Document Gz5vxGrDOZX70G3BdOLY5MZpY
FILE NAME: National Safety Council (NSC) DATE: 1973 DOC#: NSC505 DOCUMENT DESCRIPTION: NSC Safety News - Asbestos
SAFETY NEWS A NATIONAL SAFETY COUNCIL PUBLICATION
FEflUftED 1H MONTH
After Two Years . . . Standards and O SH A ct.................... 40
ISEA Elects New Officers, Sees Problems and Promise in O SH A .......................... . 46
What You Should Know About Foot Protection__ ,............ 51
Target Health H azard s........................ . .............. r........... 53
Asbestos ...................
54
Hazard Control Through Designer Education......................... 61
Don't Sweat It-- A Look at .the Impact of. the Proposed Heat Stress Standard... .................................................... 66
What Is An Industrial H ygienist?...........................
69
On-Off Sp rin klers........... ................................................ 76
Portable Power Chain Saws (Data Sheet 320A)................... . 87
Extra-Auditory Effects of Occupational N o ise ....................... 93
Safety N ew sletter. , . Mixing Safety and Journalism ............ 100
NSC Industrial Departm ent. . . How It Serves Occupational Safety and H ealth .................................... 102
Outstanding Safety Films Named for 1973 Awards ............. 103
ONHE COYER
"Target Health Hazards" was created by Jacob Kasparian, NSC staff artist, to introduce a new series of articles to promote better understand ing of the five hazardous substances the OSHAdministration has singled out for more effective control (see page 53).
NATIONAL SAFETY NEWS Is published monthly by the National Safety Council, and It Is printed In the U .SA Copyright 1973 by the National Safety Council. No materia! from any editorial feature or department, unless otherwise stated, may be reprinted without written permission from the editor
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'P-? y ~
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This material, used extensively for protection against fire and heat hazards, ironically
i
is a recognized hazard to health when asbestos dust is inhaled excessively, caus-
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ing asbestosis, bronchogenic (lung) cancer, and mesothelioma. The industry's
many problems and its far-reaching response to O SH A cf regulations are presented.
A s b e s t o s , used since antiquity, lias widespread and important ap plications in our modern technolog ical society. Approximately 3,000 different kinds of products contain ing a s b e s t o s are in daily nse throughout the world. Its increasing use has lent urgency to the need to cope with occupational health problems related to- the .excessive inhalation of asbestos dust.
Asbestos is actually a general term used to describe several fibrous mineral silicates that occur a? white, grayish, or greenish masses, either compact or as longj Silky fibers. The most important types are:
Chrysotile-- a simple magnesi um silicate;
Amosite-- a complex magnesi um iron silicate;
Crocidolite-- a complex sodium iron silicate.
Some 97 per cent of the world as
bestos production comes from chry sotile.
Basically, the known facts, about asbestos-related disease can be summed up as follows:
1) Asbestos-related health risks today are almost exclusively con fined to the occupational setting;
2) The effects of excessive inha lation of asbestos are both time- and dose-related--this means that asbes tos-related diseases may develop, generally, only after the inhalation of substantial amounts of asbestos dust over a substantial period of time;
3 ) There is presently no evidence of risk to the general public from exposure to the minute amounts of asbestos that have been found in community air;
4) Because of the long latent pe riod of asbestos-related disease, the
disease being found today, among some long-term industry employees is not necessarily an indication of present-day conditions. It may, in stead, be a result of conditions ex isting decades ago, at a time when neither the industry, government, nor the medical profession knew much about the health effects of asbestos, or proper means for their control.
" ;VVhat Is the Hazard?
"More than 200,000 employees face risks from asbestos. The principal danger is caused by inhaling asbes tos fibers. Recent studies also have shown the presence of asbestos fibers in the lungs qf persons having no in dustrial exposure --probably due to their presence in the atmosphere near construction sites, where an asbestos mixture formerly was com monly sprayed onto steel beams as a method of making the structure fire resistant. This practice has since been banned by Occupational Safety and Health A ct regulations.
