Document 44xjekR800a1k1LaRwB6xDeJx

* PLAINTIFF'S EXHIBIT 5 G-571 THE ACTUAL COETRIBUTIOE OF AIRBOREE ASBESTOS FTWIOgS TO sgc OCCUPATIORAL EXPOSURE OF KT-CTAWnptS DURIEQ sKT.ncnm PROCESSIEG OF EECAPSULATED ASBESTOS ,, OPENING OF OLD FLANGES AND REMOVAL OF ASBESTOS GASKETS CARL A. MAEGOLD, CH OVXRODCEirTAL COKTROL SCIXECES, EEC. BELLEVUE, KASHIEGTOE 'JAXUARY 1989 ABSTRACT Asbestos gaskets are removed from flanges and machinery by first disassembling the pieces. The asbestos gasket is then pried loose with a sharp instrument. Sometimes, the gasket will have been so compressed that residual parts of the gasket are left stuck to the flange faces. This.can be removed with a sharp instrument. - Sections of piping were removed from a 0.S. Navy vessel, the USN Gypsy (ARSD-1) which was built in 1944, served in the Pacific Theatre in World War ZI, and was decommissioned in the 1950's. Some of the gaskets in the piping flanges collected for opening may have been in place'up to 40 years. Gaskets are not normally removed unless there is a reason; overhaul, leakage, or aachlnery removal. Eight flanges were opened over an 6 hour sampling period to determine the 8 hour time-weighted average. Not all the gaskets bore the Garlock logo, but all gaskets were similar and were determined to contain chrysotlle asbestos. The air samplers placed on the operator and 5 and 10 feet away from the operator recorded the release of chrysotlle asbestos ' fibers in the air from the opening of flanges and the removal of asbestos containing gaskets. The operation was conducted in a clean room and low levels.of natural asbestos. - ' x The results showed that; 1. The electron microscopy analyses for total chrysotlle fibers averaged .002 structures/ec. Structures/cc is approximately equal to fibers/ec. 2. The electron microscopy analyses for ehrysotile asbestos fibers greater than 5 micrometers in length and .25 micrometers in diameter were compared to the phase contrast microscopy method. The results showed that there were no chrysotlle asbestos fibers present -greater than 5 micrometers in length at concentrations above the lower detection limit of .002 structures/cc. This is a method of verification of the phase contrast microscopy method-. 3. The phase contrast microscopy analyses revealed the average concentration for fibers greater than 5 micrometers was .001 fibers/ee, or slightly greater. The personal sample attached to the operator opening the flanges and removing the gaskets was .005 flbers/cc. The phase contrast microscopy method is the only one specified for analyses in the Federal standard. The eight hour time-weighted average to the operator and to a by-stander in the room are fractions of the dally permissible exposure limit of .2 flbers/cc. TABLE OF corrms ABSTRACT TABLE OF CONTENTS BACKGROUND ENVIRONMENTAL EXPOSURES VOLUME OF ASBESTOS USED INSHIPYARDS EXPOSURES OF THE CONSTRUCTION AND SHIPYAXD TRADES CURRENT ALLOWABLE LEVELS OFEXPOSURE CONTINUING EVALUATIONS U.S. NAVY GASKET REPORT VERIFICATION OF THE NAVYGASKET REPORT THE -DILEMMA EXPERIMENTAL DESIGN REFERENCES RESULTS AND CONCLUSIONS . 1 1 2 fi 7 8 9. 10 11 13 IS 17 21 24 1 'Ukl .1 1. BACKGROUND: A*be*to* Is one of the most plentiful, useful, end cheap Industrial minerals. Because of Its high thereal stability and resistance to corrosion it appears In sore than 3,000 sanufactured goods In the United States. Estlaates are that at least 30,000,000 tons have been used In construction and aanufacturlng since the year 1900. This common use of asbestos has led to the exposure of allllons of Americans at levels that say have a significant lapact on their health. Today, large numbers of Aserlcans are exposed to asbestos In Industry as well as the environment where It oceurs naturally. Host environmental exposures occurs In our cities, near industrial cosplexes, from soil high in asbestos eontentT in the water, and In the air froa these sources. Therefore, most Americans receive at least soae regular low level exposure throughout their lifetimes. In 1980, Dr. Churg (1) determined that most city dwellers retain a considerable amount of asbestos In their lungs in soae state of clearance. The retained amounts can be In the millions of fibers just from living and working in the city where low level exposures to asbestos Is commonplace. The concerns about the role of asbestos in the development of a lung disease: asbestos!