title: Contaminant concentration reduction: general ventilation versus local exhaust ventilation.
abstract: General ventilation has often been proposed as a supplement to or replacement of local exhaust ventilation to reduce the concentration of contaminants in the workplace. The use of four air changes and ten air changes per hour of general ventilation to reduce contaminant concentration is studied. The concentration reduction is estimated theoretically. The first cost of general ventilation and the operating costs are estimated for a typical situation. These costs are compared to those of local exhaust ventilation. The general ventilation effect of local exhaust points, in the vicinity of the dust sources, is analyzed in comparison to the effect of general ventilation in an entire plant. The effect of general ventilation on dust counts is presented.
mesh_terms: D000393:Air Pollutants; D000395:Air Pollutants, Occupational; D003365:Costs and Cost Analysis; D004391:Dust / Q000517:prevention & control*; D014691:Ventilation
chemical_list: D000393:Air Pollutants; D000395:Air Pollutants, Occupational; D004391:Dust