title: Tracer gas evaluations of push-pull ventilation system performance.
abstract: A push-pull ventilation system is effective for hazardous material exhaustion. Although a push-pull ventilation system has advantages over a local exhaust hood, some laborious adjustments are required. The pertinence of the adjustments is uncertain because it is difficult to evaluate the performance of a push-pull ventilation system quantitatively. In this study, a measurement of the capture efficiency of a push-pull ventilation system was carried out by means of a tracer gas method. The capture efficiency decreased to 39.3-78.5% when blockage material, a dummy worker and a cross draft, were set in the ventilation zone, but the efficiency was 95.1-97.9% when the cross draft was stopped. The results suggest that the uniform flow of a push-pull ventilation system will detour a blockage and the performance of the system will not be reduced unless a cross draft disturbs the uniform flow.
authors.affiliation: National Institute of Occupational Safety and Health, Tama-ku, kawasaki, Japan.
authors.forename: Jun
authors.initials: J
authors.lastname: Ojima
mesh_terms: D005740:Gases / Q000032:analysis*; D015386:Hazardous Substances; D007564:Japan; D014691:Ventilation / Q000379:methods / Q000592:standards*
chemical_list: D005740:Gases; D015386:Hazardous Substances