*, began In the United States In the 1930's and progressed slowly as more was learned about the pathogenesis of the disease. Most of 2 the attention was centered on disabled workers with obvious work-related exposure patterns Involving exposure to the raw fibers of the various forms of asbestos used commercially. Few, If any, controls were followed so that time and Intensity factors led to dose levels that precipitated various degrees of asbestosis. This continued until the 1960's when signs of asbestos-related cancers began to reshape thinking and action about the occupational exposures to asbestos. Today, the exposures of workers to asbestos have been markedly reduced through various means of voluntary controls and legislations that led to the first Federal standards In 1972. Since that time the. permissible exposure levels of asbestos have been reduced through the regulatory processes In the United States. In 1964, Marr (2) concluded that asbestos-related disease was an Important problem among Insulators working In Kaval shipyards. His assumptions were correct; however, the methods of assessment weakened the conclusions. Pioneer work was begun at Puget Sound Naval Shipyard (PSNS) In 1965, culminating in a conclusive report of exposure levels and medical findings by Mangold, Beckett ft Bessmer (3.4). Most of the attention was directed at the products and the operations that produced high-level exposures to asbestos workers and associated trades, and because of the large volumes of asbestos used annually In the shipyard'. 'The conclusions were that the threshold limit value (TLV) 3 was still too high at 5 Billions of particles per cubic foot (MFPCF), equivalent to about 50 fibers per cubic centimeter, and that lnteraittent peak exposures were far more important that previously recognized. Both conclusions have been corroborated by sore recent literature. About '1964, Selikoff (5,6) and others reported the association of exposure to asbestos with asbestos-related cancers and the effects of saoklng. ' ' In 1978, Or. Selikoff (7) and a teas of scientists published a protracted study-of asbestos-related diseases whleh defined the latent effects of exposure and probable dose-response relationship based upon tlae and intensity of exposure. The aodel formulated from high level exposures was extrapolated to all levels of exposure however so small. But, J.E. Craighead, et.al. (8). M.R. Beeklake (9) and W.J. Nicholson (10) all raised reasonable questions about the validity of the straight line approach because of the latency factors and ill-defined responses to low level exposure. Nicholson (10) further observed that the long lapse time from exposure to the onset of asbestoala, or asbestos-related cancers, creates difficulties In attempting to establish the true dose-response relationship. And, the diseases today were from decades past when few - measurements of asbestos concentrations in the breathing zone of workers were made, exposures were high, and controls few. Since that time Or. Churg (1) has described the 4 relatively high levels of asbestos fibers In the lungs of city dwellers not occupationally exposed. This suggests a sigmoid, or "S" shaped curve, so often found where a lower no-effect level Is reached. Otherwise, Billions of Americans receiving dally exposures to asbestos from the environment at low levels should show significant asbestos-related disease. They do not. ' Therefore, the assumptions that all levels of exposure have the same risk through the straight line dose-response model Is extreme and without proof. It la based upon extrapolation and assumption. The Occupational Safety and Health Administration (OSHA) used those assumptions in the 1972 Federal regulation for occupational exposure to asbestos (11) and subsequent downward revisions. In addition, they-have made the assumptlorT that all forms of asbestos, namely Chrysotlle, Amoslte, and Croeldollte, and more recently less used commercial forms all produce asbestos-related disease at the same levels of exposure. More recent studies In 1988 by Or. Churg and others (12,13} show that the potency of the various forms of asbestos are different related to the cancer producing effects. However, OSXA treats them alike; as does the Environmental Protection Agency (EPA) for regulatory control purposes. 2. ENVIRONMENTAL EXPOSURES: The amount of environmental exposure to natural forms of asbestos in the United States 5 is substantial. Asbestos, vainly ChrysotiJe, is common to the aabient air in the environment especially near mountainous regions in the United States. There are 22 States with major asbestos outcroppings that contribute substantial amounts of asbestos to the air. water, and the eroded soil. Many major cities, as Seattle, Washington may use drinking water for the population that contains 400,000 to 1,000,000 asbestos fibers per liter of water. Because the asbestos occurring naturally is' ao wide spread on the East and West coast and along the border with Canada, millions of Americans reeelve dally and substantial exposures to asbestos froa birth from these natural sources. The increased activities In cities and the concentration of large numbers of the population on a dally basis causes even further Increases in exposures, some from manmade products .such as clutches or brakes of vehicles. It is not uncommon to find airborne concentrations of asbestos in such communities at levels of about .002 flbers/cc of air, rising to occasional peaks of .02 flbers/cc or more. - - The background levels of natural occurring asbestos in air is so prevalent that the EPA took into account