Document EdzOnKZM2mOrQqp0mvNjeq1jx

FILE NAME Manville JMA DATE 1977 July 29 DOC JMA382 DOCUMENT DESCRIPTION Federal Register - Testimony Regarding 16 CFR Parts & Proposal to Ban Certain Pactching Compounds 489 TESTIMONY REGARDING 16 CFR Parts 1304 and 1305 RESPIRABLE FORM ASBESTOS Proposal to Ban Certain Patching Compounds and Artificial Emberizing Materials Embers and Ash As Published in the FEDERAL REGISTER Vol 42 No. 146 - Friday July 29 1977 Presented by Harrison B. Rhodes Union Carbide Corporation Metals Division Niagara Falls New York 14302 August 15 1977 My name is Harrison B. Rhodes and I am speaking on behalf of the Union Carbide Corporation where I hold the position of Technology Manager in the Calidria Asbestos Department My education is in the fielodf Chemical Engineering where I hold the degree of Dr. of Science from Columbia University For the past four years my assignment has been in the area of asbestos health and regulatory matters and has also included research on monitoring techniques I am currently serving the Asbestos Information Association America as Chairman of the Standards and Technical Committee Union Carbide Corporation has been actively engaged since 1963 in the mining and milling of asbestos ore at facilities in central California The asbestos fiber produced is marketed throughout the United States and in many foreign countries One of the principal applications for this asbestos in this country has been in joint compounds We do not ourselves manufacture such compounds however nor do we manufacture any other containing finished products As the Commissioners are well aware there has been a tremendous flood of paper generated in relation to the asbestos regulatory matters under consideration here We believe that several crucial issues have been lost in the flood and would like to take the opportunity today to address these issues as follows 1. A look at all of the commercial and consumer exposure data available today including some recent consumer tests and also some OSHA compliance inspection results 2 An examination of the risk estimation model proposed by Dr. Bayard of the CPSC staff in terms of actual consumer exposure -2- 3. A discussion of the elimination or reduction of unreasonable risk of injury as required by the statute and the absolute zero risk regulatory approach that is advocated by the petitioners 4 The direction of your attention to the fact that asbestos of one type or another is present throughout the air water and earth of this planet and the overwhelming consequences of a ban of ubiquitous material such as this without a precise definition of what is banned a well specified analytical procedure and some allowable levels other than zero 5. The presentation of a suggested alternative approach to protect the consumer from unreasonable risk of injury which is more realistic more workable and more enforceable than the proposed total ban It should be emphasized that this discussion will deal directly with and be presented in terms of joint compounds Spackling compounds are similar in composition and use but are applied in so much smaller amounts that the potential for significant exposure is virtually existent Emberizing kits are outside the field of our expertise and will not be considered Gypsum wallboard was developed around 1880-1900 It did not come into wide usage until World War II when the need for houses and other buildings made this quicker less complex construction method very popular Usage has grown substantially since that time and drywall construction is now used in a majority of residential construction and in a wide variety of commercial and public buildings Initially ordinary plaster was used to embed and cover the tape to make the joint between the boards but in the mid 40's specially formulated -3- ' dry mixtures with casein as the binder were introduced These mixtures typically contained 10-15 asbestos We have been told that the plaster of that time also contained asbestos Ready i.e. wet compounds or mud were introduced in the mid 50's and were in broad general use by 1960. The asbestos content of muds in general dropped during the 70's to approximately the range of 2-7 joint compounds containing asbestos have thus been in widespread use for 30-35 years Over the first 15 years of this period the main material used was provided dry and contained relatively high levels of asbestos i.e. 10-15 The Commission's consultant A. T. Kearney Inc. estimates that today's annual value of shipments of patching compounds is 80 million dollars At an average price of 4.50 per can This is equivalent to about 18 million cans The formulations we have seen cost about 20-30 more per can in raw material costs to replace asbestos so that the added burden just to cover raw materials cost is about 4.5 million dollars annually This cost plus any percentage markups used would be added to the cost of the structure and would carry the normal financing charges over the life of the indebtedness It should also be noted that about 10,000 tons per year of asbestos with a product value of about one million dollars were used in this application prior to the decline that has resulted from actions of a variety of governmental agencies We believe that the total of 5.5 million dollars annually presents a reasonably reliable minimum estimate of the direct economic effects of the replacement of asbestos in joint compounds The added effect of the poor performance of many of the asbestos free muds has not been considered In the assessment of the risk that needs to be related to this cost burden it is important to have a reliable estimate of the level of consumer exposure All of the available information on exposure has been assembled and -4- is documented and discussed in detail in an Appendix to this presentation which will be submitted prior to the August 29 1977 deadline for written comments Only the key results will be summarized here The data presented are contained in five reports 1. The tests conducted by Rohl et al at one location in New York NY This is the data cited by the petitioners A survey of a variety of sanding conditions made by Rhodes and Ingalls and cited extensively by the Asbestos Information Association America in their response to the petition Data from State and Federal OSHA compliance inspections compiled by Equitable Environmental Health Incorporated as part of a study of asbestos exposure in the construction industry A report submitted to the CPSC by Union Carbide Corporation on July 14 1977 covering consumer exposure during a typical spackling and a moderate size drywall installation operation A study by Union Carbide Corporation which has just been finished on another consumer installation of drywall in a large room including the ceiling The results of this survey are summarized in the two figures you are now receiving Figure 1 shows along the vertical axis the airborne asbestos concentration in fibers per cubic centimeter longer than 5 micrometers that occurred in the breathing zone of the operator during the sanding opera- tion Usually a number of samples were collected at each location The dark bar shows the range of concentrations found with the arithmetic average of all samples indicated by the arrow 1. Rohl et al Science Volume 189 August 15 1975 p 552 2. G.D.C.I. Drywall February 1976 -5- The data