Document RjDRVjdb1g0JLb8BngxXZjB08

PLAINTIFF'S EXHIBIT MON-2388 * *r * * ASiOClAtlOM HYGIENIC GUIDE SERIES Hygienic Guile Series Asbestos I. Hvgiemc standards A." RECOMMENDED MAXIMUM AT MOSPHERIC CONCENTRATION (S hoursl: 5 million particles per cubic foot of air (MPPCF).' 1.1) Basis for Recommendation: Experi ence in industry,* * ' " u and ani mal experiments.1,' B. SEVERITY OF HAZARDS: (1) Health: Long continued inhalation of asbestos dust results in a form of pneumoconiosis known as asbestosis. The primary effect of inhala tion is an interstitial pulmonary fibrosis. The disease is characterized bv asbestos bodies in the lungs and sputum. Based on roentgenological examinations, asbestosis can be clas sified as minimal, moderate, and advanced. It is a serious disease in some instances, but more frequently it remains nondisabling for many years, even without appreciable symptoms, as long as some other serious disease does not supervene to cause death.* Chief symptoms of advanced asbestosis are variable cough, dyspnea, substernal chest pains, decreased chest expansion, weakness, emaciation, clubbed fin ger tips, and curved fingernails. Any appreciable decrease in the amount of asbestos dust in the breathing atmosphere will cause a decrease in the incidence and seventy of asbestosis. Individual suceptibilitv vanes.* There have been reports of an increased incidence of lung can cer in persons with asbestosis.1 (2) Fire: None. C. SHORT EXPOSURE TOLERANCE: Not applicable: II. Significant Properties A fibrous magnesium calcium silicate which occurs in various combinations as white, greyish or greenish masses, either compact or of long silky fibers, flax-like and readily separated. About 95% of commencal asbes tos is chrysotile, which is derived from serpentine, and is a hydrous magnesium silicate containing from 12 to 14 per cent water of crystallization. III. Industrial Hygiene Practice A. RECOGNITION: The spinning and weaving of asbestos, in combination with other textiles for fire proof and heat resistant cloth, results in dust exposure. It may be used by itself or combined with other materials for valve packings, gaskets, boiler ls.gging and pipe cover ing, protective clothing, shielding ma terials, and as automotive brake linings. In the building industry it is used in the manufacture of asbestos cement products, heat insulating, and fire proofing materials. B. EVALUATION OF EXPOSURES: As bestos dust may be sampled with the electrostatic precipitator or by the impinger methed using alcohol or alcohol and water, as the collecting medium,* * and dust counts made by the standard light field technique.' The recommended maximum atmospheric concentration of 5 MPPCF is based upon the impinger sampling procedure. C. RECOMMENDED CONTROL PRO CEDURES: Prevention of asbestosis depends entirely upon preventing ex posure to concentrations of dust siiffi- LAM021546 6113 18242 BCC~S36 ciently high to jiroduce the characteris tic reaction. Enclosure or local exhaust ventilation are the principal means of dust control. U. 8. Bureau of Mines ap proved dust respirators may be worn as protection for some operations. IV. Specific Procedures A. FIRST AID: None. B. SPECIAL MEDICAL PROCEDURES: (1) Preplacement: Clinical and radio- graphic chest examinations prior to job assignment. 12) Periodic: Exposed personnel should have periodic clinical examinations for signs and symptoms of asbestosis. These should include exami nation of the sputum for asbestosis bodies, and chest x-rays of good quality. (3) Treatment: No satisfactory treat ment other than removal from ex posure and therapy for any com plicating infection. V. Literature References 1. American Conference of Governmental Industrial Hygienists: AMA Arch, of lnd. Health, 16: 261, 1957. 2. Cartier, Paul: AAfA Arch, oj lnd. Health, 11: 204, 1955. 3. Doll, R.: Brit. J. Ind. Med., IS: 8, 1955. 4. Dreesen, W. C., et al: Public Health Bulletin No. 241, Supt. of Doc., Wash ington, D. C., 1938. 5. Drinker, P. and Hatch, T.: Industrial Dust. McGraw-Hill Book Co., Inc., New York, 1954. 6. Fairhall, Lawrence T.: Industrial Toxicology. The Williams & Wilkins Co., Baltimore, Md., 1957. 7. King, E. J., et al: Thorox I, p. 188, 1946. 8. Lynch, K. M.: AMA Arch, of Ind. Health, 11: 185, 1955. 9. McPheeters, S. B.: J. Ind. Hyg. & Tax., 18 : 229, 1936. 10. Page, R. T. and Bloomfield, J. J.: Pub. Health Repts. SS: 1713, 1937. 11. Patty, Frank A.: Industrial Hygiene and Toxicology, Vol. 1. Interscience Publishers, Inc., New York, 1948. 12. Smith, K. W., AMA Arch, of Ind. Health, IS: 198, 1955. 13. Vorwald, A. J., et al: AMA Arch. Ind. Hyg. and Occup. Med. 3: 1, 1951. Because oj space limitations, it is impossible to list all methods of exposure evaluation. The selections have been made on the basis of current usage, reliability, and applicability to the usual industrial type oj exposure. Any specific evaluation and/or control problem util involve professional judgment. This can best be done by professional industrial hygiene personnel. Respiratory protective devices are commercially available. Their use, however, should be confined to emergency or intermittent exposures and not relied upon as primary means of hazard control. A relative scale is used for rating the severity of hazards: nil, low, moderate, high, and extra hazardous. Hycienic Guides Committee William E. McCormick. Chairman Hervey B. Elkins. Ph D. David W Fassett. M.D. Clyde M. Berry. Ph.D. H. W. Speicher William B. Harris Melvin W. First. Sc.D. H. E. Stokincer. PhD. Paul D. Halley Edward V. Henson. M.D. 6113 18243 (Ipr. US-% BGG^S97 LAM021547