the influence for clearance of school buildings following - an asbestos removal (14). Zt is not uncommon to find the ambient airborne concentrations exceeding those inside office or school buildings. The current-EPA criteria for clearance of a school building following an asbestos removal project 6 is .02 fibers/cc by transmission electron microscopy for total fibers. At that level the EPA considers the building cleared-for occupancy. Doll ft Peto (15), Kelli k Hughes (16), and Hughes k Weill (17) all have made conteaporary predictions of the risk "bf environmental exposures at these levels. Soil and Peto predict one excess death from environmental exposure in a year in the United Kingdom. Such a low level of risk at the known environmental levels in the United Kingdom and the United States would account for the fact that millions of people so exposed do not demonstrate asbestosrelated diseases: suggesting a lower no-effect level* 3. VOLUME OP ASBESTOS USED IN SHIPYARDS: It is important to make a contrast between the discussion of environmental exposures and the amount of asbestos used in a Naval Shipyard in the 1940's during the World War II years. The PlelscherDrinker report on Naval shipyards published in 1946 shows that in those small industrial communities 100,000 to 200,000 pounds of asbestos products would be used eaeh month In ship construction (18). The report made no mention of the volume of asbestos that needed to be removed prior to overhaul or renovation. The amount of material alone sets the conditions for high levels of exposure to workers handling the asbestos under these conditions. About 90k of the products used were amoslte blankets or pads, loose amosite, magnesia block Insulation, and asbestos cements. 7 All of these aaterials were loose, easily broken or eruabled, end handled directly by workers. The potential for high level exposure, especially peaks, is apparent. Few effective control aeasures were In place at that ties largely because the real risk from high level exposures over long periods of time were not realized because of the extreae latency period. 4. EXPOSURES 07 THE CONSTRUCTION AND SHIPYARD TRADES: There are several studies that atteapted to define the occupational exposures to workers In the construction and shipyard trades In the 1960's. They constitute a cross section of the Aaerlcan experience at controlling high level occupational exposures where they were occurring In Industry. In 1970, Mangold, Beckett, and Bessaer (3,4) published a report on exposures to asbestos at Puget Sound Naval Shipyard -showing that 21k of asbestos workers showed pulaonary abnoraallties. They concluded that the TLV of 5 MPPCP was too high, that peaks were laportant, and that changes of work practices were required. The publication contains the levels of exposures recorded for the workers activities. In 1966, W.C. Cooper and L. Baltzer (19) published a siailar study of construction workers In the San Francisco Bay area. About 25* of the construction workers handling asbestos' products and receiving high level exposures showed x-ray changes of the lungs. -They-concluded that the'TLV was too high and needed to be reduced. The types of products and 8 the levels of occupational exposure for the construction workers was recorded. Zn 1971, Gaensler (20) published a study of exposures and medical findings In a private shipyard on the Cast coast. He concluded that exposures were too high and that the TLV should be reduced. A comparison of the asbestos exposures by job are contained In the report. These three studies show that the use of large volumes of asbestos with corresponding high levels of exposure were commonplace among those required to handle or remove It. Sueh substantial levels of exposure are those that account for the asbestos-related diseases following long latency periods. The concentrations are many orders of magnitude above background levels, or environmental exposures. 5. CURRENT ALLOWABLE LEVELS OF EXPOSURE: The American Conference of Governmental Industrial Hygienists (ACGIR) adopted a Threshold Limit Value (TLV) for asbestos In 1946 of 5 millions of partleles per cubic foot of air sampled for an 6 hour time-weighted average workday (TWA). Zt remained In effect until 1969, when It was reduced to 2 MPPCF or 12 flbers/cc. Currently, separate TLV's are published for each type of asbestos used commercially; ' A. Chrysotlle: 2 flbers/cc, 8 hr TWA ,B. Amosite: .5 flbers/cc, 8 hr TWA C. Crocidolite: .2 _fibers/cc,. 8 hr TWA -- D. Other: 2 flbers/cc, 8 hr TWA 9 The current OSHA Federal standard for occupational exposure to asbestos Is .2 flbers/cc for all forms of asbestos used commercially. It makes no distinction between the types of asbestos. The regulation specifies the use of a special technique of air sampling and laboratory analysis by phase contrast microscopy at 400 X magnification (11). The EPA now regulates school clearance following an asbestos removal project to ;01 flbers/cc as determined by transmission electron microscopy, a precise method that measures all asbestos fibers present (14). It is apparent that the ACGIH recommendations do not agree with -the OSHA permissible exposure limit. The EPA clearance ..level Is aimed at public policy for schools where asbestos is managed, or removed. 