on the left are those of Rohl et al that were cited in support of the petition These were obtained in one test in New York City Note that an exposure of 20 fibers for four days was used by Dr. Bayard in his projection of risk to be discussed later The next group of results were obtained by the Union Carbide Corporation in a survey of commercial operations in eight different cities Results range from about 0.2 to 3 fibers These fiber counts have been spot checked blind by two other laboratories The EEH and OSHA compliance data shown next fall in the same range as those of Union Carbide The consumer data are shown on the far right The first case is for extensive spackling and the installation of three panels of drywall The second is for three walls and the ceiling of a large basement recreation room This latter mud contained 2.6 asbestos by weight on a dry basis Exposures in these tests were only 0.2 to 1.0 fibers 5...which correspond roughly to the lower end of the range found for commercial use Two other operations in joint installation present the possibility of exposure to form asbestos fiber the addition of dry powder product to water and the cleanup after sanding Data for these operations are shown in Figure 2. Here in order to get the Rohl et al data on the graph it was necessary to run the scale from zero to sixty instead of zero to twenty as in the previous figure Otherwise the graph follows the same format and shows a very similar pattern The Rohl et al data are far higher than the OSHA results and the consumer values are below or in the lower end of the range found for commercial use It is very important to understand that all of the concentrations shown occurred during the active pursuit of the particular operation i.e. sanding wet or cleanup These operations generally take place for a moderate portion . of the day with concentrations at much lower values for the rest of the 8 hour -0- period Eight weighted average exposures were calculated for the two consumer installations and the highest exposure found was 0.2 fiber 5u for two days while containing dust was being generated One of your staff members Dr. Stephen Bayard has developed a model to estimate the risk of respiratory cancer from low level exposure to asbestos from taping compounds This model is patterned on that described in a paper by Enterline and Henderson 2 except that Dr. Bayard has made an assumption that the effect of dose is cumulative This builds a geometric increase in risk into the model We question whether there is any basis for this assumption but do not feel that this is an appropriate place to debate the issue It is of more interest to use this model which is heavily biased toward predicting a high risk with the highest exposure just noted for consumer use i.e. 0.2 fiber TWA for two days of operation Following Dr. Bayard's directions in page 3 Part C of the reference cited for the highest weighted average of 0.2 fibers for two days found for the consumer applications we obtain an annual exposure of 0.004 fibers per day for one year a mean latent period to tumor of 621 years and zero deaths of asbestos induced cancer in the year period considered If the period examined is extended to 100 years the number of deaths predicted would be 0.000003 which is still far less than a single death These estimates are probably on the high side due to assumptions used in the model but since an exposure of 0.004 fibers is indistinguishable from background the values found not unreasonable It is also instructive to point out that if we assume an exposure of 5 fibers for full hour days which is well above that found in commercial use the yearly rate becomes 0.1 fiber This yields a median time to tumor of 212.5 years and an asbestos induced cancer estimate of 0.02 deaths We question whether these are the unreasonable risks referred to in the statute 1. Memorandum to Dan Clay dated June 3 1977 2. Presented at Pinehurst NC March 12 1976 -7- Let us now relate this risk to the proposed ban of consumer patching compounds containing respirable form asbestos under Sections 8 and 9 of the Consumer Product Safety Act To quote Section 8 Sec 8. Whenever the Commission finds that-- 1 a consumer product is being or will be distributed in commerce and such consumer product presents an unreasonable risk of injury and 2 no feasible consumer product safety standard under this Act would adequately protect the public from the unreasonable risk of injury associated with such product the Commission may propose and in accordance with section 9 promulgate a rule declaring such product a banned hazardous product Emphasis added And from Section 9 Paragraph 2 c 2 The Commission shall not promulgate a consumer product safety rule unless it finds and includes such finding in the rule A that the rule including its effective date is reasonably necessary to eliminate or reduce an unreasonable risk of injury associated with such product B that the promulgation of the rule is in the public interest and C in the case of a rule declaring the product a banned hazardous product that no feasible consumer product safety standard under this Act would adequately protect the public from the unreasonable risk of injury associated with such product Emphasis added -8- Note particularly the repeated use of the words unreasonable risk and the requirement to eliminate or reduce unreasonable risk not to make this risk zero The Act makes it quite clear that the intent is not the total elimination of all risk but of unreasonable risk and it delegates to the Commission the complex and searching problem of deciding what is reasonable The comments of your own staff on the strength of the evidence used to support the ban is well summarized by three short quotations from the record The petitioners believe that high quantities of asbestos fibers remain in the air after these products are sanded and the fibers substantially increase the risk of mesothelioma and 1 lung cancer The petitioners have addressed problems which arise from being exposed to asbestos fibers occupationally and environ- mentally However they have not cited any concrete evidence of the hazard which is tied directly to the products for which they seek a ban It merely cited the fact that these products do contain asbestos fibers and they have cited the fact that asbestos fibers in other situations have been linked to lung disease We question whether the evidence presented in the petition is sufficient to show that these substances may cause substantial personal injury or substantial illness during or as 2 handloriunsge Emphasis added 1 CFR Vol 42 No. 146 - Friday July 29 1977 p 38790 2 Letter of July 11 1976 from Charles M. Jacobson BCMI to Francine Shacter TAD OSCA -9- The instances of single or short exposure to asbestos cited in the petition can be taken as evidence of a possible but not necessarily probable effect relationship How- ever by themselves they would not stand up to statistical scrutiny in predicting a correlation between brief exposure to asbestos and the later development of cancer caused by such 3 exposure Emphasis added Substantial evidence has been presented here that the commercial use data upon which the petitioners based their allegations is substantially higher than that of all other investigators including OSHA compliance inspections It has also