Cincinnati, OH: U.S. Department of Health and Human Services, Public Health Service, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, HETA 2008-0275-3146, 2011 Nov; :1-31
In August 2008, NIOSH received an HHE request from employees at an indoor small arms firing range concerned about lead exposure and indoor environmental quality. We met with employer and employee representatives and observed work processes, practices, and workplace conditions on January 12-13, 2009. We also evaluated the ventilation systems, measured airflow in the firing range, and spoke with employees. On the basis of this initial visit, we recommended installing a new ventilation system capable of delivering the NIOSH-recommended airflow. The follow-up site visit to collect air and surface lead samples was scheduled for March 2009; however, we delayed this site visit until December 2009 because of plans to install a new ventilation system in the firing range. This renovation was still delayed by the time of the December site visit, so we offered instead to collect air and surface samples to assess lead exposure before and after installation of the new ventilation system. This report only describes conditions before installation of the new ventilation system. On December 8-10, 2009, we collected PBZ air samples on firing range instructors (instructors), shooters, and the hazardous materials technician at the facility. General area air samples, floor vacuum samples, and surface wipe samples were collected in areas around the facility. We also repeated the airflow measurements in the firing range. The lead concentrations from PBZ air sampling on instructors ranged from ND- 96 microg/m3 over the sampling period (calculated 8-hour TWAs were ND- 83 microg/m3); one instructor's calculated TWA exposure (83 microg/m3) exceeded applicable OELs for an 8-hour TWA. For shooters, PBZ lead exposures ranged from 42 - 340 microg/m3 over the sampling periods (calculated 8-hour TWAs were 10 - 99 microg/m3). One shooter who repeated a portion of the qualification had an exposure of 99 microg/m3; this exceeded applicable OELs for an 8-hour TWA. The hazardous materials technician's lead exposure was 3,200 microg/m3 over the sampling period (calculated 8-hour TWA was 670 microg/m3), exceeding the applicable OELs for an 8-hour TWA. The PBZ air sample was collected outside the loose-fitting PAPR that the hazardous materials technician wore while sweeping, vacuuming, and changing exhaust air vent filters in the firing range. Floor vacuum and surface wipe sample results showed the presence of lead on work surfaces. This suggests that workplace contamination was being tracked into these areas by employees' footwear, clothing, or hands. Our review of the instructors' medical monitoring results indicated that BLLs were all below 10 microg/dL of lead. While reviewing medical records, we noted that four instructors had slightly more hearing loss in the left ear than the right ear. Two instructors had threshold shifts that met the NIOSH definition of 15 dB or more at any testing frequency. In addition to our previous recommendation for a new ventilation system, we recommended eliminating dry sweeping, removing carpeting, and improving general housekeeping practices. We also recommended that instructors not use firearms on their workdays and that all personnel working in the firing range wash their hands, arms, and face before eating, drinking, or touching others. Periodic air sampling for lead should be performed whenever changes are made that affect instructor, shooter, or hazardous materials technician exposures. Management should also continue medical monitoring for personnel at the facility.
Region-9; Law-enforcement; Law-enforcement-workers; Lead-compounds; Lead-dust; Indoor-air-pollution; Indoor-environmental-quality; Ventilation; Ventilation-systems; Lead-absorption; Work-practices; Air-sampling; Exposure-assessment; Exposure-levels; Exposure-limits; Air-flow; Sampling; Breathing-zone; Time-weighted-average-exposure; Hazardous-materials; Medical-monitoring; Air-quality-measurement; Worker-health; Workplace-monitoring; Workplace-studies; Hearing-loss; Environmental-control-equipment;
Author Keywords: National Security; lead; CAS# 7439-92-1; Indoor Environmental Quality; IEQ; indoor firing range