6. CONTINUING EVALUATIONS: Following control programs In the 1960's and 1970's and more recently those mandated by Federal or State regulations, the overall occupational exposure levels to workers has dropped markedly. Investigatorshave now turned to other sources of asbestos used in industry to determine the contribution to the overall exposure, if any. -* In the 1960's the major goal was to reduce the - 10 high level exposures occurring from highly friable asbestos materials used in large volume in construction and in ahlpyards. The saall voluae products and those that were encapsulated were not considered because of the saall contribution to the overall exposure pattern (3,4). And, because tests revealed that the low ealsslons were obscured by the high background levels froa other highly . friable products (3,4,19,20). Most of the data In the earlier reports evaluate processes which Include the Influence of all sources of asbestos that Bay be present. It Is difficult to differentiate the contributions of the various types of asbestos products which were being used at the sane time, or In near proximity to each other. 7. U.S. NAVY CASKET REPORT: In 1978, the U.S. Department of the Navy (21), as part of a continuing evaluation program, set about evaluating the asbestos exposures to workers froa the storage, handling, and processing gaskets of all kinds In Naval shipyards. The.evaluation Is Important because there are only a few such publications that identify and estimate the occupational exposure to gasket materials in shipyards, the report ' concludes that even the simplest of general housekeeping controls or work practices are sufficient to maintain occupational exposures at acceptable levels. In fact, most of the exposures were found to be less than .1 flber/ce 11 for an 8 hour TWA, a level at which aedlcal examinations are not required according to the current Federal standard for asbestos. The 1978 U.S. Navy report did achieve the Intended purpose to determine the exposure to any and all asbestos In the_breathing rone of workers but does not deteralne the actual contribution from the gaskets alone. The breathing zone air samples were collected for various foras of'gasket processing In soae work areas under uncontrolled conditions and In the presence of contaainatlon froa other asbestos products. The results are actually the contribution froa the gaskets, background levels, and contaainatlon froa other asbestos produets. They do not reflect the aetual contribution froa the gaskets. Because the airborne concentrations were extreaely low, often .01 flbers/cc or less, the potential for contaainatlon Is certain and cause a major contribution to the reported values for gasket processing. Many of the reported values reflect the actual exposure tlae; not an 8 hour tiae-weighted average. The 8 hour TWA measurement or calculation Is necessary to be able to compare the values to the current Federal standard. Short term peak exposures measured In this way will nearly always be greater than the 8 hr TWA, often by several orders of magnitude. While the 1978 U.S. Navy-report achieved the Intent there are several objections In the use of the 12 J* data to reflect the actual contribution from gaskets alone. They are; A. Short term peak exposures are reported that cannot be directly coopered to the 0 hour TWA of the Federal standards. B*. Ko attempt was Bade to control or faetor the contributions of contamination from the results. The contamination levels may even have exceeded the ' actual contribution from the gaskets processed. C. The data was Intended to determine the overall peak exposures from unit operations that Included all asbestos contributions. ' The small contributions from gaskets are confounded or obscured by high background contamination levels where the gaskets- were processed, contaminated clothing, and atmospheric pollution. 8. VERIFICATION OF THE 1970 O.S. HAW STUDY: Because of the objections offered above, the U.S. Navy report could not be used with accuracy to reflect the actual contribution of gaskets alone. Zn 1902, the Garlock, Inc. commissioned C.A. Mangold (22) to repeat the U.S. Navy investigation on gaskets as nearly as possible and to take into account the effects of contamination in order to sake estimates of the'actual contribution of gaskets to the occupational exposure of a worker handling or 13 processing then. In addition, the data was to reflect the 8 hour time-weighted average work day for direct comparison to the existing Federal standards for asbestos. Samples of the ambient air were eollected In various cities to show the apparent level of natural and manmade asbestos fiber pollution. The effects of contaminated elothlng that a