ABSTRACT
The mass size distribution of beryllium aerosols generated in the various operational areas of a typical extraction and processing plant was studied using an eight-stage impactor sampler. The total concentration of beryllium in the plant was found to be well below the threshold limit value. The mean value of mass median aerodynamic diameter of beryllium particles observed for various operations ranged from 5.0-9.5 microm. The alveolar deposition for various operational areas was estimated to be 3-5% for nasal breathing and 9-13% for oral breathing based on the International Commission on Radiological Protection (ICRP) human respiratory tract model. Deposition during oral breathing was higher than during nasal breathing by approximately a factor of two to three. This study on exposure characterization was useful for reducing the respirable fraction of beryllium aerosol by optimizing the capture velocity and improving the quality of other control measures.
Subject(s)
Air Pollution, Indoor/analysis , Beryllium/analysis , Inhalation Exposure , Occupational Exposure , Aerosols , Conservation of Natural Resources , Environmental Monitoring , Humans , Industry , Particle Size , RespirationABSTRACT
Beryllium concentrations in atmospheric particulate and soil samples in and around a Beryllium Processing Facility (BPF) have been measured. The mean air concentration level of beryllium in and around the fence line of the BPF is 0.48 +/- 0.43 ng m(-3) (n = 397) and is mostly influenced by diurnal and seasonal changes. The observed air concentration levels were well below the prescribed ambient air quality (AAQ) standard of 10 ng m(-3). The soil concentration levels of beryllium in the study area were found to be in the range of 1.42-2.75 microg g(-1). The mass median aerodynamic diameter (MMAD) of beryllium aerosols in ambient air was found to be 6.9 microm. Source identification using the Enrichment Factor (EF) approach indicates soil as the predominant contributory source for air concentrations at the site.