been shown that consumer exposures are low of short duration and when averaged over a year or more are not distinguishable from ambient background We know of no evidence that such casual low exposure represents any hazard so that the question becomes one of a banning action based on the existence of a possible but not proven risk which if it exists at all differs only slightly from zero You are probably aware that this question of the regulation of carcinogens is a major issue today before virtually all of the governmental regulatory agencies The FDA saccharin ban has received wide publicity and OSHA is deeply involved with a proposal for a generic regulation approach to carcinogens and hearings on benzene are now in progress All of this activity does not help to find answers to our immediate problem but we are at least in good company The problem we face originates in the called hit theory of carcinogenisis In simplest outline this theory holds that 3 Briefing Package February 2 1977 presented to the Commission by Fracine Shacter -10- 1. A single molecule of a carcinogen is capable of causing cancer in a particularly susceptible person 2 If enough people are exposed the susceptible person or small number of such persons will contract cancer 3 It follows therefore that there is no absolutely safe or zero risk level for a carcinogen and such a material should depending on the statutory authority of the agency involved be banned severely restricted replaced controlled to the limits of detection etc. It is useful to examine this theory in the light of where there is general agreement and where responsible opinions diverge We believe that virtually all medical authorities would agree 1. That there is a wide range of dosages for a carcinogen where a response relationship exists The larger the dose the greater percentage of these exposed contract cancer and vice versa 2. In exposed populations even at substantial exposure levels large proportions of those exposed do not contract cancer 3. As the dosage goes down the average time to the appearance of a tumor increases This principle was illustrated by the extrapolation formula of Enterline and the Bayard modification discussed previously The medical disagreement occurs over what happens as the dosage is decreased to very low levels There is one school of thought and this is embraced by most of the regulatory agencies that no completely safe level exists There are other responsible authorities who contend that a dosage level is -11- reached where the body's defense mechanisms can effectively combat the altered cells and a cancerous growth does not occur Supporters of this position cite the low level presence of certain metals and hormones that are essential to the human body in trace amounts but at higher levels are carcinogens Unfortunately there is no way to demonstrate the correctness of either view since there is a background level of cancer in both man and experimental animal As the dosage and the corresponding number of cancers decreases one point of view is that the occasional cancer from the specific agent still occurs but cannot be distinguished from the background while the other is that the added cases do not occur These views can be partially resolved with the model of Enterline discussed previously i.e. a very low exposure may cause a cancer but the time to tumor is 150 years for example With an expected life span of 70 years this for all practical purposes is a safe threshold exposure at least until life expectancy approaches 150 years Since there is no provable scientific answer to this risk question we are really left with a political rather than a scientific decision to consider The fundamental question then is whether a total absence of risk approach to regulation is appropriate or more particularly will be acceptable to society In our lives we undergo a succession of risks some knowingly and some unknowingly The American people have always indicated a willingness to take risks as evidenced by such things as the widespread use of the automobile smoking alcohol improper diet and even the home as it is today We believe that the zero risk concept when it begins to impact on jobs and the way of life of a substantial number of people will not be acceptable and will have to be modified to balance risks against benefits in a realistic fashion This sort of balance rather than regulation by cliche its a carcinogen so ban it should be applied here The benefits from the continued use of asbestos in joint compounds is substantial and the risk is either zero or so small it cannot be distinguished from zero This finishes the benefit discussion and I would like to con- clude this presentation by pointing out certain practical aspects of enforce- ment of the ban as presently proposed in the Federal Register These questions were discussed at great length and generally were not solved at the recent meeting in Gaithersburg MD conducted by the National Bureau of Standards Since several members of your staff were present at this meeting they will only be indicated briefly Since the promulgation of the OSHA asbestos regulations in 1972 there has been a continuing debate on what is asbestos and what is an asbestos fiber Asbestos when narrowly defined in a way that will satisfy the most precise minerologists is ubiquitous in the atmosphere although generally it occurs at very low but not zero concentrations When the definition is broadened to include all amphibole chips which are longer than 5 microns and have a length to diameter ratio greater than 3 you approach a condition aptly described by Dr. Malcom Ross of the U.S. Geological Survey at the NBS meeting just mentioned of shutting down the face of the earth Particles of this type are everywhere and would contaminate any product containing a mineral The EPA faced this problem in 1973 in writing emission standards for the spraying of containing products and decided to treat it by setting a % by weight maximum limit Their reasoning was as follows The intent of the percent limiits to ban the use of materials which contain significant quantities of asbestos but to allow the use of materials which would 1 Contain trace amounts of asbestos which occur in numerous natural substances and 2 include very small quantities of asbestos less than 1 percent added to enhance the material's effectiveness 1 1 CFR Volume 38 No. 66 - Friday April 6 1977 p 8821 -13- In order for any action by the Commission to be workable and enforceable it is absolutely essential that you provide a definition of asbestos which states exactly what mineral species and what form of these species are included and specify what particle dimensions constitute an asbestos fiber The present definition in the proposal could be applied to the rock that covers much of the surface of the earth In addition an analytical procedure and the levels of impurities that are acceptable as measured by this procedure must be specified Without the practical defini- tions the ban is virtually universal and completely unworkable To conclude this discussion I would like to summarize the Union Carbide position and expand on the approach presented in my letter of July 14 1977 which we believe is a reasonable alternative to the ban proposed by the Commission 1. The products under consideration have been in widespread use