worker may wear were evaluated to determine the contributions. All sources of contribution were ' considered to control or factor those background levels that were not part of the contributions from the processing of the gaskets. After the background levels were meesured orcontrolled, the data showed that hardpressed or encapsulated Garloek, Inc. gasket produets released Insignificant levels into the breathing zone of workers processing gaskets in the same manner as conducted in Naval shipyards. The actual contribution for the processing of gaskets averaged .02 flbers/ee for mm S hour when the effeets of contamination from other sources or asbestos products were controlled. The peak background levels of ambient air-in Industrial areas, or In cities on warm summer days may reaeh these levels. This verification of the U.S. Navy report revealed ' that when the contamination was factored or controlled the values for the actual contribution from gaskets were about 50k of those reported by the U.S. Navy. The study conducted by Mangold (23) more appropriately 14 A reflect# the actual contribution froa handling or processing encapsulated gasket for an 8 hour tine-weighted average work day. The overall average of .02 flbers/ec is l/10th of the current Federal standard for occupational exposure to asbestos fibers In air. 9. THE DILEMMA: The verification of the 1978 O.S. Navy report ahows that hardpressed or encapsulated gaskets actually contribute negligible aaounts of asbestos when handled or processed as in Industry or In shipyard. Negligible exposures present a negligible risk. The risk is in the saae Magnitude-as some environmental exposures to the population at large. However, additional measurements under highly controlled conditions, are needed because; A. Some workmen describe specific aethods of handling, processing or removing gaskets froa machinery or piping that were not evaluated in the 1978 U.S. Navy report or the subsequent verification. Some are not standard operating practices expected of workmen experienced in the handling, processing or removal of encapsulated gaskets froa machinery or piping. . ' B. The 1978 O.S. Navy report and the 1982 verification contains the effects of levels of contamination that are in the same range as.the expected actual contribution of' airborne asbestos fibers froa the gasket alone. Therefore, IS & the results will be skewed upward by that contamination contribution. Better definition is needed where the effects of other -asbestos products do not Interfere with the tests. C. Aabient concentrations of chrysotlle asbestos fibers that occur naturally fron soil and water, and from aansade products add some contribution to the measurements of the emission from gaskets. The contributions can be substantial and in the same range as the expected actual ealssloh froa the gaskets being handled, processed or raaoved. D. Hew analytical aethods that were not available or practical for the U.S. Navy report in 1978 or the verification in 1982, are now readily available and within econoaic practically. These aethods can provide a more precise exaalnation of the actual release of fibers froa encapsulated gaskets. - E. The- new analytical aethods have a auch.lower Halt of detection that those used In the 1978 and 1982 reports. The aethods now available can not only determine the total nuaber of fibers present, but determine the types of fibers they are. This is valuable because the ehryaotHm asbestos Is used In encapsulated gaskets. p. The new analytical aethods can sake a direct coaparison to the older Phase Contrast Microscopy (PCM) - aethod specified in the Pederal standard through the use of Scanning Transmission Electron Microscopy (STEM). It can verify the PCM aethod which is easily Influenced by other non-asbestos fibers, If they are present. - 26 G. A better definition of by-stander exposure was needed, .that Is, the levels of exposure of a worker 5 or 10 feet away froa another worker making, Installing, or removing encapsulated gaskets. 10. EXPERIMENTAL DESIGN: . Although the 1978 D.S. Navy report and the 1982 verification show that only negligible amounts of asbestos fibers are released froa the handling or processing of gaskets, additional measurements are needed to utilize the new analytical methods, to better control the effects of ambient or manmade contamination, and to determine the actual contributions from the gaskets handled In the ways described by some workmen. And, the by-stander exposures froa those selected processes. A clean room condition was needed for the testing In order to accurately measure the low level release of chrysotlle asbestos fibers froa the encapsulated gasket materials processed or removed froa flanges. Sines the emissions were expected to be near the Halt of detection of' phase contrast microscopy methods used, special precautions were taken to control potential contamination. A new metal building was leased In Kent, Washington 17 where electron microscopy samples showed that the amount of natural ambient asbestos was .002 flbers/ec or Jess for all sizes of .fibers. The nsw building was selected to ensure that accuaulation of dust, or previous asbestos insulation contamination was not present. Inside the building, an enclosure of polyethylene plastic was constructed that measured 20 feet by 20 feet and 10 feet high, or 4000 cubic feet. This represents a snail coapartnent or room where sueh work aay be done in Industry or aboard ship and that aay be occupied by a by stander. The celling and floor was covered with polyethylene plastic and all the edges were sealed. The only entry was a specially designed flap door that would remain sealed during testing. ' A clean work bench was placed in the center of the enclosure.