Prolonged inhalation of asbestos fibers between 5 and 50 microns long (one millionth of a meter) can produce a lung disease known as asbestosis, The'lungs cannot elimi nate asbestos fibers, so the fibers coat the tissues. If this process con tinues over a period of 10 to 20 years with significant quantities of asbestos present, the tissue reaction progresses until a generalized diffuse fibrosis occurs, causing severe respi ratory disability. There have been reports of increased incidence of lung cancer in persons with asbes tosis.
There are three primary diseases known to be caused or exacerbated by prolonged and heavy inhalation of asbestos fibers. They are asbes tosis, bronchogenic (lung), cancer, and mesothelioma.
August 1373, NATIONAL SAFETY NEWS
X' W h at A s b e s to s Is and W h e re It Is U se d
"."Tne term asbestos is derived from ,'t'egic material during World War II, majority of chrysotile used in the
'an^^cient/'i'Greek' -word meaning when.it was used as the filtering ele U.S. These fibers go into numerous ,
inepinguishpble. In reality, mineral ment in gas mask canisters. It can asbestos-cemedt products,1including
'asbestos; is- non-flammable even at be spun or woven into materials and pipe, roofing shingles, fiat and cor
/extremely U gh temperatures, it in- . fabrics used in acid-resistant pack rugated siding, millboard, cements
bibits. ceftain-iypes of chemical ie- ings and flame-resistant clothing. . and fillers, and insulated .paper.
'actions, "and is extremity flexible and
Short chrysotile fiber?. are used ex
.durable. `All these qualities combine
tensively in brake linings and auto
to. m ake'it .especially`suitable for a
Properties and Advantages
matic transmission friction materials.
rvjdde, variety..of demanding uses,
As many as 3,000 different prod
particularly,, those that .protect hu- ' ucts are in daily use throughout the
man life and property. Asbestos may -world containing some asbestos. The.
.be/unique in ' a t -its primary func- heat-resistant properties and fibrous
,-tion is .to,-save lives. -
Structure of asbestos make it ex
.'.Asbestos "is ` the generic name tremely desirable as a fire-proofing'
/givqn to a group of hydrated'silicate and insulating material. Typically,
minerals that can'be separated into asbestos is used wherever fire and
relatively,'soft,- silky fibers that have excessive heat are a threat to safety,
great, tensile 'strength. 'Certain grades
.Companies now are looking at
cgn :,he -carded, spun, and woven; fibrous glass, plastics, ceramics, and
others.'can be pressed or layered to various synthetic materials as pos
-;form .paper. Chrysotile, crocidolite sible replacements for asbestos in
(or blue fiber), and amosite;are the certain applications. However, there
' three varieties of asbestos that are generally is no one adequate sub
commercially significant today. Each. stitute material available, because
- differs fr.om the others, both physi- increased costs, poor performance,
.ally Van'd chemically.
and weight often make the substi
' ' Chrysotile is a flexible white mag- tuted material unattractive,
nesium'silicate.that can be attacked
More than 90 per cent of the as bestos fiber used annually in the U.S. is incorporated into finished prod ucts where the fiber is entrapped, or locked in, .and not free to serve as a possible contaminant in the at mosphere. Asbestos can he locked into a product with a binder, saturant, coating, or binding agent so that normal handling, application, and use will not generate significant quantities of abestos dust. Asbestoscement products are examples of "locked-in" materials, whereas many insulating materials and spray-on fire-proofing- compounds are socalled "non-locked-in" materials.
