Document G5rK5gyVJrJXEq2XpDYygdd2n

FILE NAME: Trade Publications (TR) DATE: 1973 May DOC#: TR063 DOCUMENT DESCRIPTION: Article from Mechanical Engineering udiam oli engineering V O LU M E 95 N U M B E R 5 M AY 1973 THE COVER ENGINEERING FOR HEALTH A notorious lack-of communication between the medical and engineer ing communities has undoubtedly deprived mankind of vast areas of potential benefit. Although our recent space programs have done much to develop channels of cooperation between these important profes sions, It appears that It will be left largely to the engineer to show the way. The need is not so much for new developments as It Is for simply the application of existing engineering technology and methods to medicine and public health. It's a real challenge for the engineer. Our cover this month symbolizes engineering In medicine. Read about It In an article beginning on page 18. FEATURE A RTICLES GUIDELINES TO PROFESSIONAL EMPLOYMENT FOR ENGINEERS AND S C IE N T IS T S ....................................................... 14 A guide proposed by the engineering societies for mutually satisfying relationships between professional employees and their employers. ENGINEERING AND PUBLIC H EALTH............ William J. Nicholson 18 While engineers and technology have had an Impact on some areas of medicine, there Is an "open sesam e" for more transfer to be accom plished. TECHNOLOGY AND COST OF COAL G A SIF IC A T IO N .................... ..............................................H. M. Siegel and T. Kalina 23 Economical coal gasification Is possible, but extensive development work will be required to advance any of the new processes to the commercial stage. ELECTRONIC PIG INSPECTS PIPELINES IN P L A C E ..................... ....................................................... Harold W. Bredln 29 There's a nondestructive quality-assurance Inspection technique for determining the condition of In-service gas, oil, or crude-product pipe lines. WATER REUSE IN INDUSTRY Part 2-- Transport W ater..............E. H. Pavla and A. D. Tyagi 32 An example of the reuse and recycling of waste water that both protects the environment and recovers usable raw material. DEPARTMENTS EDITOR'S P A G E ............ BRIEFING THE RECORD .. PHOTO B R IE F S ............. INTERNATIONAL FOCUS . . ASME TECHNICAL DIGEST LETTERS AND COMMENT . CURRENT BOOKS ......... ASM E BOILER C O D E ...... ME NEWS R O U N D U P ...... NEWS BRIEFS ............. EDUCATION NEWS ....... EDUCATION CALENDAR . . MEETINGS CALENDAR . . . . .13 . .35 . .42 . .44 . .48 . .58 .59 ..61 . .65 . .68 . .70 . .72 . .73 THE ASM E N E W S ....... '....................74 W OMAN'S A U X IL IA R Y .......................81 EXECUTIVE COMMITTEE A C T IO N S ......83 CALL FOR P A P E R S ........................... 3 PEOPLE IN THE N E W S .......................84 ELECTIONS TO FELLOW G R A D E ...........85 D E C E A S E D ..........................................86 WASHINGTON W IN D O W ....................88 KEEP IN F O R M E D ............................ 92 EMPLOYMENT OPPORTUNITIES ........105 CONSU LTAN TS.............................. 112 ADVERTISING INDEX ..................... 113 CHANGE OF A D D R E S S ....................114 NEXT MONTH Long-Range Approaches for Resolving the Energy Crisis Transporting G as by Airship Noise Control: A Com m on-Sense Approach EDITORIAL STAFF J, J. JAKLITSCH , JR., Editor HAROLD BREDIN, Associate Editor SA M U E L WALTERS, Staff Editor ELIZ. CALVELL1, Assistant Editor JAN ET KOTEL, News Editor G ALINA SAZONOV, Art Editor GEO. SAM ERJAN, Art Dlrector JIM MOBLEY, Editorial Production POLICY BOARD, COMMUNICATIONS Chairman and Vice-President JAMES 0. STEPHENS Members-at-large P. G. HODGE, JR-, W. G. CORNELL, S. P. KEZIOS, D. F. WILCOCK Policy Board Representatives J. W. HOLL, Basic Engineering S. P. ROGACKI, General Engineering G. P. ESC H EN BR EN N ER , Industry G. P. COOPER, Power G. C. W IED ERSU M , JR., Research W. H. BYRNE, Codes and Stds. G. P. ESCH ENBRENNER, Nom. Com. Rep. C. 0 . SANDERSO N , Mng. Dir., Com. OFFICERS OF THE ASME RICH ARD G. FOLSOM, President ROGERS B. FINCH, Exec. Dlr. & Sec'y HENRY N. MULLER, JR., Treasurer Vice-Presidents, R. A. Bennett, C. T. Carley, Jr., D. H. Cornell, N. R. Johanson, C. H. Long, J. W. McKlarnan, A. R. Machell, Jr., G. F. Maruska, R. W. Mills, R. M. Nee, D. E. Ott, J. D. Paulus, R. Plunkett, J. D. Quinn, W. T. Reid, R. E. Roberts, W. A. Shearer, Jr., J. 0. Stephens, J. A. Talbott, F. A. Thomas, Jr., D. Zwelp EDITED AND PUBLISHED monthly at the offices of Tha American Society of Mechanical Engineers, United Engineering Canter, 345 East 47th Street, New York, N. Y. 10017. Coble address, "Mecheneer," New York. Second-class postsge paid at Naw York, N. Y., and at additional mailing offices. PRICES: to members, annually 55.00 for Initial membership subscription, 58,00 for additional subscriptions, single copy 80 cents:to nonmemhers annually S `0.00, single copy 51.00, Add 52.00 for postage