-The gaskets were processed on the bench according to the descriptions given by some workmen. Sample locations were assembled on the points of the compass at head height inside the room. The saaple stations were located 5 and 10 feet away froa the work bench in the center of the room. The sample cassettes for analysis by phase contrast microscopy and scanning electron microscopy were placed at the saaple stations. Air was drawn through the special filters in the cassettes by electrically operated high volume air samplers. The volumes of air were measured by recording the flow rates~wlth~~a class A rotoaeter and recording the amount of time the samples were collected. Kine 18 PCM and 8 STEM samples were collected for each test. One PCM was worn by the operator at the work bench to record the breathing zone exposure. The other sample stations provided a preponderance of data and simulated by-stander exposures at 5 and 10 feet away from the gasket processing. Samples of gasket material containing chrysotlle asbestos were obtained from the manufacturer for processing. And, piping and valves were obtained from aC.S. Vaval vessel, the OSN Gypsy (ARSD-1) which was scrapped In Portland, Oregon. She was built In 1944, served In the Pacific Theatre during World War II, and was decommissioned in the 1950's. ' Some of the flanges had never been opened since the vessel was built. All of the residual asbestos Insulation on the outside of the piping was removed to prevent contamination when the gaskets were removed from the flanges. Plastic Impregnated protective clothing (TYVEC) was worn by the operator to control the potential release of non-asbestos fibers from street clothing, and dust from shoes. - The tests were conducted over an 8 hour time-weighted work day. This Is necessary to develop data that can be directly compared to the Federal standard for occupational ' exposure to asbestos. It Is Inappropriate to attempt to compare peak exposures to the Federal standard. Following the tests, the sample cassettes were removed and delivered to ESSTEK, a highly qualified asbestos 19 * analytical laboratory capable of conducting phase contrast microscopy (PCM) according to Appendix A. of the Federal asbestos standard, and transmission electron microscopy (TEM). Special arrangements were Bade to directly compare the results by PCM with that obtained by TEM. The PCM analysis is subject to influence by non-asbestos fibers that nay be present. But, the TEM aethod is highly specific, determines all asbestos fibers present, identifies the type of fiber present, and has a very low limit of detection about .002 structures/ec (approximately equal to flbers/cc). Arrangement were made to have at least 75k of the PCM samples blind counted. This means at least two qualified asbestos counters would make a determination without knowing the result of the other. The results are then compared. This minimizes the potential for counting errors. The -PCM and the TEM samples collected at each sample location at the same time and filtering about the same volume of air, were compared as duplicates. This provides two separate determinations with highly specific aethods at the same location and gives a high degree of confidence that each determination is comparative. The results and conclusions for the tests conducted are found in paragraphs 12 and 13. 20 II. REFERENCES: I. A. Churg and M. Warnock, "Asbestos Fiber* In the General Population", As. Rev. Reap. Disease, Vol 122 (1980) 2^ W.T. Marr, "Asbestos Exposure During Naval Vessel Overhaul, Aa. Ind. Hyg. J. 25:264 (Kay-June 1964) 3. C.A. Mangold, R.R. Beckett, D.J. Bessaer, "Asbestos Exposure and Pulaonary X-Ray Changes to Pipe Coverers and Insulators at Puget Sound Naval Shipyard," PSNS, Dept, of Navy, Brenerton, WA. (August 1966) - 4. C.A. Mangold, R.R. Beekett, D. J. Bessaer, "Asbestos Exposure and Control-Puget Sound Naval Shipyard," O.S. Dept, of Navy, (May 1970) 5. I.J. Sellkoff, J. Churg, E.C. Baaaons, "Asbestos Exposure and Neoplasia", JAMA 188:22 (1964) 6. I.J. Sellkoff, J. Churg, E.C. Baaaons, "Relation Between Exposure to Asbestos and Mesothelloaa", N. Eng. J. Med. 272:560-565 (1965) 7. I.J. Sellkoff, M.D., "Disability Coapensatlon for Asbestos-Associated Disease in the United