Application of occupational exposure limits to unusual work schedules.
Am Ind Hyg Assoc J 1977 Nov; 38(11):613-621
A model for applying occupational exposure limits to unusual work schedules based on the OSHA regulatory standards was described. Body burden curves for normal and nonnormal exposures had characteristic peaks, residuals, and average body burdens. The model involved adjusting the occupational exposure limits for industrial air contaminants to unusual work schedules using peak body burden to predict equal protection. The equations for peak body burden were fitted to a one compartment model incorporating biological uptake and excretion mechanisms. The model was tested for a normal work week, a work week of four 10 hour days, a work week of three 12 hour days, and a single 40 hour shift per week. The peak body burden for substances with short half lives was attained quickly such that no modification of the OSHA limits was necessary for modified work schedules. The adjustment factor was proportional to the number of exposure hours for substances with long half lives in the body. The adjustment factor varied with the half life for substances of intermediate half lives. The model was applicable to particulates, reactive gases and vapors, and inert gases and vapors. The authors note that the predictive power of the model is limited by the limitation of the one compartment analysis.
NIOSH-Publication; NIOSH-Grant; Worker-health; Regulations; Occupational-hazards; Workplace-studies; Air-contamination; Respiratory-irritants; Occupational-exposure; Airborne-dusts; Air-sampling
American Industrial Hygiene Association Journal
Environmental Sciences & Engr Univ of North Carolina Dept of Environ Scis & Engr Chapel Hill, NC 27514