to countries outside the U, S,and Canada STATEMENT (rsm By-Laws The Society shall not be responsible for statements or opinions advanced In papers o r . . . printed In Its publications (B7, Per. 3). COPYRIGHT 1973 by The American Society of Mechanical Engineers. Reprints from this publication may be mede on condition that full credit be given M ECHANICAL ENGINEERING and the author and date of publication be stated. INDEXED by the Engineering Index, Inc., and MOVING? Please U se Form on Last Page 74,000 copies of this issue printed AN OPPORTUNITIES IN ENGINEERING FEATURE ' ENGINEE a a 0o AH DDIPdJMLIKl Existing and potential developments in engineering skills and technology can be put to good use in various areas of public health. Although significant contribu tions have been made by engineers to clinical and diagnostic medicine, many other areas could benefit from the appli cation of existing technology and from engineering approaches. W IL L IA M J. N IC H O L S O N 1 Mount Sinai School of Medicine of the City University of New York The adaptation of engineering techniques and the transfer of engineering technology to the solution of medical problems is an especially appealing concept. When one considers the impact on medicine of engi neering expertise and technology that has already taken place, such devices as heart-lung machines, kidney dialysis units, or improved diagnostic instru ments immediately come to mind. The space pro gram, especially, has contributed to physiologicalmonitoring instrumentation and signal processing, as well as to a fuller understanding of certain body pro cesses. An entire subprofession, bioengineering, with over 3500 members, now functions as part of both the engineering and medical communities. The channels of communication that have devel oped between the engineering and medical com munities have followed naturally from activities of this type. A wide variety of conferences and sym posia are held annually with such topics as instru mentation, artificial organs, and patient-monitoring systems dominating the discussion sessions. Several journals specializing in bioengineering, with an em phasis on similar topics, now exist. Many universi ties have standing committees of engineering and medical faculty to cpnsider these areas of mutual co operation and interest. These developments are important, and the contri- 1 Assistant Professor, Department of Community Medicine. Based on a paper contributed by the ASME Aerospace Division. bution. of engineering to these area of medicine will continue to expand. So far, however, their overall impact on health has been limited. This can be demonstrated, in part, by a survey recently taken at Mount Sinai Hospital in New York City. The courses of treatment of all 1038 patients in wards and semiprivate and private rooms during one day were reviewed to determine the use of electronic di agnostic or monitoring equipment (excluding x-ray machines, electrocardiographs, or routine laboratory equipment for the analysis of blood specimens, tissue biopsies, etc.). The results appear in Table 1 [l]-2 During the 24-hr period of Jan. 15, 1970, only 3.8 percent of the patients required treatment utilizing various electronic gear, and only 14.3 percent re ceived such treatment at any time during their hos pitalization. If one also excludes electroencephalo graphs, used extensively in the neuro-psychiatric de partment, and hardly a new device, these percentages drop to 2 and 6 percent, respectively. Addi tionally, Table 1, which also lists the electronic ' equipment used, shows only three devices that were developed in the last decade. This limited use was not from unawareness on the part of the clinical staff nor from unavailability in the hospital. Fortune magazine of January, 1970, the very month of this survey, stated that Mount Sinai Hospital was "one of the most extensively au tomated big hospitals in the nation." What this limited use does show is that much of biomedical en gineering is irrelevant to the everyday problems of patient care. Additional evidence of the lack of impact of tech nology on the nation's health can be obtained from an analysis of the life expectancy of the U. S. popu lation over a period of time. An infant born today has a life expectancy 20 years longer than a child born in 1900. Antibiotics and vaccines, which have virtually wiped out childhood and infectious diseas es, have been the major factors in this increased life expectancy. However, the attempts of medicine and technology to prolong life in adulthood have been, to date, singularly unsuccessful. Figure 1 shows that the life expectancy of U. S. white males, at age 60, has not improved in the last 200 years [2]. For engineering and technology to achieve 'a maxi- 2Numbers in brackets designate References at end of article. 