for about 35 years and we know of no evidence that any consumer has ever been harmed by them No unreasonable risk to the consumer has been demonstrated by the petitioners or by the staff Consumer exposure data have been presented which show that the exposures are both low and brief and when averaged over a year are not distinguishable from the general background The risk from such exposure if indeed any risk does exist is extremely small and is based on the extrapolation of an unproven and unproveable theory We question whether it is appropriate and whether the Act gives the Commission the authority to ban a product on the basis of a hypothetical or theoretical risk or on the basis of an absolute zero risk requirement -14- 4 We do not agree that a reasonable product safety standard cannot be promulgated to protect the public adequately from any unreasonable risk and recommend the following approach a Limit the amount of asbestos that can be used in spackling and taping compounds to two percent by weight in the dry formulation This is sufficient to gain the benefits of the use of asbestos and serves to limit the potential for exposure It differs from the % of total formulation including water suggested suggested previously in that it more closely defines the content in the final product in the form that it is sanded It is also at a level where analysis is more reasonable b Require a warning label including proper work procedures on all compounds under the jurisdiction of the commission whether packaged for direct consumer or commercial use in consumer contact This turns to good advantage the widespread public awareness of the possible potential hazards of asbestos to encourage that the product be treated according to directions and not abused It also gives the user a choice Thank you very much for this opportunity to speak to the Commission I will be glad to answer any questions you may have or to provide any additional information we have available AIRBORNE AGRESTOS FIBER CONCENTRATION CONCENTRATION PAPING SANDING Fibers cc longer than 5 micrometers L Ot ral 18 -~ oy w fe n ma ~ a = _ w J J 31 19 See Cope eead Fig Seah BIN Ty ea repay^' fl ROHL ET AL 3 EARL BUEN Up inaptiaig hain Cy MRS AE OT Si NEW YORK CITY t So wv ... --DEN| VER CO | vp cree foeee ede Poo Te bef ee pL MINNEAPOLIS MN Asbestos free 1 | UNION UNION UNION UNION HIALEAH FL ' . ee ens " FT LAUDERDALE FL : FT| a 1 . DETROIT at. ! ~ = poonoae MMII | a a Senne | Senne e e e eden ewle ow bee nes nS | Ons SOS ee eee eee ee ee ee CARBIDE CARBIDE CARBIDE CARBIDE ee fe see Pl ee OOO | OO OE CARBIDE CORPORATION wee CORPORATION CORPORATION ed | TX DALLAS | CORPORATION | | i & : : ln . Laucceoae,FL ee ens Snes oo - ere even Te | | - : : | 1 4 | | S| 4. FALLS | | | : rn NIAGARA FALLSNY a ! Poo de cee eee lee eet. ete | | | ) of | | i } 1 | . ro | ENVIRONMENTENVIARONMENLTAL | DENVER CO Asbestos Freel ' | H 7 375711703 | 375711703 ' var ta, co (a besitos Tovey Anty) i | a | i 1 ot LONATIONS LONATIONS 375711703 | HEALTH HEALTH | OSHA OSHA { INSPECTIONS OSHA i INSPECTIONS OSHA INSPECTIONS COMPLIANCE COMPLIANCE . INSPECTIONS COMPLIANCE COMPLIANCE ee COMPLIANCE I COMPLIANCE : 1 COMPLIANCE COMPLIANCE | tit tt 1 | i 1 { 1 =< _. TYPE TYPE HAND SAMPLES HAND SAMPLES GO TAKEN POLE TAKEN SPACKLING SPACKLING ' 3 PANELS CRYWALL CRYWAL 19 PANELS DRYWALL INCL CELLINS CORPORATION 7 CORPORATION UNION UNION CORPORATION CORPORATION CARSICE CARSICE CARSICE CARSICE CARSICE CARSICE - to q i i , \~ +- SANDING IN ATPOTONE SANDING OREPATOR OF OREPATOR BREATHING ASERSTOR CONCENTRATIONS TARE BREATHING CONETRAIONS JOINT ZONE COMPUND CONETRAIONS PMETNS COLT DE OPY MATERIALS AND CLEANUP AFTER SANDING WET OFMATERIALS byt pa MATERIALS DRY MATERIALS MATERIALS SWEEPING AND CLEANUP CLEANUP SWEEPING SWEEPING uv AFTER SANDING ee ed ~ $ perocan te allt Pya-le - ~ sweeping sweping after Minutes | Minutes Minutes ae - 15 _ = ab t - sweeping swepingsweping 30 Peep eee pee] after after ee eee fp fe Minutes Minutes Minutes Minutes Minutes Minutes Minutes eel 25 25 ep ee ey ye bp ee ee OSHA COME LANGE 20 15 penne Le... - ere te Pee os - INSPECTIONS INSPECTIONS INSPECTIONS INSPECTIONS INSPECTIONS INSPECTIONS INSPECTIONS INSPECTIONS INSPECTIONS INSPECTIONS LIANCE LIANCE LIANCE LIANCE LIANCE LIANCE w : rary an - a t rey ae 10 ees ee a eee aie ef ere eed ee - } INSPECTIONS INSPECTIONS - 2 bo wd. es ns es _ we -}- |]- - | - =H - a . its its its e -] ee 5 ' eee - - se, - Pn Soeennnes Senna ~ eee ---} = -~ fa. e oe ( re 5817132 5817132 are 5817132 -_ -- - Fe 4 nt 4 sg be 497 497 497 497 497 oy - i tc ty w ls .} * =f- DNIT DNIT DNIT 5817132 5817132 5817132 5817132 17240 5757 1724005757 1724005757 1724005757 1724005757 1724005757 1724005757 1724005757 17240 5757 1724005757 1724005757 1724005757 1724005757 1724005757 1724005757 1724005757 1724005757 a DNIT : ara ot a we 61 61 on --- - N 5 1 2 1 3 - 1 BBER OF SAMPLES FIGURE 2 ASGISTUS ASGISTUS EDUCATION EDUCATION 0006131 Union Carbide in California tions but we has mined asbestos ore and operated an ore since 1963. We market asbestos fibers for do not make any products from asbestos benefication plant industrial applica- . We have provided medical surveillance for our asbestos plant employees and conducted monitored air monitoring since 1963. as often as once per month Some of our plant to ensure that our areas are currently dust control measures are effective Safety meetings posters and individual consultations are some of the means used to advise employees of the asbestos health hazard The use of safety equipment is rigidly enforced and employees are constantly reminded of safe procedures and precautions to take to preserve their health Smoking has always been prohibited in certain plant areas and has been generally discouraged by communicating to employees the apparent connection between an increase in lung cancer and asbestos workers who smoke Since January , 1977 smoking has been prohibited on all plant property Medical surveillance has included chest ray and pulmonary function analysis and we have recently added sputum cytology to our medical program Before initiating new rules or programs we thoroughly discuss them with employees This facilitates the implementation of changes and demonstrates to our employees why we are making the changes They can then understand our reasons and cooperate with us in establishing a safe working environment Our customer education includes mailings and personal contact through meetings seminars and sales calls Our salesmen are thoroughly familiar with the asbestos health hazard and are aware of regulatory requirements safe handling methods etc. Our bags of asbestos have carried a warning label since 1968 four years before the Federal OSHA standards were protul gated to require this air monitoring medical surveillance and other safety Bicasures We have provided free air monitoring for our customers for several yours This often often provides us with the opportunity to discuss the asbestos hazard and safety precautions with our customer's employees We have prepared booklets containing inform related to specific applications These booklets contain general information on the asbestos health hazard regulatory requirements typical air monitoring results and other persianent item He have also parpated information for presentation to technical society 1 betings or any group