Factors Affecting the Design of Local Exhaust Ventilation for the Control of Contaminants from Hand-Held Sources.
Flynn MR; Shelton WK
Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, North Carolina 1990 Feb:25 pages
Measurements were made of tracer gas concentrations in the breathing zone of a mannequin positioned in front of flanged circular exhaust hoods arranged in various configurations. The gas was generated from a hand held source. The results indicated that the mannequin was subjected to less hazardous conditions when placed to the side of the hood rather than in the conventional orientation with the source between the body and the hood. These experiments showed that there was an increase in exposure as the distance decreased between the source and the hood for small hoods. This was an unexpected finding. The authors stress the importance of considering worker practices when evaluating the effectiveness of engineering controls. Factors which determine the exposure of the individual working in the hood include the mass flow of pollutant, the source configuration and momentum, the hood air flow, the hood size and shape, the distance of the worker from the hood, and the position of the worker and source with respect to the hood.
NIOSH-Grant; Control-technology; Air-sampling; Air-flow; Exhaust-ventilation; Exhaust-hoods;
Environmental Sciences & Engr University of North Carolina Rosenau Hall 201H Chapel Hill, NC 27514
Final Grant Report;
NTIS Accession No.
Control Technology and Personal Protective Equipment; Research Tools and Approaches; Control-technology;
Department of Environmental Sciences and Engineering, University of North Carolina, Chapel Hill, North Carolina
University of North Carolina Chapel Hill, Chapel Hill, North Carolina