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Risques dus a la reaspiration des gaz d'echappoment par les moteurs en espace confine (Hazard from engines rebreathing exhaust in confined space).
Cah Notes Doc 1973 Jan; (73):471-481
The Bureau of Mines conducted a series of experiments to determine the influence of exhaust rebreathing on emissions from various gasoline and diesel engines. Tests were conducted that simulated operation of engines in nonventilated spaces as well as in spaces with partially restricted ventilation. Results of these tests showed that exhaust rebreathing can have a marked effect on exhaust emissions and thus on the composition of the air in the working space. For the case of restricted ventilation, unacceptably high (greater than 50 ppm) levels of CO in the air of the working space resulted from exhaust rebreathing rates as low as 8 percent exhaust in the engine's intake. Operation in a nonventilated space resulted in highly critical CO levels (fatal in a few minutes) at times corresponding to 1 to 3 pounds of fuel consumed per 1,000 cubic feet of space. Tests involving spaces of various sizes showed that volume of the air space per se is not important--the primary variable is fuel consumed per unit volume of air space. This paper is a translation of Bureau of Mines Report of Investigations 7757.
Mining-industry; Mining-equipment; Exhaust-gases; Diesel-emissions; Diesel-exhausts; Confined-spaces
OP; Journal Article
Issue of Publication
Cahiers de Notes Documentaires
Page last reviewed: September 2, 2020
Content source: National Institute for Occupational Safety and Health Education and Information Division