who is interested in the asbestos Lory We have in our files a large number of items which we send to customers and including all of them with this document would pake it very voluminous The attached list of them is essentially complete and the items are available for immediate mailing if so desired The State of California recently enacted an Occupational Carcinogens Control Act and asbestos is one of the 16 substances affected by it The OSHA Asbestos Standards have been modified to include the provisions of the Act which also provides for a massive education program We have worked closely with State personnel to develop standards which are offer and also practical and enfor^oble We have participated heavily in the education program Preventing Cancer by serving on panels and assisting in workshops held at four different California cities in done and July Asbestos can be used safely in essentially all key to safe working and public environments is potential health hazards and how to handle and excessive airborne contamination of its many applications The a thorough knowledge of its use it without creating Prepared by John .. Byers Marketing Manager Union Carbide Corporation Metals Division Hiagara Falls NY - August 29 1977 INFORMATION AVAILABLE FROM UNION CARBIDE CORPORATION ONTHEHEALTHHAZARDS OFASBESTOSAND HOWTOUSEITSAFELY Material Safety Data Sheet & Typical Chemical & Spectrographic Analysis of Calidria Asbestos Testimony by George W. Wright M.D. before U.S. Dept. of Labor Occupational Safety & Health Hearing on Proposed Occupational Asbestos Standard March 14-17 1972 Testimony by J. Corbett McDonald M.D. - same as above OSHA Regulations EPA Regulations Airborne Asbestos National Research Council 1971 Airborne Asbestos - Summary Airborne Asbestos - References Asbestos Bulletin Asbestos Information Committee London - 9/72 CIBA CETGY - UK 2/72 QAMA Folder WHO Report - 10/72 Dust Counting - S. G. Bayer R. D. Zunmalde T. A. Brown - Feb. 1969 NIOSH Dust Monitoring Equipment & Costs - 2/19/73 Instructions for Sempling of Airborne Asbestos Fibers Procedure for Pump Calibration used for Monitoring of Asbestos Dust Emissions AIA - Protecting the Asbestos Worker - Asbestos and Health AIA +4 - The Asbestos Information Association America Asbestos and Health Questions and Answers What Asbestos Is How and Where it Is Used What Every Employer Should Know About Asbestos - 2/71 Asbestos In the Atmosphere Atmosphere Asbestos in Water AIA - Molding & Fabrication of Containing Plastic Products Work Practices Partnership for Prevention - The Insulation Industry Hygiene Research Program Asbestos - Reprint from National Safety News - 10/73 Asbestos Health Question Perplexes Experts C & EN - 12/10/73 Disputes on the Safety of Asbestos - New Scientist 3/7/74 JLM - Chrysotile Asbestos in Plastics Asbestos & Silica Dust in the Drywall Industry Part 1-Nov./Dec 1975 Asbestos& Silica Dust in the Drywall Industry Part 2-Jan./Feb 1976 Detection of Chrysotile Asbestos in Airborne Dust from Thermosetting kesin Grinding - 1975 Calidria Asbestos Pellets Health and OSHA Information Calidria Asbestos 244 Health and OSHA Information Calidria Asbestos 600 Health and OSHA Information Calidria Ashestos Pellets JLM ASBESTOS - 10/71 92-385 AIRBORNE ASBESTOS FIBER COUNTS during CONSUMER INSTALLATION OF DRYWALL IN A LARGE ROOM Dates Sampled Date Reported August 3-11 1977 August 29 1977 Samples Collected By B. L. Ingalls Union Carbide Corporation Samples Analyzed By B. L. Ingalls & G. J. Spencer Union Carbide Corporation Reported By H. B. Rhodes Union Carbide Corporation Union Carbide Corporation Metals Division Niagara Falls New York SUMMARY AND CONCLUSIONS Asbestos exposure during and after consumer installation of drywall for the finishing of a 12 x 24 basement recreation room was measured Nineteen panels of wallboard each 4 x 8 were required to cover three walls and the ceiling of this room About 80 pounds of ready taping compound containing 1.75 by weight asbestos as manufactured and 2.6 by weight when dry was used Personal and area samples were collected throughout the installation using 0.Su porosity Killipore filter and precalibrated MSA pumps The filters were mounted and counted by optical phase contrast microscopy in accordance with the latest March 30 1977 draft of the N10SH method CAM 239 The maximum ceiling exposure for any of the operators was 1.3 cc which occurred during cleanup after sanding Eight weighted average operator exposures ranged from 0.1 to 0.2 cc with an overall average of 0.2 cc General area weighted average basis A general house survey values were well below present installation ambient background exposure levels did not exceed 0.1 cc on an hour time- in the work area cellar or 0.02 cc in the living rooli on the day after the job was complcted showed that all 0.01 cc and had not been changed appreciably by the It is questionable whether this is different from the 1 1 fibers having > 25 length cc mcans asbestos fibers having an / and micrometers micrometers in in per cubic centimeter of air TABLE OF CONTENTS Section OBJECTIVES | TEST LOCATION AND GENERAL PROCEDURE SAMPLE COLLECTION AND FIBER COUNTING PROCEDURES PRESENTATION AND DISCUSSION OF RESULTS Completion of Studding Hanging Drywall and Start of Taping 3-8 First Sanding Cleanup and Application of Finish Coat of Compound 8/6/77 Second Final Sanding and Cleanup 8/10/77 Residual Exposure After Completion of Installation 8/11/77 Summary of Results During Drywall Installation CONCLUSIONS CONCLUSIONS Page 1 1 2 A 5 6 6 7 7 LIST OF FIGURES FIGURES No. Sample Locations - Prior to Drywall Installation Installation of Drywall Paneling Application of Tape and Joint Compound Firsthand Sanding of Tape Joint Compound Sanding of Finish Coat Cleanup After Final Sanding flo LIST OF TABLES Title Summary of Airborne Fiber Concentrations Drywall Installation Page 14-15 This study had the following objectives 1. To measure asbestos exposure during the consumer installation of 19 panels 4 x 8 of drywal~ 2. To measure residual household exposure to asbestos after completion of the drywall installation TEST LOCATION AND GENERAL PROCEDURE The tests were run at a one story wood and brick single family dwelling located in Lewiston New York The house was approximately 20 years old and accommodates 2000 ft of living area The original construction utilized plaster walls and no known subsequent consumer or professional use of materials capable of releasing substantial quantities of form asbestos fiber had occurred In this test studding was installed over three walls cast south and west and the ceiling of a 12 x 24 basement recreation room Nineteen 4 x 8 panels of 3/8 gypsum board were then fitted and nailed into place The joints were finished by the following procedure 1. Compound was hand trowelled over all of the joints and the tape was embedded and covered The nail holes were filled in at the same time 2. When the initial taping had dried a second coat of compound was added and sanded when completely dry 3. Following the sanding a finish coat of compound compound was applied 4. When completely dry the finish coat was sanded About 1-1 cans 62.5 lbs each of compound rud were used in this installation The mud was a ready obtained from Florida Relling Hills Inc. of Ft Lauderdale Florida It contained 1.75 asbestos by weight as received and