Average arc times ranged from 20 to 25% of the total sampling time. The boiler room average personal breathing zone sample total particulate concentrations ranged from 4.73 mg/m(3) to 5.90 mg/m(3), Fe concentrations ranged from 0.48 to 0.85 mg/m(3), and Mn concentrations ranged from 0.06 to 0.16 mg/m(3). Breezeway average personal breathing zone sample total particulate concentrations ranged from 2.89 mg/m(3) to 4.38 mg/m(3), Fe concentrations ranged from 0.53 to 0.63 mg/m(3), and Mn concentrations ranged from 0.10 to 0.12 mg/m(3). Samples were collected and analyzed for total particulate following NIOSH Method 0500 and for select metals following NIOSH Method 7300. The study is unique in that one welder was evaluated under high production conditions for 2 days at two different welding locations: a boiler room and a breezeway. The resulting breathing zone (near field) and area (far field) welding fume concentration data were applied to the two-zone model for the purpose of determining field-derived personal exposure emission (generation) rates during actual welding work. N2 - This study assessed a professional pipefitter/welder performing shielded metal arc welding on carbon steel under field conditions. JF - Journal of occupational and environmental hygiene T1 - Two-zone model application to breathing zone and area welding fume concentration data. This study emphasizes the need for field-derived welding fume generation rates and showed the personal breathing zone and area sample concentrations can be described by the two-zone model in a way that may help the industrial hygienist estimate exposures. The field-based generation rates were considerably lower than laboratory-derived published emission rates of between 280 and 650 mg/min for TP. The average generation rate in the breezeway was 40.0 mg/min for TP, 6.6 mg/min for Fe, and 1.2 mg/min for Mn. The average generation rate in the boiler room was 39.2 mg/min for TP, 6.4 mg/min for Fe, and 1.3 mg/min for Mn. The steady-state form of the two-zone model was applied to long-term and short-term sample total particulate, Fe, and Mn concentrations obtained during welding in the boiler room and breezeway. Both tracer gas and anemometer techniques were used to estimate ventilation of the boiler room. Recommendations include keeping worker blood ZPP concentrations from rising excessively and improving the respirator program.This study assessed a professional pipefitter/welder performing shielded metal arc welding on carbon steel under field conditions. Maintenance and janitorial personnel have the greatest potential for lead exposure. The authors conclude that there is no definite pattern in the company blood lead/ZPP data. Improper use of respirators was observed. Urine arsenic concentrations were within the normal range. No pattern of medically unexplained discrepancies between blood lead and ZPP concentrations was detected. Arsenic, stibine, and antimony exposures were below the OSHA standards. Highest exposures were among janitor and maintenance workers. Eleven percent of 675 lead breathing zone samples exceeded the OSHA standard of 50 micrograms per cubic meter. The company respirator program was reviewed. Urine samples were obtained from 49 workers and analyzed for arsenic. Company lead monitoring and blood lead data was reviewed. Concern was expressed about apparent physiological discrepancies between blood lead and zinc-protoporphyrin (ZPP) concentrations in certain workers. The evaluation was requested by the union to assess exposures to lead (7439921) and other substances. Environmental and breathing zone samples were analyzed for inorganic arsenic (7440382), stibine (7803523), antimony (7440360), and sulfuric-acid (7664939) at Johnson Controls, Incorporated (SIC-3691), Owosso, Michigan in November, 1983 and April, 1984.
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