18 / MAY 1973 / M ECH AN ICAL EN G INEERING . i T C t =NNGG G m a il t o mum impact on public health, it will be necessary to look beyond the operating rooms and the research laboratories of the major medical centers to the de partments of community medicine, to regional medi cal facilities, and to the municipal departments of health. Preventive medicine, occupational health, delivery of medical care, accident prevention, and the health aspects of inner-city ghetto living all offer problems of immense scope to challenge the engi neering community, problems whose solutions can ' have a dramatic impact on public health. We have been able to send a man to the moon in an environ ment clean enough to perform major surgery, yet a I large number of America's workers labor in dust con' ditions that would be considered intolerable even by nineteenth-century standards. In other circum stances, a patient can await replacement of a mitral valve in a $150-a-day room while a few blocks away a child is doomed to a life of impairment as a result of permanent brain damage suffered from eating leaded paint falling from the ceiling into his crib. ( For a significant impact to be made in many of these broad areas of, community health, it is not nec essary that new, sophisticated technology or elabo rate gadgetry be developed. What is needed is the application of existing technology to this relatively neglected class of medical problems. Of equal im * portance is the need for an engineering systems ap , proach to such large-scale health issues. In many areas of community health, models can be devel oped, system components and their interactions de , fined quantitatively, and changes and their conse quences simulated as part of a comprehensive ap ' proach to the solution of urban health problems. Aconsideration in detail of a specific example of these broad problems--that of the health effects associated with the commercial and industrial uses of asbestos-- will illustrate the role of the engineer in their solution. ` Asbestos-associated Disease Knowledge of a deleterious health effect from oc cupational exposure to asbestos dates from 1907, when Montague Murray, a physician at London's Charing Cross Hospital, described the severe lung scarring found in a 1900 autopsy performed on a 33year-old former asbestos-textile worker who had been the sole survivor of a group of 10 individuals em- TABLE 1 Utilization of Electronic Equipment**by Patients at Mount Sinai Hospital, January, 1970, at Any Time during Their Hospitalization ***-1 ,* i ... T .fli. m i l rnitm Hu t n rtK --i r 'in w i Number Percent I Patients surveyed.............. ___ 1038 100.0 Patients using electronic device: ----- 149 14.3 on day of survey.............. ___ 40' 3.8 during admission prior to day of survey.............. ----- 128 12.3 Excluding ECG, x-ray, and service laboratories, but including EEG, isotope scanning, electromyography, audiometry, artificial Kidney, pacemakers, etc. Electronic Equipment Used on Day of Survey or duriftg A d m i s s i o n _______ Device Artificial kidney................ Frequency j of use .,. 2 Audiometer ..................... ... 2 EEG ............................... .. . 86 E M G .............................. .. . 3 Electronic transducer.......... . .. 3 Emm erson chest suction . . . . ... 2 Hypothermic mattress*........ ... 3 Monitoring system ............. . . . 30 Pacemaker* ................... . . . . 11 Pulsemeter...................... Radioisotope scanner ........ ... 1 . . . 21 Respirator (Bennet)........... ......... . . . 9 Rotating tourniquets* ......... . . . . . . . . . . 5 Ultrasonic nebulizer : .......... , . . 10 Total .......................... ... 188 Developed in the last decade. Fig, 1 Life expectancy of U, S, white males, at age 60, has not improved in the last 200 years. MECHANICAL ENGINEERING / MAY 1973 / 19 t i V. aft rr-a tr-t . .j v i b s l _JGLj!F% l .''I Fig. 2 Entrance port of a high-velocity low-volume dust-collec tion system for a band saw. The port is located directly under the cutting table, which has been moved aside in this photograph. Air velocities in excess of 10,000 ft/sec, three times typical blade velocities, are generated. &*&&& ployed in a factory since 1886 [3]. A 1930 British study [4] further documented the pervasive presence of asbestosis (the term applied to the pulmonary fi brosis and scarring resulting from the inhalation of significant quantities of asbestos) in factory workers. This led to the imposition of what were thought to be stringent control measures in British factories producing asbestos products. Later research uncov ered the existence of an additional problem. Lung cancer was suggested as being causally associated with an asbestos exposure in 1933 [5], and the associ ation was fully confirmed in 1948 [6] and 1955 [7] studies. In spite of this long history of disease, studies of Selikoff, Hammond, and Churg [8] demonstrated that an extensive health problem still exists in the U. S. asbestos industry. From observations made on the 1943 membership of the New York and New Jer. sey locals of the asbestos insulation workers