dried to 2.6 by weight The drywall finishing was done by a couple whose previous experience with drywall had been limited to the patching of a single seam in a prior residence They received hours at the start of the intermittent instruction over a period of taping from another consumer with limited about 1-1 experience and completed the job on their own The work was done in a wanner that was considered to be reasonably representative of middle roard oad consumer use All joints were sanded to give a good smooth finish No specific precautions were taken to avoid dust during sanding and cleanup but deliberate efforts to create airborne dist were also not made personal airborne The installation divided naturally into five steps and both area and air samples were collected to monitor any significant generation of asbestos fiber as follows 1. The completion of the studding the hanging of drywall panels and start of taping 2. Completion of the taping and application of the second coat of compound No samples taken 3. First sanding cleanup and application of the finish coat of compound 4. Second sanding and cleanup 5. Residual exposure after completion of installation SAMPLE COLLECTION AND FIBER COUNTING PROCEDURES P and test pumps The latest draft of the NIOSH sample collection and counting CA 230 dated March 30 1977 was used as thegeneral basis 0.8... Samples were collected on Hillipore filters of 0.8... porosity procedure for this using H.S.A. precalibrated at 2 liters per minute The counting procedure specified in this draft differs significantly from earlier editions in that 1. Substantial changes have been made in the selection rule covering which fibers encountered by the reticle are to be included in the count This largely eliminates systematic bias due to fiber size distribution 2. The total coefficient of variation is expressed as a function of the total number of fibers counted instead of a single value applicable to all situations A minimum total count of ten fibers is also required These are clearly substantial improvements but the method still has some serious shortcomings particularly when applied to situations where airborne fiber concentrations are low and where asbestos particulate materialmaterial is present ) refinquents Both of these situations exist in the present study and certain in the procedure have been necessary in order to present the results in the most understandable and meaningful fashion It should be emphasized that these are additions to the precedin and are not in conflict with it The legal basis for refinements to be described is found in the following quotation from P & CAM 239 3 Interferences an atmosphere known to asbestos all particulates with contain a to diameter ratio of3 to 1 or greater and a length greater length information thon Su should in the absenceoof f other as asbestos fibers and countedas such information be considered imphasis added Sataples See Safety example Obtained A Peport rom and on the Fiber Content sing the Procedures of fighty Industrial of the Occupational Ocupational Talc and Health Administration HBS May 1977. This report is one of the principle reasons for an international confernece on the problem Sponsored by NBS and scheduled for July 18-20 1977 -3- The approach here emphasizes the development and use of other infor- mation to obtain the most intelligent assessment of what is seen through the microscope In this connection it is important to realize that optical fiber counting is not an exact science but an art It requires a unique blend of tal- ent training and concentration An experienced counter develops both an eye and a counting rhythm which permit him to recognize fibers decide which fibers are of the appropriate type and dimensions to be counted and to move rapidly from field so the counts do not take an inordinate amount of time rules The objective is to provide to judge between the various the experienced operator with a sel of ground types of fiber and put them in certain classes Under contrast illumination chrysotile asbestos has some very distinctive characteristics It is typically dark appearing composed of randonsized bundles and flexible like threads with curvature When chrysotile fibers are short however i.e. 5-10 they often appear as perfectly straight dark like particles Fibers of amphibole asbestos are usually larger in diameter than chrysotile and more rigid and like in appearance They can however break down into very fine needle material With the exception of crocidolite the amphiboles also can contain prismatic crystals which usually have the appearance of chips The amphiboles normally refract light differently than chrysotile under phase contrast and appear brighter As particle size decreases however light refraction and contrast are diminished and the particle will appear darker and less definitive At this size it cannot be distinguished distinguished from chrysotile fibers of similar dimensions In addition to the three kinds of fiber just described i.c. chrysotile amphibole fibers and chips and material that looks like the capii-- boles particles are frequently encountered that meet the NIOSH fiber definition of / 3 5 but are obviously not asbestos in eny form These include such things as fiberglass poles some clay and mica particles organic fibers and linear agglomerates of nonfibrous material On the basis of the optical characteristics discussed tempered with broad operater experience with a wide variety of known particulate materials fiber counts at this laboratory are made and reported in the categories de- scribed below Materiel which is obviouslnoyt asbestos is not counted even though it meets the D 53 L ... criteria 1. Chrysotile asbestos be Any fiber having an / > end a length 25 that is in the operator's judqcnt chrysatile in the event of doubt any fiber having having the proper diensi ano d n das rk appearance will be included included as chrysotile On this basis the short dark amphibole fibers where present would be reported as chrysotile 2. Possible amphibole ~ Any fiber of the appropriate dimensions dimensions is thant ot judged to be chrysotile and is not obviously material other than asbestos This would include all amphi boles and materials similar in appearance In particles as all possible this approach all doubts are resolved in favor chrysotile or amphibole so it is biased to give asbestos particles without masking results by of including including a high count including for =~ particulate that is neither asbestos nor fibrous It is backed by counter experience gained in approximately 250 site sample collections and the counting of over 1500 filters A photo library and a reference sample collection of a wide variety of known materials which contain amphibole or amphibole materials are maintained It falls within the other information allowed in the NIOSH procedure The other counting problem encountered relates to the very low airborne asbestos concentrations found in most of the samples The NIOSH procedure sets an optimum fiber density on the filter of 50 to 100 fibers per 100 viewing fields and states a minimum density of 10 fibers fields Within these limits the method is claimed to be applicable to a concentration range of 0.1 to 60 fibers with a total coefficient of variation of 0.24 - 0.36 The validity of these claims particularly with regard