The National Institute for Occupational Safety and Health (NIOSH), working under an interagency agreement with the Office of Regulatory Analysis of the Occupational Safety and Health Administration (OSHA), conducted a study to survey occupational exposures to beryllium and to document engineering controls and work practices affecting those exposures. The performance of a thorough industrial hygiene survey for a variety of individual employers provides valuable and useful information to the public and employers in the industries included in the work. The principal objectives of this study were: 1. To identify and describe the control technology and work practices in use in operations associated with occupational exposures to beryllium, as well to determine additional controls, work practices, substitute materials, or technology that can further reduce occupational beryllium exposures. 2. To measure full-shift, personal breathing zone, particulate exposures to beryllium. These samples provide examples of exposures to beryllium among workers across the many industries where beryllium is encountered. These exposure data, along with the control data described above, provide a picture of the conditions in the selected industries. This site visit was conducted on June 21-23, 2004, by NIOSH researchers from the Engineering and Physical Hazards Branch, Division of Applied Research and Technology, in Cincinnati, Ohio. Occupational exposure to beryllium occurs at places where the chemical is mined, processed, or converted into metal, alloys, and other chemicals. Workers engaged in machining metals containing beryllium, recycling beryllium from scrap alloys, or using beryllium products may also be exposed to higher levels of beryllium. The number of workers exposed to beryllium or beryllium compounds has been estimated to be 21,000 (ATSDR 2002). There is a need to understand the nature of these beryllium exposures, what is causing the exposures, and what steps are being taken or could be taken to reduce the exposures (e.g., engineering controls, work practices, and personal protective equipment). Beryllium has been reported in mineral slag abrasives, including coal slag (Stettler et al. 1982, NIOSH 1998, Meeker et al. 2006). Stettler et al (1982) reported the results of the analysis of 12 coal slags; 9 contained beryllium, ranging from 7-48 micrograms per gram (µg/g). Meeker et al. (2006) found beryllium in clean coal slag samples, and found task-weighted personal exposures outside of the blasters' personal protective equipment that ranged from 2.5-9.5 micrograms of beryllium per cubic meter of air (µg/m3). They reported a geometric mean beryllium exposure of 5 µg/m3. NIOSH (1998) evaluated coal slags [including Black Beauty(TM)] with and without the addition of a dust suppressant compound and reported a geometric mean airborne concentration of 2.040 milligrams (mg)/m3 for the entire coal slag category tested. The OSHA general industry standard sets a permissible exposure limit (PEL) at 2 µg/m3 for an 8-hour time-weighted average (TWA), or 5 µg/m3 of beryllium in air, not to exceed 30 minutes at a time (29 CFR 1910.1000). OSHA also requires that workers in general industry should never be exposed to more than 25 µg/m3 of beryllium in air, regardless of how short the exposure. The OSHA PEL for the construction industry for beryllium and beryllium compounds (as Be) is 0.002 mg/m3 (2 µg/m3) as an 8-hour TWA (29 CFR 1926.55). The current NIOSH Recommended Exposure Limit (REL) for beryllium is 0.5 µg/m3, while the current American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV) is an 8-hr TWA of 2 µg/m3, and a Short Term Exposure Limit (STEL) of 10 µg/m3 (NIOSH 1997, ACGIH 2001). The OSHA PEL for the construction industry for particulates not otherwise regulated, total dust organic and inorganic is 15 mg/m3, 8-hour TWA (29 CFR 1926.55). Surface sampling is not appropriate for estimating exposures but is useful for evaluating process control and cleanliness and for determining suitability for release of equipment. There are no surface contamination regulations applicable to the use of beryllium in general industry or construction. However, a useful guideline is provided by the U.S. Department of Energy (DOE), where DOE and its contractors are required to conduct routine surface sampling to determine housekeeping conditions wherever beryllium is present in operational areas of DOE/NNSA facilities (10 CFR 850). Those facilities must maintain removable surface contamination levels that do not exceed 3µg/100 cm2 during non-operational periods (10 CFR 850). The DOE also has release criteria that must be met before beryllium-contaminated equipment or other items can be released to the general public or released for use in a non-beryllium area of a DOE facility. These criteria state that the removable contamination level of equipment or item surfaces does not exceed the higher of 0.2 µg/100 cm2 or the level of beryllium in the soil in the area of release. Removable contamination is defined as "beryllium contamination that can be removed from surfaces by nondestructive means, such as casual contact, wiping, brushing, or washing" (10 CFR 850).