States", Env. Sci. Lab, Mt. Sinai Hospital, City Univ., N.Y. (Report to U.S. 21 Dept of Labor - (June 1962) 6. J.E. Craighead, B.T. Mosssan, "The Pathogenesis of Asbestos-Associated Diseases", N. Eng. J. Med., 306 (June 17, 19B2) ' 9. M.R. Becklake, "Exposure to Asbestos and Busan Disease", N. Eng. J. Med., 306, (June 17, 1982) 10. W.J. Nicholson, A. M. Ranger, Z.J. Selikoff, "Epidemiological Evidence on Asbestos", Proceedings of a Workshop on Asbestos Definitions and Measurement Methods. (July 1977) Gaithersburg, MD, U.S. Dept. Cosserce Pub. # 506 (Nov 1978) 11. Federal Asbestos Standard: 29 CFR 1910.1001 and 1926.58; Occupational Exposure to Asbestos, Tresollte, Anthophylllte, and Aetlnollte, Final Rules, (June 20, 1986) 12. Dr. Andrew Churg, "Chrysotile, Tresollte and Malignant Mesothellosa in Man", Chest 93(3): 621:628 (1988) 13. A. Churg and L. De Paoli, "Clearance of Chrysotile Asbestos froa Busan Lung", Experlaental Lung Research, 14(5): 567-574 (1988) 14. Environmental Protection Agency: 40 CFR, Part 763, 22 4* Asbestos-Containing Materials in Schools; Final Rule and Notice, (Oct 30, 1987) 15. R. Soil and J. Peto, "Asbestos; Effects on Health of Exposure to Asbestos", London, Her Majesty's Stationery Office, (1986) 16. H. Weill and J. Hughes, "Asbestos as a Public Health Risk: Disease and Policy", Ann Rev Pub Hlth, 7, (1986) 17. J. Hughes and B. Weill, Asbestos ExposureQuantitative Assessment of Risk", Am Rev Resp Dis (1986) IB. W.E. Fleischer, F.J. Viles', R.L. Cade, and Phillip Drinker, "A Health Survey of Pipe Covering Operations in Constructing Naval Vessels", J. Ind. Hyg. Tox. 28:9 (Jan 1946) 19. J.L. Baltzer and W. Clark Cooper,M.D.," The Work Envlronaent of Insulating Workers, As. Ind. Hyg. Assoc., 29:222 (May-Jun 1968) 20. R.L.H. Murphy, Jr.M.D., B. Ferris, W. Burgess, J. Worcester, E.A. Gaensler, M.D., "Effects of Low Concentrations of Asbestos: Clinical, Environmental, Radiological, and Epidemiologic Observations in Shipyard Pipe Coverers and Controls", N. Eng. J. Med., 23:285, 23 (December 1971) 21:. L.R. Liukonen, JC.R. Still, R.R. Beckett, "A*be*to* Exposure from Casket Operations", U.S. Dept, of Wavy, Bremerton, Washington ( Kay 1978) 22. C.A. Mangold, "The Actual Contribution of Garloek Asbestos Gasket Materials to the Occupational Exposure of Asbestos Workers", October 1982, Bellevue, Washington. 24 RESULTS AND CONCLUSIONS: Workmen required to open flanges of pipe and machinery containing asbestos gasket materials must first determine how to move the piping, then unbolt the flanges, separate the flange faces, then remove the gasket. The flange faces are then cleaned and a new pre-cut gasket or one prepared at that location Is Inserted and the process reversed. Normally gaskets are not removed from flanges or machinery unless there is a reason such as overhaul, leaking piping or surfaces, or removal of machinery. When the gaskets are removed many are released from the flange faces intact, while others may leave some residual of the encapsulated gasket stuck to the edges. The residual Is removed with a sharp Instrument and a new gasket Inserted. This evaluation Involved the opening of flanges taken from a U.S~ Navy vessel, the USN Gypsy (ARSD-1), which was built in 1944, saw service In the Pacific Theatre in World War II and was decommissioned in the 1950's. Some of the gaskets in the piping flanges removed for examination may have been in place up to 40 years. The bolts were removed from the flanges of various sizes and a sharp instrument used to separate the flange faces. At least 8 flanges were opened during the 8 hour sampling period to determine the 8 hour time weighted average of a workman opening piping during a work day. Not all of the gaskets removed from the flanges bore the Garlock logo, but all were similar in texture and 25 contained chrysotlle asbestos. The conduct of opening flanges containing asbestos gaskets-inside a clean room with a low background and low anbient levels in the air allows a realistic measurement of the exposure pattern of the operator and any by-stander near Ihe operator. The 8 sampling stations situated around the room provided sufficient data to establish those ranges of by-stander exposure. . The attached data sheets show that; 1. The electron microscopy methods for total chrysotlle fibers in samples collected at each of 8 sample stations averaged .002 structures/cc.'The structures/cc are ' approximately equal to fibers/cc. This method determined all of the chrysotlle present regardless of fiber size. There Is no total asbestos fiber standard. 