The Beryllium Quandary
Will Lower Exposure Limits Spur New Developments in Sampling and Analysis?
EDITOR'S NOTE: In August, OSHA issued a proposed rule that would lower its permissible exposure limit for beryllium from 2 µg/m3 to 0.2 µg/m3 (see related article). The article below, which originally appeared in the August 2013 issue of The Synergist, discusses issues related to sampling and analysis of beryllium.
Sampling and analysis of beryllium in the workplace can be more challenging than for many other metals. For starters, the occupational exposure limits for beryllium tend to be in the microgram or sub-microgram per cubic meter range, rather than in the milligram range. Some forms of beryllium, especially beryllium oxide, are not fully dissolved in many commonly used sample preparation methods. And, in many cases, interpreting results for beryllium samples is difficult as well, particularly if most results come back below the laboratory’s reporting limit and you don’t have the luxury of collecting enough samples for a nonparametric statistical treatment.
At the time this article was written, new rulemakings were under consideration at OSHA and the U.S. Department of Energy (DOE) that would propose changes to occupational exposure limits for beryllium. Given these developments, now is a good time to review the tools and methods available to IHs for assessing beryllium air and surface contamination in the workplace—what’s new and different, and what’s tried and true. LIMIT VALUES Limit values and action levels for beryllium vary around the world. Table 1 details the current limit values in various jurisdictions. While many countries use the same value as OSHA’s current permissible exposure limit (PEL) of 0.002 mg/m3 TWA, some jurisdictions have lower limit values for airborne beryllium particulate matter. However, the DOE regulation (10 CFR 850) also has action levels for surface contamination: 0.2 micrograms per 100 cm2 for free release from beryllium work areas, and a higher action level, 0.003 mg/100 cm2 for housekeeping within beryllium work areas. Although most practitioners think only in terms of air sampling, tens of thousands of surface samples for beryllium are collected each year, mostly, but not entirely, at DOE sites.