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AMMONIA The maximum t set by the Navy for continuous exposure in
<br /> submarines is 25 ppm.�161
<br /> CAS: 7664-41-7 NIOSH concludes that a TWA standard is inappropriate for
<br /> NH3 ammonia, and recommends a five minute ceiling of 50 ppm as a
<br /> workplace environmental standard.181
<br /> TLS/-TWA, 25 ppm ( = 18 mg/m3) It is the judgment of the Committee that the time-weighted aver-
<br /> TLV-STEL, 35 ppm ( = 27 mg/ml) age exposure is significant,and should be maintained at a lower level
<br /> than is permissible for brief excursions. The fact that continuous,
<br /> Ammonia is a colorless gas with a sharp intensely irritating odor. 244iour exposure produces effects not observed from considerably
<br /> It is lighter than air and easily liquefied by pressure. Physiochemical higher exposures of the occupational type"" can be considered as
<br /> properties include: possibly supporting this conclusion.
<br /> A time-weighted average TLV of 25 ppm has been selected to pro-
<br /> Molecular weight: 17.03 tect against irritation to eyes and the respiratory tract and minimize
<br /> Specific gravity: 0.77 at 0°F; 0.6819 at boiling point discomfort among uninured workers. It is suggested that the STEL,
<br /> Boiling point: -3.5°C however, be set at 35 ppm.
<br /> Freezing point: -77.7°C
<br /> Vapor pressure: liquid, 8.5 atmospheres at 20°C Other recommendations:West Germany(1974)Japan,Yogoslavia,
<br /> 50 ppm;East Germany(1973) 33 ppm; USSR(1976),Sweden(1975),
<br /> it is very soluble in water, alcohol and ether. Austrialia, Belgium, Finland, Hungary, Italy, Netherland, Poland,
<br /> Ammonia finds use .as a fertilizer as such or in compounds; Romania, Switzerland, all 25 ppm.
<br /> manufacture of nitric acid, hydrazine hydrate, hydrogen cyanide,
<br /> acrylonitrile; refrigerant; nitriding of steel; condensation catalyst for
<br /> polymers and many uses.
<br /> Henderson and Haggard"' record temporary blindness and in- References
<br /> tolerable irritation from high concentrations. Osmond et all" 1. Henderson,Y.and H.W. Haggard:Noxious Gases. Reinhold Publish-
<br /> describe severe eye damage and irriation of the glottis from exposure ing Company, New York (1927).
<br /> at high concentration. Schenker" reports that toxic doses of 2. Osmond, A.H.et al: Brit. Med. J. 3:740 (September 1968).
<br /> ammonia acutely affect cerebral energy metabolism and this effect 3. Schenker, S.J.: Clinical Invest. 46:838 (196 .
<br /> is preferentially localized at the base of the brain. Henderson and 4. Smyth H.F., Jr.:Am. Ind. Hyg. Assoc. Q. 17:45 (1956).
<br /> Haggard report the least detectable odor level to be 50 ppm but
<br /> 5. Bur.Ind.Hyg.,Detroit Dept.of Health: Unpublished reports of inves-
<br /> Smyth141 found 1 ppm detected and identified by 10 subjects. Anal- tigations, 1965-1970.
<br /> ysis of data obtained in plant surveysi51 found the limit of detection 6 Vigliani,E.C.and N.Zurlo:Thru abst.,Arch.Ind.Health 13:403(1956).
<br /> to be below 5 ppm and the complaint level to be 20-25 ppm. 7. Balhamn, T.:Acta. Physiol. Scand. Suppl. 123, pp. 1-161 (1956).
<br /> Vigliani and Zurl0i61 found irritation of the respiratory tract and 8. NIOSH:Criteria fora Recommended Standard-Occupational Exposure
<br /> conjunctivae in workers inhaling 100 ppm and 20 ppm caused com- to Ammonia. DHEW Pub. No. (NIOSH) 74-136 (1974).
<br /> plaints and discomfort in uninured workers. Dalhamn 171 found that g Industrial Biotest Laboratories:Irritation Threshold Evaluation Study with
<br /> 3 ppm NH, stopped rat respiratory tract cilia from beating. Studies Ammonia, IBT 663-03161 (March 23, 1973).Cited by NIOSH Ref.8.
<br /> of the effect on man of exposures in the 5-50 ppm range are meager 10. MacEwen,J.U.,J.Theodore and E.H.Vemot:In:Proc. 1st Annual Con-
<br /> but general field experience with a large number of workers exposed Terence on Environmental Toxicolology, Wright-Patterson Air Force Base,
<br /> to NH,from blue printing and copying machines indicates a max- OH(September 9-11, 1970), Paper No. 23,p.355.AMRL-TR-70-102.
<br /> imum acceptable concentration without severe complaints of 20-25 11. Mangold,C.A.: Investigation of Occupational Exposure to Ammonia.
<br /> ppm- Puget Sound Naval Shipyard (November 29, 1971). Ibid.
<br /> In its criteria document for ammonia, NIOSH181 cites a number of 12. Pagnotto, L.D.: Private communication (1973).
<br /> additional references indicating that concentrations as low as 50 ppm 13. Dalhamn,T.and J.Sjoholm:Acta Physiol.Scand. 58:287(1963). Cit-
<br /> are moderately irritating or disagreeable, but that workers generally ed by NIOSH ref. 8.
<br /> become inured to these levels.19"' Later studies by Dalhamn on the 14. Landall, H.D.and R.G. Hermann:Arch. Ind. Hyg. Occup. Med. 1:36
<br /> effects of ammonia on ciliary activity, in rabbits, showed that 100 (1950).
<br /> ppm were required in the trachea to produce a significant 15. Dalhamn,T.and L.Reid:Inhaled Particles and vapours 11,p.299.C.N.
<br /> response.i131 The discrepancy between this finding and the earlier Davies, Ed. Pergamon Pub,Co., Elmsford, New York(1967). Cited by
<br /> report on rats"' is not explained. It is noted that the average nasal NIOSH ref. 8.
<br /> retention of ammonia by human subjects was found to be 83%."41 16. Submarine Atmosphere Habitability Data Book. NAVSHIPS No.
<br /> The combined effects of ammonia and carbon particles inhaled by 250-649-1, Rev. 1. Navy Dept., Bureau of Ships (1962). Ibid.
<br /> rats were reportedly much greater than those from ammonia (or 17. Stombaugh, D.P., H.S. Teague and W.L. Roller:1.Anim. Sci. 28:844
<br /> carbon) alone.1161 (1960). Ibid.
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