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The National Institute for Occupational Safety and Health (NIOSH) investigators compared methods for collecting personal breathing zone (PBZ) air samples for particulates during abrasive blasting at a shipyard. Abrasive blasting is the cleaning or finishing of surfaces by the use of an abrasive carried in a strong current of air. The U.S. government has provided regulatory requirements and guidelines for ventilation, enclosures, and personal protective equipment during abrasive blasting [NIOSH 1987; OSHA 2012a]. However, current Occupational Safety and Health Administration (OSHA) sampling and analytical methods can overestimate worker exposures to airborne metals and other particulate contaminants during abrasive blasting [NIOSH 1994; NIOSH 1998; OSHA 2012b]. Shielding the 37-mm filter cassette inlet to exclude non-inhalable particles, mounting the PBZ air sampler behind the employee's head to protect the sampler from rebounding abrasive materials, and using the Institute of Medicine inhalable dust sampler, have been proposed as alternatives to assess exposure. All were found to be impractical or ineffective in abrasive blasting environments [NIOSH 1994, 1998]. Sampling simultaneously inside and outside the employees' abrasive blast hood has shown that the lower air concentrations inside the abrasive blast hood produce less overloading of the 37-mm cassettes [NIOSH 1998]; however, sampling inside PPE is not accepted by OSHA for compliance purposes [OSHA 2012a, b]. Aizenberg et al. [2000] used a Button Aerosol Sampler® (BAS) (part number 225–360, SKC Inc., Eighty Four, Pennsylvania) with a prototype shield to evaluate PBZ exposures during abrasive blasting operations. The investigators reported that the protective shield prevented non-inhalable particles from overloading the filter and did not interfere with sampling smaller particles; however, the researchers did not determine whether the prototype protective shield altered the collection efficiency of the BAS. Following the Aizenberg et al. [2000] study, SKC Inc. designed a snap-on dome-shaped stainless steel protective secondary shield for use with the BAS when sampling during abrasive blasting (Abrasive Blasting Sampler for Heavy Metals kit, part number 225–367, SKC Inc., Eighty Four, Pennsylvania). This shield differed in size, shape, and screen opening from the prototype screen tested by Aizenberg et al. [2000]. Due to uncertainty about possible effects that shielding may have on the performance characteristics of the BAS, the objectives of this evaluation were to: (1) compare the commercially available BAS (with and without the shield) with the conventional 37-mm cassette sampler in an abrasive blasting environment and (2) evaluate whether the protective shield designed for the BAS prevented inertia-driven particles from entering and possibly overloading the sampler [NIOSH 2012a].