Fire-prevention and retardation, is a feature of such asbestos-containing products as: protective clothing;
-by ,'acids. It differs from other as
thermal, electrical, and acoustical-
bestos minerals in that it has a posi tive rather than a negative electrical
How Asbestos Is Used
insulating materials, roof shingles, siding, and flooring; space vehicle
charge in. water. I t now accounts for
Asbestos fibers can be classified heat shields, theatre curtains, boiler
. 9,7 ,per cent of all -asbestos used into two types: spinning and non jackets, welding screens and
/annually .in the United States. This spinning. Spuming fibers comprise blankets, gaskets for spark plugs;
high percentage of use is due in part the longer grades of chrysotile and motor casings, and insulating tapes
to .industry awareness of medical crocidolite; non-spinning fibers in for wire and cable,
studies'that show amosite and croci- clude the shorter grades of chryso
Fire-proofing plus protection
dolite to be more potentially haz- tile and crocidolite, plus the long against abrasive wear and tear (in
-.ardous to health than chrysolite as- and short grades o f ' amosite, Use cluding the caustic action of acids)
-bestos. Canada and the Soviet Union of a specific grade of fiber depends are qualities of asbestos that com
are the'leading producers of chry greatly upon application, .and to a bine to make it useful in vinyl and
solite fiber, hut small deposits are lesser extent on price and availa asphalt.floor tile, asbestos-cement
also found in the United States, bility.
pipe, asphalt paving, friction mate
Italy, South Africa,'Rhodesia, and
Longer-grade chrysotile fibers can rials, packings and gaskets, asbestos-
China,
be carded, spun, and woven to make cement building materials, paper,
Amosite, which is mined com textile products such as yarn, rov felts and many textile products.
mercially only in the Transvaal dis ings, tape, and cloth. Asbestos tex
The adhesive and binding pro
trict of South Africa, i s .a brown tiles are used to make fire-proof perties of asbestos fibers make as
ferrous magnesium silicate that oc clothing, packings, friction materials, bestos a useful ingredient in rein
curs in the same type of iron-rich gaskets; lagging cloth, and laps that forced plastics, paints, varnishes,
sedimentary rock as does crocidolite. provide electrical and thermal in roofing cements, wicks, rope, twine,
Tt is brittle and not as acid-resist- sulation.
protetcive coatings, and felts used
' ant,as crocidolite. Amosite is used
Spinning grade asbestos fibers also in paper manufacturing.
principally -in the manufacture of are used in such non-spinning appli
The spinning and weaving ca
heat insulating materials.
cations as compressed sheet packings pability of asbestos fibers is basic
; Crocidolite, characterized by a and gaskets. They also are an ingre to the asbestos textile industry. As
' deep blue color, is a ferrous sodium dient of strong asbestos paper used bestos fibers also are used in filters
1'silicate -that is acid-resistant but less in tape form to wrap electrical wires that collect dust and other air pollu
, flexible ' than chrysotile. The hulk and cable.
tants, and in Alteration systems used
of, the ymrid's supply comes from
The shorter-grade (non-spinning) in the processing of beverages,
('South/Africa. Crocidolite was a stra-r chrysotile fibers make up the great liquids, and drugs.
J u g u s t 1973,/ NATIONA1 SAFETY NEWS
55
Asbestosis
An occupational disease charac terized by lung scarring, asbestosis is one .of the lung diseases called pneumoconioses. It is the most com mon of -the three asbestos-related illnesses and is found only among those who have worked regularly and continuously with asbestos un der inadequately controlled condi tions. The average time span from first exposure to the first' clinical signs of asbestosis is 17 years, al though some cases have been re ported in as few as 10 years,
Asbestosis is believed to be nei ther malignant nor necessarily fatal. Many asbestos workers with minor
oases can and do continue to work and lead normal lives without dif ficulties.
The asbestos industry has long recognized the risk of this disease and has implemented safe-guards to protect workers' health. As far as can be determined, asbestosis never has been found in the general public, even among people living in close proximity to asbestos mines and processing plants, according to the Asbestos Information Association/ North America.
Bronchogenic (lung) cancer
A number of medical studies have linked heavy asbestos exposure with
an increased risk of lung cancer. While lung cancer occurs far less frequently among asbestos industry workers than asbestosis does, under some circumstances it occurs more frequently than in the general popu lation. As with asbestosis, the amount of fiber to which an employ ee is exposed is an important factor in lung cancer development In addi tion, it is the considered opinion of many scientists that lung cancer will not develop in an employee if he did not first have asbestosis.
