Accession Number : ADA311669

Title :   A Model To Estimate A Worker's Exposure to Spray Paint Mists.

Descriptive Note : Doctoral thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH

Personal Author(s) : Carlton, Gary N.

PDF Url : ADA311669

Report Date : 1996

Pagination or Media Count : 199

Abstract : Although local exhaust ventilation reduces exposure to airborne contaminants, current design methodology is limited because the relationship between exposure and ventilation is seldom known for a specific industrial operation. This research addressed this deficiency by introducing the notion of an empirical-conceptual model. These models relate exposure to ventilation through various process parameters responsible for the generation and transport of contaminants. To illustrate the modeling technique, an empirical-conceptual model of a spray painting task was developed. A conceptual model described three processes that determine the exposure: droplet formation, droplet transfer, and droplet transport. Each process was examined and important factors which characterize the processes identified. These factors were then grouped into four dimensionless variables using dimensional analysis. A laboratory set-up used a mannequin, flat plate and spray nozzle in a wind tunnel to find the functional relationship among these variables. The model indicates worker orientation to the freestream has a significant influence on breathing zone concentrations. The magnitude of the dimensionless quantity consisting of nozzle pressure, worker height, liquid viscosity, and freestream velocity determined in which orientation the concentration was higher. The influence of process parameters on the breathing zone droplet size

Descriptors :   *EXPOSURE(GENERAL), *WIND TUNNEL TESTS, *PAINTS, *SPRAYS, *SPRAY NOZZLES, VELOCITY, METHODOLOGY, INDUSTRIES, SIZES(DIMENSIONS), MODELS, LIQUIDS, AIRBORNE, VENTILATION, ORIENTATION(DIRECTION), ESTIMATES, DROPS, TRANSPORT, OPERATION, NOZZLES, CONTAMINANTS, LABORATORIES, PERSONNEL, EXPOSURE(PHYSIOLOGY), RESPIRATION, WORKLOAD, FREE STREAM, VISCOSITY, HEIGHT, WIND TUNNELS, MIST, RESPIRATORS.

Subject Categories : Pumps, Filters, Pipes, Tubing, Fittings & Vlvs
      Fluid Mechanics

Distribution Statement : APPROVED FOR PUBLIC RELEASE