union, a catastrophic health experience has been docu mented. Table 2 describes the mortality experience of this group of workers through 1971. One in five of the deaths of these workers was from lung cancer; nearly one in 10 from mesothelioma, a disease so rare in the general population that perhaps only one in 10,000 deaths are from this cause; one in 10 from cancer of the gastrointestinal tract, three times that expected; one in 10 from other cancers; and almost one in 10 from asbestosis, an occupational disease identified over 70 years ago. Nearly 40 percent of these workers' deaths can be attributed to their oc cupational exposure to asbestos. Moreover, recent studies of an asbestos-products manufacturing facili ty point to the existence of an even greater health problem in factories [9]. In addition to the extent of the disease experience, Fig. 3 The cutting of asbestos-containing pipe covering with a band saw equipped with a high-velocity dust-col lection system. Fig. 4 Three single-use respirators, especially suitable for use in construction sites, manufactured by the Welsh Manufacturing Co., the 3 M Co., and American Optical Co. 31 * - TABLE 2 Deaths among 625 N.Y.-N.J. Insulation VI/orkers Observed Prospectively 1943-1971, after Reaching 20 Years from Onset of Wo rk Total workers, 625. . . Total deaths, all causes.. Lung cancer .......... Pleural mesothelioma. Expected -- 288.5 11.2 -- Observed -- 423 84 8 Percent -- 100.0 19.8 1.9 Peritoneal mesothelioma . . . . -- 20 4.7 Cancer: stomach, colon, rectum . . . . 12.5 41 9.7 Cancer: all other sites ................ 28.2 37 Asbestosis............. -- 32 All other causes...... 236.6 201 8.8 7.6 47.5 two other important concepts were revealed in these studies: the problems introduced by the long lapse between onset of asbestos exposure and the inci dence of disease and the effects of co-factors on the intensity of disease. In virtually all cases, the occu pationally related deaths from asbestos exposure came only after 20, 30, 40, or more years since onset of exposure. This, of course, has presented consider able difficulties in attempting to apply proper con trol measures based on information of disease experi ence produced by inadequately evaluated environ mental exposures of past decades. In short, there is ' excessive time lag in the feedback loop. The other problem demonstrated by the mortality experience of these workers is that a synergistic ef fect exists between occupational asbestos exposure and cigarette smoking in the development of lung cancer. From a study of the mortality experience of individuals whose smoking habits were known, it was found that 42 of 136 deaths of 283 smoking as bestos workers were from lung cancer, whereas only one of 32 deaths of 87 nonsmokers was of lung can cer. Thus, while an asbestos exposure alone may give rise to some increased risk of lung cancer, the combination of asbestos exposure and cigarette smoking is especially deleterious to health. A ciga rette-smoking asbestos worker has approximately a 90 times increased risk of dying of lung cancer as an individual who neither smokes nor works with asbes tos. Here, as in many other medical problems, we are dealing with nonlinear systems. Unfortunately, the health problems associated with asbestos extend beyond those individuals di rectly exposed to those exposed only by virtue of working in the vicinity of the application of asbestos products, to the families of asbestos-factory workers, and to people who simply live in the neighborhood of mines or factories. Mesothelioma has been shown to occur in excess in shipyard employees such as weld ers, carpenters, electricians, and others only indirect ly exposed to asbestos [10]. Exposures at lower than occupational levels have also been linked to mesothe lioma found in family and neighborhood exposures in London [11] and Pennsylvania [12]. Here we are concerned with a problem of entirely different di mensions. The asbestos exposures that produced such disease were much lower than those of the insu lation workers previously discussed, and the risk of asbestos-related disease was concomitantly reduced. However, the number of individuals potentially ex posed is numbered in the tens of millions. Of spe cial concern in this context is the widespread dis semination in recent years of asbestos into the envi ronment through the spray fireproofing of high-rise office buildings, a process now banned in several cities. Engineering Approaches to Environmental Control Having identified the scope of the health problems associated with the use of asbestos and asbestos products, a cooperative effort was initiated at Mount Sinai School of Medicine to control human exposures to asbestos. Here the clinical and epidemiological staff was supplemented by engineers, industrial hy gienists, physicists, and even mineralogists to evalu ate all aspects of the health problem and to develop and implement various control solutions. Data were obtained on the