Factors other than heavy asbestos exposure are believed important in the causation of lung cancer among asbestos industry workmen. The most documented example is ciga-
Some of the most asked questions pertaining to asbestos and health are answered here by the Asbestos Information Assodation/NortlT'America.
Q.-- Is the atmosphere being polluted by asbestos
sprays used .to fireproof the superstructure of buddings
under construction?
..... .
' A .-- The use o f asbestos-containing, spray-on fire proofing compounds in high-rise building construction has been banned in the United States* by the Federal Environmental Protection Agency (FEPA) because the methods developed for the control of emissions of fiber from these sources proved to he ineffective.
for asbestos exposure). Counts taken during the sweep ing and bagging of asbestos debris have reached the astronomical figure of 3,815 fibers per cc (more than ' 750 times the U.S. 'standard):' Thisresuited'"lh'--very high dust levels throughout''the shipyard :area,
.Spray application methods were never used in the U.S. shipyards during W.W. II. The alternative method used in this country, while creating dusty con ditions for the men doing the actual work, did not re sult in hazardous conditions throughout the yard, as was the case in Great Britain.
Q.-- W ill there be an "epidemic" of asbestos-related mesothelioma in the future among people who worked in United States shipyards during World War II?
A .-- It appears highly unlikely that such an "dpidemic" will occur. Predictions of this nature have been based primarily on the experience of workers in British --- not U.S, -- shipyards, where a relatively small number of mesothelioma cases have been reported among yard employees not known to have worked directly with, loose-bound asbestos products in their jobs. There are several important factors, however, which do not make the British experience comparable with that in American shipyards. These include:
The prime method of applying asbestos-containing insulations aboard British warships was by spraying, a notoriously dusty method of application. Dust counts during spraying in British shipyards have been re corded as high as 1,500 fibers per cubic centimeter of air (300 times higher than the current U.S. standard
^Editor's Note: One of the e'arliest cities to ban the, practice of spraying of asbestos mineral fiber insulation in high-rise construction was New York. The New York City Council took such action effective February 25, 1972, under Local Law 49, 1971, Air Pollution Control Code, Section 1403.2-9.11(B), enacted Aug. 25, 1971.
The type of asbestos fiber most used in British shipyards for insulation purposes was crocidolite, the variety of fiber most medical, experts agree is the most likely to cause mesothelioma. Crocidolite was not used in the U.S. shipyard work.
Q.-- D o asbestos-containing filter materials release asbestos fibers in potentially hazardous quantities into liquors, beers, wines, soft drinks, and other liquids offered for sale to the public?
A .--Asbestos-cellulose filter pads have been used in the filtration of liquids since the beginning of this cen tury, The mass production of many of our most im portant injectable drugs would be virtually impossible without the use of asbestos-containing filter media. While it is possible that very tiny amounts of electron microscope sized aibestos fibrils are released into some beverages from the use of asbestos-containing filter pads, there is no evidence whatever that the size and quantity of the fibrils released constitute any hazard to human health. This same question was raised in Great Britain a few years ago with regard to fibrils of asbestos found in beer. The furor died when it was shown that the total amount of asbestos fiber found in British beer added up to only two one-thousandths of an ounce in the total United Kingdom beer pro duction of over a thousand million gallons a year.
SB
August 1973, NATIONAL SAFETY HEWS
Asbestos Is automatically packaged at the mill and shipped in impermeable bags to prevent dust exposure, (Photost courtesy Asbestos Information Association/North America,]
In the manufacturing plant, bags of asbestos are opened and fiber handled in ways preventing exposure,
rette smoking. Studies conducted of as many as 17,500. asbestos insula tion. workers show that those" who smoke have a much greater risk of contracting lung cancer than nonsmokers in the general public -- but that those asbestos industry workmen who do not now smoke cigarettes and who have never smoked regularly, have no greater risk of lung cancer than the average man in the street who does- not smoke.
