestos- the following to comments . + - There are major tyrf tyrf tyrf containing poofing materials used in the pa and today asbestos roofing and siding shingles and asphalt saturated asbestos roofing felts The shingles were generally used in residential applications and the roofing felts on commercial and industrial buildings The shingles normally containcontained ed 15-25 asbestos and the roofing felts 45-65 asbestos chrysotile in both cases - The length of roof service prior to replacement is highly dependent on the type of exposure Built roofs generally have c life of 10 to 20 years Domestic roofs frequently last longer than 20 years We have considerable fiber release data relative to the application and removal of asbestos felt built roofs and a limited amount of data collected during the rapid demolition of a house built with asbestos roofing and siding shingles These data which are enclosed were all collected and analyzed by the NIOSH occupational monitoring procedure For your information the Navy Regional Medical Center at Bremerton Washington Puget Sound Navy Yard did extensive testing to determine the airborne fiber levels generated during various operations involving containing compressed gaskets including during gasket removal and removal of residual material The study is entitled en oo ee nee een 2GaN emanat aee ed - me ee eee we eee coe te Or ave ee aoe - . . Re, cme Cee ee 5 een ne me tee ee Page 2 Asbestos Exposure from Gasket Operations and was published in May 1978. The summary from the study report is enclosed Please contact me if for your purposes these comments are insufficient Very truly yours - tte os . ~ Lb hte ra _. Ti f :7 an choge Ti Ti Ti oe 2 a rs EMF jh Encl &: ms - - . @ he aaa aoa ddan ORaeE ee aO nderen vo ita ie Oh rt itn aia eee LAL PED a aan vg te ae garretts TS he FROM JON MANVILLE AIRBORNE FIBER CONCENTRATIONS | ASBESTOS ROOFING FELT - INSTALLATION AND TEAR Date 3-14-74 4-10-74 - 5-21-74 . 7-25-74 11-20-74 12-16-75 8-16-75 ae, 8-16-75 5-9-77 Location Gilmore Jr. H.S. Racine Wisconsin Ben Davis H.S. Indianapolis Hess Dept. Store Allentown PA Tolletson Jr. H.S. Gary Indiana Job Type New . ; Monitoring Data Fibers 0.2 to 0.6 ' Tear | 0.1 to 0.4 Tear 0.0 to 0.2 | . & New Roof }: Tear 0.1 to 0.3 7 $ New Roof Cherry Creek H.S. 2 Denver Colorado New 0.1 to 0.2 _ Madden Bldg Inverness Denver Colorado New . Less than 0.1 3 Anderson H.S. Anderson Indiana 45 , Tear & New Roof Less than 0.1 Chesterfield G.S. Chesterfield Indiana New Less than 0.1 Manville Waukegan IL ; Oo . Tear & New Roof Less than| 0.1 to 0.3