variety of products incorporating as bestos and the potential dust exposures that might occur during their manufacture and use. Studies utilizing optical and electron microscopy and electron microprobe analysis documented the air levels and tissue burdens of asbestos from occupational and environmental exposure. Research on control strate gies was mounted to reduce asbestos exposures to all segments of the population. In the initial efforts to develop control measures to protect workers on construction sites and shipyards who cut, fit, and apply asbestos-containing thermal insulation, it was found that much existing technolo gy had never been applied in this industry. An especially easy solution for the control of dust generated by mixing asbestos cements was accom plished by requiring the manufacturer to ship these cements in plastic bags to which water can be added and mixing accomplished without generation of dust. Severe inconsistencies in the area of respiratory protection were quickly revealed. Although insula tion contractors would supply workers with half face-mask, replaceable-filter respirators approved by the Bureau of Mines, they were completely ineffec tive in protecting the workers. As no respirator maintenance program existed on any construction site, the respirators soon became contaminated in side and out and often were in a state of disrepair. Additionally, their use by individuals with impaired breathing ability was precluded by the relatively high air resistance of the filter. A three-year effort involving safety-equipment manufacturers, the Bu reau of M ines,' industrial-hygiene engineers from Mount Sinai School of Medicine, and Johns-Manville Corp. has finally culminated in the availability of three economical, approved, comfortable respirators having minimum breathing resistance. One area now under development that offers the opportunity for technological transfer specifically from space technology is that of room air-cleaning systems. As yet, no effective portable room air cleaning system is available for use in the asbestosinsulation industry. While dust control directly at the source of generation is the most desirable, occa sionally widespread dissemination occurs that re quires different control concepts. In cooperation with engineers at Florida Institute' of Technology, room cleaning systems are now being developed and tested. In this study, such procedures as air cur tains and directed air-cleaning systems are under consideration. Problems of Implementation As in all problems having significant impact on various groups in society, implementation of identi fied solutions to problems can be slow, difficult, and frustrating. Many of the solutions forthcoming from the M.S.S.M. In su latio n In d u stry R esearch Program were not immediately implemented, although they could have reduced dust exposures to one-tenth that which existed in the past. While their cost was modest in terms of the total expense for insulation work, in the absence of assurance of "across the MECHANICAL ENGINEERING / MAY 1973 / 21 board" implementation by industry, no single con tractor wished to be placed at even a slight economic disadvantage. Thus action by the federal govern ment was necessary, and an improved, but still inad equate, asbestos standard was promulgated by the Department of Labor on June 7, 1972, which incor porated some of the foregoing procedures [13]. It is important that engineering input be available for such implementation processes, especially to indi viduals proposing courses of action or budgetary com mitments by the government. Without such input, political or economic considerations will dominate the governmental decision-making process. Thus many research results and much technical develop ment may be wasted without the commitment of en gineers to the full process of development and imple mentation of the work. Occupational Health Asbestos was described in detail to illustrate the full scope of a health problem and the different as pects where the approach and the knowledge of engi neers proved of benefit. An engineering systems analysis of the commercial and industrial uses of as bestos defined the scope of the medical problem. Engineering expertise was utilized in the instru mentation developed to assess occupational and en vironmental exposures, engineering technology was identified or developed to control the excessive as bestos exposures found, and finally, engineering input into the regulatory process was of benefit in the initial steps taken by government to control the uses of asbestos. An estimated 250,000 workers ate directly exposed to asbestos. Another 4,000,000 are exposed indirect ly by virtue of their jobs. The effect on health achieved by adequately'controlling the occupational use of this substance alone could result in a saving of over 5000 lives annually. Additionally, proper con trol of the work environment can significantly reduce the exposure and risk to the general