Mesothelioma
This disease is an extremely rare cancer of the lining of the chest {pleural) or the abdominal cavity (peritoneum). It is found more fre quently among those with occupa tional asbestos exposure thau among tbe general population. It also has been found among people who, in the past, lived in close proximity to uncontrolled crocidolite asbestos plants or mines, and even, on rare occasions, in the households of em ployees who worked, in crocidolite asbestos factories or mines and who presumably brought substantial quantities of this particular type of asbestos fiber into their homes on their work clothes. This has not been found to be the case with individuals exposed only to.chrysotile asbestos, which accounts for 97 per cent of the asbestos fiber used in the United States today.
Because the latent period for
mesothelioma ranges from 30 to 45 years,- it is impossible at this .late date to determine precisely the ex posure levels experienced by these "neighborhood" and "household" cases. However, they were probably quite high by today's standards. In any case, as technology was devel oped for the control of asbestos dust levels, both in the plant and out, these potentially hazardous condi tions have been greaty reduced, if not eliminated.
A relatively small number of cases have also been reported among employees in shipyards and on con struction projects who, while not working directly with asbestos, were exposed to heavy concentrations of air-bome fiber by working in close proximity to those who did, Ex posures of this type have been re duced by strictly enforced industrial safety devices and procedures.
Asbestos and the . General Public
The Asbestos Information Asso ciation/North America states:
There is no evidence ---- either from experience or from scientific research-- that any one in the general public has ever contracted any asbestosrelated disease -from exposure to minute amounts of asbestos dust being found in community
a ^ . j . <nvn u ir iA ita i n ir r r u ttn iip
air, which are many times lower , than thoseleyels that have been demonstrated to result in no excess of disease in . occupa
tionally exposed populations.
That conclusion is supported by both the Asbestos Panel of the National Academy of Sciences' Committee on Biologic Effects of Atmospheric Pollutants, and the 33member Advisory Committee on Asbestos Cancers of the Interna tional Agency for Research on Can cer, a division of the World Health Organization.
In its 1971 booklet, Asbestos, the Need for and Feasibility of Air Pollution Controls, the NAS Asbes tos Panel, which consisted of seven of the nation's experts on asbestos and health, stated:
There is no evidence that persons in the general popula tion --without occupational, household, or neighborhood exposures -- have any in creased risk of neoplasm, even though there may be ferrug inous bodies or fibers in their lungs.
According to the Asbestos In formation Association, the report of the IARC Advisory Committee rep resents the consensus of present world medical opinion on all aspects of the asbestos-health problem.
57
.' Meeting immediately after tie October 1972 Lyon Conference on Biological Effects of Asbestos, the Committee -- with representation from 10 different countries --draft ed the following opinions on asbes tos-related disease and the general public:
Asbestosis --There is at pres ent no evidence of lung damage by asbestos to the general public, The amount of asbestos in' the lungs of members of the general public is very small compared to those oc cupationally exposed.
Lung Cancer --The evidence . , . suggests that an excess lung carcinoma risk is not detectable when the occupational exposure has been low. These low occupational exposures have almost certainly been much greater than that to the public from general air pollution.
Mesothelioma -- There is no evidence of risk to the generalpublic at -'present. '
Because of some recent contro versy in the United States and Canada on this subject, the question was also examined whether there is any "evidence of an increased risk of cancer resulting from asbestos fibers present -in water, beverages, food, or in the fluids used for the administration of drugs." The an swer of the commission was: Such evidence as there is does not indi cate any risk.
Asbestos and Health Research
Extensive medical and technical research into the health effects of asbestos and the proper means for their control is being conducted at laboratories throughout the world. A significant percentage of this re search is being sponsored, co-spon sored or otherwise aided by the world asbestos industry. Two of the largest non-governmental sources of funds for asbestos-health research are the Institute of Occupational and Environmental Health (IOEH) in Montreal, sponsored by the Quebec Asbestos Mining Associa' tion, and the Asbestos Research Council, sponsored by the British asbestos manufacturing industry. Individual companies acting independently are also conducting re search into the problem.