to accuracy is a subject of considerable controversy at this time The discussion of this question is well beyond the scope of this study For the present work sample times were adjusted within the limits set by the nature of the operation to deposit the proper density of fiber on the filter Where this was not possible additional fields were counted in increments of 100 fields until the minimum of 10 fibers was achieved or a minimum of 500 fields were counted Separate results for chrysotile and possible amphibole are reported at values rounded to the necrest significent figure Fibers fields and the total number of fields counted are also shown in all cases to provide more complete information PRESENTATIPREOSENTNATION ANDDISCUGSTON OF RESULTS tested section A detailed listing collection time and these airborne fiber of all samples taken including location operation counting results is provided in Table 1. In this counts will be related to the corresponding drywall installation step The ceiling and eight weighted average exposures for the consumers involved are described Comploe f t Sti uro kin ng Hanging Drywall and Start of Teping 8/3/77 8/4/77 8/5/77 8/5/77 Figures b and 2 show various stages in the hanging of the 19 sheets of gypsum board Seven of the 19 sheets used in the ceiling and four of the shrets used in the walls required cutting and triewing in varying amounts through to achieve proper fit the application of the Figires tape and a B the second and c coat of continue compound the job over both the tape and the nail heads Arca air samples were collected on 8/3/77 in the living room see Figure ( and the cellar see Figures b and c prior to the use of the mud Personal sarg.les were then collected on both operators during the start of the taping An area and a personal sample were collected in the cellar on the following day 8/4/77 while a single operator completed the first installation of compound No samples were taken on 8/5/77 when the second coat of compound was applied The fiber count results are summarized in Table I and include samples 73 52 3 2 53 and 70 The upstairs arca sample showed a concentration of 0.004 cc prior to the use of the compound The highest value found in the working area was 0.3 ec for Operator 21 during taping ; - Both operators were in weighted average ( exposures accordance with NIOSH procedures the arca about 11-1 hours on 8/3/77 but time- have been based on 8 hours 480 minutes in as follows Operator Operator 480 Operator 2 0.12 TTHAHA = 607 0.08 + 84 0.108 0.12 0.12 cc 480 The completion of the initial taping on 8/4/77 took Operator 2 2 little over four hours At that point he left the house Both the personal and area samples during this step were 0.02 cc so that his actual TUA exposure would be 0.02 252 TUA TUA = 0.02 252 480 f = 0.01 cc If he had elected to remain the rest of the day in the work area in the cellar his TWA would not have exceeded 0.02 cc No sarples were on 8/5/77 The completed are covered with compound taken while the second coat of compound job is shown in Figure d Note that for a width of a foot or more was the applied joints First Sanding Cleamur and Applicatioonf Finish Cosotf Compound 8/6/77 8/6/77 After the second coat of compound was dry the joints and the covercd nail heads were hand sanded smooth using 150 grit paper wounted on a sanding block This operation is shown in Figure a b and c After complation of sanding the dust on the floor was swept into piles with a becom and transferred transferred with a dust pan to a bag and deposited with the trash The sweeping is shown in Figure d A finish coot of compound was then applied to all joints and nai , heads Personal samples were collected in the breathing zone of both operators during the sending and subsequent cleanup Separate area samples were also obtained during sanding and during cleanup Area samples were obtained in Loth rooss cellar and first floor living room for the remainder of the day during the installation of the finishing coat of compound Relevant samples here are 1-76 89 14 94 18 75 71 30 31 and 10 Table ) Personal exposures during sanding ranged from 0.5 to 0.9 cc and were 0.7 and 1.3 cc for operators operators and 3 respectively during cleamp The cellar area samples showed 0.2 cc during sanding 0.7 cc during cleanup and dropped to an average of 0.03 cc over the remainder of the day The living room sample was 0.013 ce during the application of the compound basis his Operator 2 was present in ectual ectual hour THA exposure the house would be for about 5-1 hours On this THA = 0.9 + 28 0.52 480 +480 17 237 0.033 = 0.162 0.162 cc -6- If it is assumed he remained in the cellar at an exposure of 0.033 cc for the remainder of the day the TWA would be 0.172 while the remainder of the day in the living room at 0.013 cc would yield 0.166 cc It is realistic to round all these values to 0.2 cc In this same sequence Operator 3 had 415 minutes accounted for and was largely in the upstairs arca or out of the house for the 65 minutes needed to completo 8 hours Using the 0.013 cc level found for the living room a TWA of 0.19 cc results round to 0.2 cc Second Final Sanding and Cleanup 8/10/77 After the finish coat of compound was completely dry it was sanded in thesame nonner as just described This operation is shown in Figure 5 and the corresponding cleanup is shown in Figure 6. The large amount of dust generated clearly previous is evident This cleanup differs from the previous one in that after the dust had been swept into piles it was taken up a shop vacuum cleaner instead of a dust pan The 17 samples relevant to this operation are too numerous to list individually but appear in Table I SECOND SANDING Personal samples during sanding ranged from 0.2 value cc was found during cleanup This latter AND CLEAFUP 8/10/77] to 0.9 cc and a level of 1.2 is not significantly different from the 1.3 cc found in the previous cleanup The area samples in the cellar ranged from 0.1 to 0.5 cc during sanding and cleanup and dropped to an average of 0.04 cc for the remainder of the day The living room showed a level of 0.02 cc throughout the entire day Operator 2 was present for about two hours during this operation On this basis his actual hour TWA exposure would be 0.16 cc If it is assumed he rowsined in the cellar or in the living room for the rereinder of the day his THA's would be 0.19 and 0.17 cc respectively These all round off to 0.2 cc Operator 3 had 382 minutes was in A TWA general thegeneral area of 0.17 round to of the living 0.2 results of personal sampling accounted for and room for the remainder of the 8 hours Residual Exposure After Completion of Installation 8/11/77 first On the day following the completion of the drywall installation the floor rooms adjacent to the cellar entrance were cleaned with a household vacuum cleaner A personal sample was obtained on the operator during the cleaning and area samples were taken for the remainder of the day the living room kitchen stanwell to the cellar and in the completed recreation room The results are listed in Table as samples 72 76 2-4 70 and 56 Within The results ranged from 0.001 to the limitations of the method this 0.006 cc and averaged 0.003 cc is not different from the value of 0.004 cc for sample 73 It is also in the range of the general background exposure and the household is not being subjected to continued high exposure exposure to asbestos as a result of this consummer drywall istallation % Summary of Results During Drywall Installation The ceiling and eight TWA values so far described for the operators during the various steps in the installation are summarized below The corresponding TWA values for the cellar and the living room are also shown Personal Operator # Oporotur 7 Operator * 8/3/77 8/3/77 Completion of Studding Hanging Drywall Drywal Start ) Ceiling THA 0.3 0.1 - 0.7 0.1 - 8/4/77 Completion of Tape Installation Ceiling THA : 0.02 - - 0.01-0.02 - 6/5/77 8/6/77 8/6/77 8/10/77 es Second Coal of Compound ~ Compound No Samples Samples SamplesSamples Taken Taken First Sanding Cleanup Finish Cont Sanding of Finish Coat ofCorpound _C _ leanup Ceiling THA Ceiling TWA - 13 0.7 - 03 0.2 . 