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Emission of gases coming from liquid manure, especially swine wastes.
Proceedings of the VII International Congress of Rural Medicine, September 17-21, Salt Lake City, Utah. International Association of Agricultural Medicine, 1978 Sep; :194-196
Emission of gases by liquid manure was discussed. The problem of toxic gases being emitted by liquid manure in swine houses was considered. The emission of toxic gases from manure is influenced by the season of the year, type of ventilation, and feeding practices. The gases are generated by anaerobic degradation and consist primarily of ammonia (7664417), hydrogen-sulfide (7783064), mercaptans, and methane (74828). The gases usually remain dissolved in the liquid manure until the manure is disturbed. As long as there is little air movement, the layer of air over the manure contains high concentrations of the gases, but the gases do not diffuse out of the layer into the ambient air. In barns with open pits where the liquid manure moves out very slowly and its surface is not disturbed except for excrement or urine dripping onto it, very little gas development occurs. The two most common ailments from the poison gases are bronchitis and indigestion, with ammonia and mercaptan more often affecting the bronchi and hydrogen-sulfide, methanes and odor more often affecting the stomach. Procedures for reducing the concentration of toxic gases produced by liquid manure were discussed. Ventilation of the barn, daily cleaning of the stalls, using straw bedding, agitation of the liquid manure to allow for continual bacterial action, and hot fermentation of the straw/manure mixture are recommended.
NIOSH-Grant; Grants-other; Agriculture; Livestock; Liquid-wastes; Animal-products; Toxic-gases; Flammable-gases; Work-practices; Decomposition-products; Biodegradation; Emission-sources; Control-methods
Prev Med & Environmental Hlth University of Iowa Inst/agric Med & Environ Hlth Iowa Oakdale, Iowa 52319
7664-41-7; 7783-06-4; 74-82-8
Other Occupational Concerns; Grants-other
Proceedings of the VII International Congress of Rural Medicine, September 17-21, Salt Lake City, Utah
University of Iowa, Iowa City, Iowa
Page last reviewed: August 7, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division