:.5B
Controlling the Hazard
When asbestos is mined, milled, or processed in manufacturing plants, its minute, dry fibers be come air-borne like dust particles. Enclosure and local exhaust ventila tion applied to equipment or opera tions . axe the principal means of preventing employee exposure to dangerously high concentrations. Dust respirators certified by Na tional Institute of Occupational Safety and Health (NIOSH) are recommended for use by employees in some work operations.
Typical methods implemented to control dust levels include: sophisti cated dust collection systems (which combine high-power exhaust fans, duct networks, and high-efficiency filters); special methods of waste disposal; use of protective clothing and portable dust respirators; in novative wetting and dampening methods that minimize dust gener ated during production.
The asbestos-industry has devel oped a completely automatic fiber, bag-opening station that will permit workers to open the bags, remove the fiber, dispose of the bags, and ' enter the fiber into the manufactur ing process without creating dnst. In general, greater use of automa tion is being sought throughout the asbestos industry to reduce dust levels and to minimize exposure of employees to air-borne asbestos fiber.
Basically, the requirements of an effective dust control program are twofold:
1) Design fabrication processes and production equipment so as to minimize dust generation as much as possible;
2) Implement highly organized programs of industrial maintenance (including hygiene surveys) to in sure that safe levels are maintained,
Periodic monitoring of dnst con centrations should reveal any dust levels that might exceed the thresh old limit value (TLV).
It is obvious that good preventive maintenance must go hand in hand with effective dnst control measures if the standards recently announced by the Occupational Safety and Health Administration are to be achieved.
Establishing Safe Dust Levels
The first epidemiological study of the effects of asbestos dust on work ers was reported in 1930.1 From that time on, it. was generally recog nized in industry that asbestosis serious enough to interfere with respiratory or cardiovascular func tions could be prevented by reduc ing dust levels to a specified TLV.
The American Conference of Governmental Industrial Hygienists (ACGIH) set the industry's first standard in 1938 by establishing a TLV of five million particles per cubic foot. Independent research supported by the Johns-Manville Corporation concluded at about the same time that a TLV of one mil lion fibers, 10 microns or longer, per cubic foot would be an ade quate level for safe occupational exposure,
.In 1961, the ACGIH established a new standard with a TLV of 12 asbestos' fibers, five microns or longer, per cubic centimeter, and this was later modified--(in 1970) by reducing the time-weighted aver age to five fibers per cubic centi meter, with a maximum of 10 fibers per cubic centimeter at any one time.
This standard was adopted as a temporary -measure in 1972 by OSHAdminxstration, and it is the present accepted level. However, on
Specially-treated, lint-free asbestos tex tile material with "locked-in" fibers Is ' pulled onto table for marking, cutting of patterns. (Photo: courtesy RaybesfosManhaftan).
August 1973, NATIONAL SAFETY NEWS
July 1, 1976, a new standard is scheduled to go mto effect that will reduce the TLV to only two asbes tos fibers, five microns or longer, per cubic centimeter on a timeweighted average.
Specifically, OSHA's current per missible level is five fibers per milli liter greater than five microns in length for an eight-hour time-weight ed average air-home concentration. This may be increased to 10 sucb fibers per milliliter for no more than 15 minutes per hour, up to five hours per eight-hour day. Such deter mination shall be by the membrane filter method at 400 to 450 times magnification (4 millimeter objec tive) phase contrast illumination. Imminent danger situations are generally not applicable. Any ex posure greater than permissible levels for unprotected or improperly prqtected workers is considered a serious violation.12
How is It Measured?
Asbestosis dust will be collected with a personal sampling pump, Fibers will be counted microscopic ally at 400-450 magnification using phase contrast illumination.
