Screening ventilation strategies for confined-space manure storage facilities.
Pesce EP; Zhao J; Manbeck HB; Murphy DJ
J Agric Saf Health 2008 Aug; 14(3):283-308
Fatalities associated with entry into on-farm confined-space manure storage facilities occur each year. The fatalities are due to asphyxiation or poisoning by exposure to high concentrations of hydrogen sulfide, methane, and carbon dioxide. Forced ventilation has been shown to be an effective way to reduce concentrations of noxious gases to levels that are safe for human entry into these storage facilities. Hydrogen sulfide (H2S) was used as an indicator gas to investigate the effectiveness of forced-air ventilation strategies for eliminating the toxic and oxygen-deficient atmosphere in confined-space manure storage facilities. This article focuses on experimental methods for identifying ventilation strategies that effectively reduce toxic gas (i.e., H2S) concentrations in a fan-ventilated confined-space manure tank to the OSHA permissible exposure limit (PEL) (H2S PEL = 10 ppm) and to 25% of the initial gas concentration. Typical H2S concentration reduction curves during forced-air ventilation were identified in the tank as well. Based on the experimental tests conducted in this research, the most promising candidate ventilation strategies were identified for this rectangular confined-space manure tank with solid, fully slotted, and partially slotted covers. In addition, based on the results of experimental tests, a field-based database was developed for future validation of computational fluid dynamics modeling protocols.
Agriculture; Agricultural-industry; Agricultural-workers; Occupational-hazards; Confined-spaces; Toxic-gases; Ventilation; Ventilation-equipment; Ventilation-systems; Air-contamination; Air-quality-monitoring; Air-treatment-equipment; Risk-analysis; Risk-factors; Storage-facilities;
Author Keywords: Confined-space manure storage facilities; Forced-air ventilation; Hydrogen sulfide; OSHA permissible exposure limit; Safety; Ventilation strategy
Harvey B. Manbeck, PhD, Department of Agricultural and Biological Engineering, 249 Agricultural Engineering Bldg., The Pennsylvania State University, University Park, PA 16802
Agriculture, Forestry and Fishing
Journal of Agricultural Safety and Health
Mary Imogene Bassett Hospital, Cooperstown, New York