The impact of boundary layer separation on local exhaust design and worker exposure.
George-DK; Flynn-MR; Goodman-R
Appl Occup Environ Hyg 1990 Aug; 5(8):501-509
The phenomenon of boundary layer separation, an important factor in determining a worker's breathing zone concentration, was investigated. Flow visualization and tracer gas studies were conducted in a wind tunnel using a mannequin. The mannequin's breathing zone concentration was estimated using a simple conceptual model based on mass transport by vortex shedding. An empirical model which relates the measured concentration to the distance from the source to the breathing zone for the situation when the contaminant is released downstream in a uniform flow was developed. The results suggested that in situations where a worker is immersed in a uniform flow, a higher level of control may be achieved by standing to the side of the workpiece rather than with the back to the flow. The authors also suggest that caution should be displayed when extrapolating to real life situations.
NIOSH-Publication; NIOSH-Grant; Control-technology; Exhaust-ventilation; Airborne-particles; Industrial-factory-workers; Breathing-zone; Toxic-materials; Air-contamination; Smoke-inhalation; Industrial-ventilation
Environmental Sciences & Engr University of North Carolina Rosenau Hall 201H Chapel Hill, NC 27514
Applied Occupational and Environmental Hygiene
University of North Carolina Chapel Hill, Chapel Hill, North Carolina