OSH Act Regulations
On July 7, 1972, OSHAdministration issued standards regulating asbestos dust exposures. These oc cupational standards deal with:
Permissible concentrations of asbestos fibers;
Methods of compliance;
Warning signs and labeling of potentially dangerous products;
Monitoring of dust levels;
Medical examinations for em ployees;
Recordkeeping by employers. These standards have one basic purpose -- to protect employees from exposure to potentially hazard ous amounts of asbestos dust in their workplace,
The major obligations placed on employers, and industry in general, by the standards can be summed up as follows;
1) The employer shall maintain a healthy workplace, making sure
August 1373. NATIONAL SAFETY NEWS
Prime method of cotton dust control is the bag house type collector, as shown here outside plant.
that no employee is exposed to con centrations of air-borne asbestos fiber in excess of established limits;
2) Where the exposure limits are exceeded, the employee shall be notified in writing of the situation by his employer and shall be in formed of corrective measures be ing undertaken to reduce his ex posure to a safe level;
3) Engineering controls and the implementation of safe work prac tices are the only approved perma nent methods of correction;
4) While corrective measures are being instituted, the employee shall be protected by other means, such as tire wearing of an approved res pirator provided by bis employer, or by job rotation;
5) The use of respirators or shift rotation to achieve control is not permitted except during the time re quired to install engineering controls or implement safe work practices; in situations where such controls or practices are not technically feasible; and in emergencies;
6) No employee shall he assigned to a task requiring the use of a respirator if his most recent yearly medical examination indicates that he would be unable to function properly while wearing one, or if the wearing of a respirator would endanger the employee's health or safety, or that of another workman on the job;
7) Special protective clothing
change rooms, and separate clothes lockers shall be provided for em ployees in certain situations;
8) The personal and environ mental 'monitoring of a workplace shall he conducted by the employer to assure that the standards are being met; employees shall have access to the results of the monitoring of their jobs;
9) Warning signs shall he posted at entrances to areas where dust levels are in excess of th standard;
10) Caution labels shall be placed on any finished asbestos-con taining products that are likely to release fiber in excess of the stand ard during handling, application, or fabrication;*
11) The employer shall provide yearly medical examinations for em ployees exposed to concentrations of asbestos dust, and pre-employ ment and termination medical exams also are required;
12) Upon request, an employee's medical record will be made avail able to his family physician.
'Editor's N ote; Manufacturers and processors of apparel made of as bestos-based textile fabrics are not re quired to identify such products with caution labels, because such asbestos is "locked" into the fabric through sealants or other sophisticated pro cesses. Several such patented methods of locking-in the asbestos 'have been developed, thus minimizing or elimi nating raveling.
59
Vr ` Other)Requirements included in
J* ' the standard are: *^"1'
.
Where respirators are perjnit-
, '
ted, they must be selected from
among types approved by the U.S.
Bureau, of Mines or certified by the
'National Institute for Occupational
Safety and Health' (N IO SH );
No asbestos cement, mortar, coating, grout, plaster, or similar material containing asbestos can be removed from, shipping bags or their containers without being either wet ted, enclosed, or ventilated;
Insofar as practicable, asbestos must be handled, mixed, applied, removed, cut, scored, or otherwise . - worked in a wet state to reduce fiber emissions unless this would dimin ish the usefulness of the product;
Hand tools that may produce or release asbestos fibers in excess of the limits must be provided with local' exhaust ventilation systems;
External work surfaces must be kept free of excessive accumula tions of asbestos fiber;
Waste must be collected in sealed impermeable bags or other closed, impermeable containers.
The National Institute for Occu pational Safety and Health (NIOSH) re c e n tly conducted environmental
surveys, in some 30 plants manu facturing asbestos cement pipe, fric-
tion materials,, insulating materials, and textiles. In addition, workers in 12 plants were given medical examinations, including X-rays, and pulmonary function tests to show any indication of lung disease. In formation was also recorded on each worker's occupational, smok ing, and respiratory disease history.