2. The electron microscopy analyses of the samples for fibers greater than 5 micrometers in length and .25 micrometers in diameter is a method of comparison to the phase contrast microscopy method specified in the Federal standard. In this way the phase contrast results can be verified. The results show that no fibers of chrysotlle were found greater than 5 micrometers in length above the lower level of detection of .002 structures/cc. 3. The phase contrast microscopy results for the 8 sample stations averaged .001 flbers/ec or .slightlyjgreater, but not greater than .002 fibers/cc. This would represent the exposure pattern of a by-stander in the room with the 26 & operator. The exposure pattern of the operator opening flanges and removing the asbestos gaskets was .005 flbers/ec, >5 tun in length. The difference between these results and the electron microscopy results is likely due to some other non-asbestos fibers that must be counted according to the analytical rules. However, the values are quite low and are essentially in the same range. . All of the results represent an 8 hour time-weighted average for direct comparison to the Federal standard of .2 fibers/cc, >5 um in length. The exposure pattern is a fraction of the Federal standard as expected. The hard pressed, encapsulated gaskets releases insignificant amounts of chrysotile asbestos during the opening and removing of gaskets from flange faces. The precise electron microscopy methods verified and corroborated that exposures are'negllglble in terms of the current Federal standard of .2 flbers/cc. >5ua in length. 27 low* LOCATION OF SAMPLE STATIONS IN THE ASBESTOS FIBER FREE ENCLOSURE ^f/VT*y ^ hxP I Ohl # 5vu # 5H BENCH 5$ 0 5 lt$* Enclosure Height * 101 20 IDE. l SET 7 "Opening Flanges1 I TRANSMISSION ELECTRON MICROSCOPY . AIR SAMPLE ANALYSIS RESULTS CLIENT: Carl A. Mangold, CIN PROJECT: Carlock Research REPORT I: 112057 PACE: 3 of 13 CLIENT SAMPLE ID ESS* TEK ID CONCENTRATION CHRYSOTILE ALL SIZES STRUCTURE SIZE CHRYSOTILE COUNTED LENGTH >5.0 US STRUCTURES (S/CC) DIAMETER >.25 OB CONCENTRATION LENGTH >5.0 DIAMETER >.25 S/cc T5N-33 812057 T5E-34 812058 T5S-35 812059 T5W-36 812060 T10N-37 812061 T10E-38 812062 T10S-39 812063 T10N-40 81i064 LAB BLANK NSD NSD NSD 1 2 NSD NSD NSD BLD * BLD BLD 0.002 0.004 BLD BLD BLD NSD X_- , OO*2L NSD NSD NSD NSD 1 NSD NSD NSD 0.000 0.000 0.000 0.000 0.002 0.000 0.000 0.000 ---------- ^ CCO Analytical Sensitivity 0.002 S/cc NSD - No Structures Detected BLD - Belov Level of Detection S/cc - Structures per cc fibers per cc BLP * ,00 2.^/cc. I I AIR SAMPLE ANALYSIS REPORT CLUNT: Carl A. Mangold, C.I.H. PROJECT: Garlcck Research - Sec V SAMPLE LOCATIONS (continued) i RETORT I: 50-128140 RAGS 2 of 2 Sarple #128144 was taken north lOfc at Maple station. Staple #128145 was taken east lOfc at sample station. Staple #128145 was taken south 10ft at aasple station. Sacple #128147 was taken west 10ft at sample station. . Sanple #128148 was a perscra! sasple in breathing zone of operator. ' Staple #128148 was submitted as a blank. 77* sasples analyzed in this report were provided by third parties not subject to control by Br/ircmental Safety Systems, Inc. (ESS) or its affiliates. Ctnaaquently, the results presented represent microscopic examinations in ESS laboratoiy facilities and ESS makes ao representation as to sasple collection techniques or procedures. Analysis was perfonned using phase contrast microscopy under the guidelines of KIQSH method #7400-A. * A minirum of ten fibers per 100 fields is needed for reliable quantification. Sacples with less than 10 fibers per 100 fields are reported as less than (<} the quantifiestion limit. ' * toounta of nerr-fibrbus material are determined using charts for estisating carpositicn fran ths Journal of Sedimentary Petrology (v. 25, pp. 229-234, 1955). Amounts reported reflect nen-fibrous material density on sarple filter only. Legend: T * Trace (less than 1%), VL Very Low (2-5%), L * Low (5-15%), M Moderate (15-25%), H High (25-40%), VH Very High (greater than 40%). Microscope Field Area * 0.00785 am? 2 Bqsosed Filter Area 385.0 nm - Analyst (s) - HAL Environmental Safety Systems, Inc Gateway Corporate Park, Bldg. 5 12822 Cateway Drive Seattle, Washington HIM (206) 24X573 AIR SAMPLE JMIXSZS REPORT CLIENTi Carl A. Mangold, C.I.H. 3033 170&h Place SE Bellevue, WA 98008 PROJECT: Garlock Research - Set V Opening Flanges REPORT it 50-128140 REPORT SAZSt 12-09-88 PAGE 1 of 2 DAIS RBngVEPt 12-02-88 PO it Kmr Gives ff.TPVP SAMPLE ZD ESS ZD SAMPLE SAMPLE DAZE VOL CL) TIBER rmo BLANK Q7T FIBERS BEGEM) CDCNT croNT /100 FLDS per ac * MAI * PSN-33 128140 12-01-88 5760 36.5 100 P5E-34 128141 12-01-88 5760 15.5 100 P5S-35 128142 12-01-88 5760 22.5 100 P5W-36 128143 12-01-88 5520 14.0 100 P10N-37 128144 12-01-88 5760 8.5 100 P10E-38 128145 12-01-88 5760 10.5 100 P10S-39 128146 12-01-88 5520 16.0 100- P10W-40 . 128147 12-01-88 PP-5(f/r*4**f) 128148 12-01-88 5760 1080 15.5 6.0 100 100 P-BLK-5 128149 12-01-88 0 3.5 100 SAMPLE LCCATZCHS; Sanple #128140 was taken north 5ft at sasple station. 3.50 3.50 0.003 VH 0.001 VH 3.50 0.002 VH 3.50 0.001 VH 3.50 < 0.001 VH 3.50 < 0.001 VH 3.50 0.001 VH 3.50 0.001 VH f H3.50 < 0.005 N/A BLANK " ci ^ Sanple #128141 was taken east 5ft -at sanple .station. - - Sacple #128142 was taken south 5ft at sanple station. Sarple #128143 was takes test 5ft at sanple statics. Butt Sampling Air Monitoring * Analy$ii Asbestos Abatement Equipment & Supplies --