03 1.2 - 02 0.2 8/11/77 House Cleanup After Installation CellingCelling THA 0.004 0.001 Collar Work Area - Living Loun - 0.08 - 0.02 0.004 - . . 0.1 - 0.01 . 0.1 - 0.02 - 0.004 . 0.000 1 All results expressed as fibers 25 The highest ceiling exposure for any of the operators was 1.3 cc which occurred during cleanup For the three days when containing dust generating operations were in progress the TWA's for the operators involved ranged from 0.1 to 0.2 cc and averaged 0.2 cc The sanding and cleanup operations with two people working took 2-3 hours The area A's in the cellar where the work was being done ranged from 0.08 to 0.1 cc during operations but was measured at 0.004 cc for the after day value the after ofonly installation was 0.0 / during completed The living room showed the the bighost sending but recorded only 0.004 cc before and 0.006 [ cc after contamination of the project It is clear that there was no significant the rest of the house during the operation nor any residual contamination after it was completed CONCLUSICHS CONCLUSICHS The data as obtained and reported herein support the following conclusions: 1. Consumer installation of room diywall panelling with tape- approximately joint compound weight gives containing containing approximately approximately 2.57 asbestos dry asbestos exposures substantially substantially substantially less than both the present eight OSHA standard of if cc ceilinangd 2 cc for an time weighted average and the proposed standard standard of working 55 / ceiling and 0.5 fibers TWA These stendaris are designed to protect the worker for daily exposure for an entire lifetime 2. Household exposures after the installation were substantially below 0.01 cc and had not been chonged appreciably by the present activities It is questionable wirther this is different from natural natural backgi ound - SAMPLE LULATIONS LULATIONS PRIUK PRIUK TU WALLWALL INSTALLAT INSTALLAT INSTALLAT LUIN US a 1 a First Floor Living Room - Monitor Located over Fireplace mantle 1 b Cellar with studding East walls Recreation in place Room with South and 1 c Cellar Recreation Room studding in place North and walls with East FIGURE 1 OF INSTALLATION DRYWALL PANELING West walolf cellar 2 c West wall and ceiling 2 d East wall and ceiling FIGURE 2 APPLICATION OF TAPE & JOINT COMPOUND 3 a Covering nail nail nail tape joint joint compound holes with 3 b Applying tape & joint compound between drywall seams 3 (compound Aplying to ceilng ceilngceilng ceilng drywal jointdrywal joint joint ) Applying Aplying ApplyingApplying Aplying Applying tape joint compound compound compound compound to ceiling ceiling ceilng drywaldrywalldrywall cation After tape joint jointtaping compound compound second secondsecond 3 ( cation cation cation ) cation cation After After After tapingtaping taping of tape tapte ape joint and and second joint compoundcompound compound second appli- appli- appli- apli- apli- appli- FIGURE 3 FIRST SANDING OF JOINT COMPOUND 4 b Sanding ceiling joints gy y aw envy are.) 4 c Dust accumulation after initial sanding 4 d Sweeping after first sanding FIGURE 4 FINISH SANDING OF SANDING UF COAT + an Mahe.Bray ade cS oS Bi SRS DS a 7Pes Ne vt 5 a Sanding ceiling joints 5 (b) Sanding wall and ceiling joints 5 ( c ) Sanding wall joints FIGURE 5 CLEANUP AFTER FINAL SANDINGS "tw 6 a) Dustfinal final sanding sanding sandingacumlatsioannding Dust acumulation ac umulation final sanding accumulatiaoccnumulation acumulation aftearfter after after Cr ae doar tae . temy me age ae e fl y . e my vel e ama: - 6 (b) after Sweping sandingsandingsanding Sweeping Sweping Sweeping Sweping after after after after sanding sanding sanding final final final final 6 (c) sweping sweping with after after intial Vacuming Vacuming Vacuming Vacuming Vacuming Vacuming Vacuming sweeping sweeping sweeping sweeping sweping with after after intial initial broom broom broom broom initial intial initial FIGURE 6 ne 4327 4327 Sumple 7 NO _ Bite 73 8/3/77 a reas wee at Description Beratun No. of Filter SectioSnecstions Used 600 Aa fp poand Located 500 5 tla @ 5! above saitel of f 8/3 52 20A 227 fi - " Kubra bangtans of asbestos IGO 1 ahove t- t- Last construction construction w th center of run 100 1 8-3 B 432 201.6 27 Ven anal Upcrator #i Taping joints with re my mia J / 7 P 177 Va Personil Operator 2 Tapine joints 100 1 with really real y mix BAAL 53 8/4 9.30X 252 Personal Genator 2 Taping joints 260 2 with realy realy 0.1x 70 8/4 9-35A 1.137 253 Area - Barise tapane Located = G 200 1 above our area near conter of north cellar will ] 0.00-1 0 o 63.5 0.09 0 25.5 0.2 16 0.1 10.5 0.08 i 0.003 7.25 0.02 5.5 0.02 0 0 D , HO 8/8/77 100 1 16 8/6 10-6CA 10-6CA 10 56 Personal overaton 2 fland sarding 01 w5 89 2/6 CCA 11.2 11.2 24 Prions Opreator 2 Hand sanding 100 1 face paint cuntsund 8-14 8/6 11 58A 12.1GP 12 fred 0perator ) Sweep up after 100 1 first sai dang 94 8/8 10-016 46 Personal Operator # 3 Finding Finding 163 } Tape gant compatt compatt 8-18 9 10.55A 202 34 Peramal Peramal operator 23 Hand santing 100 1 Tape zonal songmund 75 816 11.57A 11.57A 11A aa Personal Operator Operator 3 100 after first sandamu 57A 23P 24 Area Ourting First sanding sanding of tipe 100 1 71 8/6 Located 6? above floor near center of north wall cerisel 57A 8-30 8/6 127 15 Area - ring after first sanding 100 1 -6 flowe wear center of north wall color 31 8/6 39P 46P 237 Aren After Sanding and sweep up During 100 1 final application application of tape juant Located near center of nurth wall cellur 23P 8-10 8/6 39P 256 Area After Sanding and sweep up During During 300 i final application of tape juint compound Located First floor upstairs Living room on mantle of fireplace 53 0.8 21.5 .. th 1.0 43 0.7 35 C.7 15 0.7 25.5 0.2 14.5 0.7 10 0.03 8.5 0.01 6.5 0.1 1 0.02 4.5 0.3 5 0.04 5 0.1 G 0 0 & iy , 1 0.003 2 0.000 cee Y 8-20 65 14-8 gare 9/10/17 8/10 8/10 T 8/10 8/13 8/10 3/10 8/10 8/10 4.529 8/10 11-85 8/10 9-55 8/10 8/10 8/10 8/10 8/10 wo Anal doematee 1971 en ae eeeEL Parganalteration Parganalteration Parganalteration 42. Sarding wille wille f Paketer Paketer 2. Sandien ething ething . Zonal oe dss stor 2. facin je Sanding hy Sundara 100 final surfing seen ve ve in north wall 8/11/71 76 8/11 8/11 70 8/11 11 Bae ta ES armor kiteren and sending cleans 500 Ditton completion of work mantle of fire- completion of work 500 Located in stairway of above cellar floor Bee Dy in base following completion completion of work ert I 2 fgega ail 0.05 29 0.0 C. 0.054 --.3 0.001 0.006 0.001 0.00 0.01 . 0.0 7 0.02 0.02