On March 30, 1973, Environ mental Protection Agency Adminis trator William D. Ruckelshaus set national emission standards for three hazardous air pollutants -- asbes tos, beryllium, and mercury.*
These three pollutants' axe the first to he designated as hazardous to health under the Clean Air Act amendments of 1970, The act de fines hazardous .air pollutants as those that "may cause, or contribute to, .an increase in mortality, or an increase in serious irreversible or incapacitating reversible illness."
The "hazardous to health" desig nation requires EPA to set national emission standards for the affected `air pollutants.
The hew asbestos standards pro hibit visible emissions from asbes tos mills, selected manufacturing operations, and spray-on applica tions. The use of asbestos tailings for roadway surfacing generally is prohibited. Certain work practices are specified for the dmolition of buildings in order to control asbes tos emissions. These practices gen erally prohibit the dropping of as bestos debris from buildings and
Gloves and mittens are a major item of protective equipment utilizing asbestos. Special treatment of asbestos fabric assures "locklng-ln" of fibers, preventing fraytpg and unraveling, Such treatment' obviates any need to label the product as a possible
f f S B health' hazard. Asbestos material so treated meets O SH A ct standards as set forth In SgSjSKii".ithe fed eral Register, Vol. 37, No.. 110, dated June 7, 1972, (Pbotoi courtesy of
.Wheeler Protective Apparel, Inc.).
,
require the wetting of asbestos ma terials before removal. The demoli tion standards apply to all struc tures except homes and apartment buildings with four units or less. --
End.
REFERENCES
1. Merewether, E.R.A., "The Oc currence of Pulmonary Fibrosis and Other Pulmonary Affections in As bestos Workers," Journal of Indus trial Hygiene, Harvard School of Pub lic Health, Cambridge, MA 02100, Vol. 12, No. 5, 1930.
2. The Target Health Hazards, U.S. Department of Labor, Oc cupational Safety' and Health Ad ministration, Washington, DC 20210.
3. Environmental News, U.S. En vironmental Protection Agency, Washington, DC 20460, .March 30, 1973.
BIBLIOGR APHY
Criteria fo r o . Recommended Stan dard . . . Occupational Exposure to A s bestos. U .S. Department of Heaifh, .Edu cation, and Welfare, Public Health Serv ice, Health Services and Mental Health Administration, National Institute for Occupational Safety and Health, W ash ington DC 20000.
A ccident Prevention Manual for In dustrial O perations, 6th Edition, 1972. National Safety Council, 425 N. Michi gan Ave., Chicago 60611, 1,654 pp.
" Excerpts From the Criteria Document, Recommendations for an Asbestos Stan dard," Journal of Occupational M edi cine, Industrial Medical Association, Mayo Publications, 4936 Highland Ave., Downers Grove, IL 60515, Vol. 16, No, 4, April 1973.
"Excerpts From 'Standard for Expo sure to Asbestos Dust1" Jou rn al of O c cupational Medicine, Industrial Medical Association, 4936 Highland Ave., Down ers .Crave, IL 60515, Vol. 16, No. 4, April 1973.
Sargent, E. Nicholas, M.D,, George Jacobson, M.D., and Evelyn E. W ilkin son, M.D., "Diaphragmatic Plbvrai Cal cification Following Short Occupational Exposure to Asbestos," The Am erican Jo u rn a l of Roentgenology, Radium Ther a p y a n d Nuclear Medicine, American Roentgen Ray Society, American Radi um Society, 301 E. Lawren'ce Ave., Springfield, IL 62703, Vol. 115, No. 3, July 1972, pp. 473-478.
Section 1910.93a, "Asbestos Dyst," Self-Evaluation Checklist/Based on O SH A Sta n d a rd s, General Industry-- Part 1910, Subpart G , , Health and Environment. 1972. National Safety Council, 425 N. Michigan Ave., Chicago 60611,' (NSC Stock No. 115.1 8-0093a).
August 1973, NATIONAL SAFETY NEWS