public. How ever, asbestos is only one substance found in the oc cupational workplace. Silica, talc, and other dusts are ubiquitous in the work environment; 8000 chemi cals are on the toxic-substances list of the National Institute for Occupational Safety and Health--work ers in refineries, chemical plants, and other factories are often exposed excessively to many of these sub stances. Fewer than 450 of these have established occupational standards of exposure. In many cases, the full scope of the health aspects of these sub stances has not been established, especially the long term effects and the effects of different combinations of materials. A multitude of urgent challenges await both the medical and engineering communities here. Summary While engineering and technology have had an im pact on some areas of medicine, many additional areas exist where a transfer of engineering skills and technology can have a significant impact on the so lution of major health problems. These lie in areas where the need for new developments is far less than the need for an analytical engineering approach and the application of existing technology. Many areas of health could benefit, but it will be necessary for the medical community to be educated as to what the potential contributions of engineers might be. While it is the medical community that requires the education, the initiative for this process must come from the engineering community. However, in bridging the communications gap that exists be tween parts of these two communities, engineers must reach out beyond the departments of medicine or physiology to the departments of community medi cine or occupational health. Epidemiologists and sociologists as well as surgeons and biophysicists must be contacted. Speak also to psychologists con cerned with the mental health of workers confined to the drudgery of a single task on a massive assembly line and those concerned with making the workplace, the home, or the automobile safer. However, as important as communication between engineers and the medical community is, it is only a first step. Dialogues at long range are singularly un productive. Also of limited productivity is the pro cedure of engineers coming to medicine with a gad get, a technique, or a material and asking for a use. What is productive is for engineers and health pro fessionals to work together, on a daily basis, to solve the problems confronting us. The engineer must still retain his contact with the engineering commu nity. He must stay current with new information and new technology, but for full effectiveness in the field of public health he must become totally im mersed in its activities. It might be appropriate to close by suggesting that engineers apply "Sutton's law" to their search for an involvement in public health. Willie Sutton, when asked why he robbed banks, replied "because that's where the money is." If engineers wish to make an impact on public health, they must go where the problems are. References 1 Gonda, I., and Richter, E., "Use of Electronic Equipment in a Medi cal Center, " Medical Research Engineering, Vol. 10,1971, pp. 21-24. 2 Bjorksten, J., "Approaches and Prospects for the Control of AgeDependent Deterioration," Annual, N. Y. Academy of Science, Vol. 184, 1971, pp. 95-102. 3 Report of the Departmental Committee on Compensation for Indus trial Disease, 4076, HMSO, London, England, 1907. 4 Merewether, E. R. A., "A Memorandum on Asbestosis," Tubercle, Vol. 15,1933-1934, pp. 69-81,109-118,152-159 5 Lynch, K. M., and Smith, W. A., "Pulmonary Asbestosis HI: Carci noma of the Lung in Asbesto-Silicosis," American Journal of Cancer, Vol. 24,1935, pp. 56-64. 6 Annual Report of the Chief Inspector of Factories for the Year 1946, HMSO, London, England, 1947. 7 Doll, R., "Mortality from Lung Cancer in Asbestos Workers," Brit ish Journal of Industrial Medicine, Vol. 12,1955, pp. 81-86. 8 Selikoff, I. J., Hammond, E. C., and Churg, J., "Asbestos Exposure, Smoking and Neoplasia," Journal of the American Medical Association, Vol. 204, 1968, pp. 106-112; Selikoff, I. J,, Churg, J., and Hammond, E. C., "Asbestos Exposure and Neoplasia," Journal of the American Medical A* sociation, Vol. 188,1964, pp. 22-26. 9 Nicholson, W. J., Selikoff, I. J., and Hammond, E. C. (to be pub lished). 10 Stumphius, J., "Epidemiology of Mesothelioma on Walcheren Island," British Journal of Industrial Medicine, Vol. 28, 1971, pp. 59-66; McEwen, J., et al., "Mesothelioma in Scotland," British Medical Journal, Vol. 4,1970, pp. 575-578. 11 N ew house, M . L ., a n d T ho m p so n , H ., " M esotheliom a of P leura and Peritoneum Following Exposure to Asbestos in the London Area," British Journal ofIndustrial Medicine, Vol. 22,1965, pp. 261-269. 12 Lieben, Jr., and Pistawka, H., "Mesothelioma and Asbestos Expo sure," Arch. Environ. Health, Vol. 14, Apr. 1967, pp. 559-563s 13 Federal Register, Vol. 37, June 7,1972, pp. 11318-11322. i 22 / MAY 1973 / MECHANICAL ENGINEERING