Investigation of indoor air quality at the underground shooting range for the training of police officers in Korea

Police officers in Korea undergo regular indoor firearms training, yet exposure to hazardous substances and ventilation effectiveness remain unassessed. This study evaluated air quality and metal concentrations in an underground indoor shooting range equipped with a mechanical ventilation system. Amongst 21 measured elements, lead (Pb) concentrations were from 218.1 to 983.5 µg/m³, with all samples exceeding the occupational exposure limit of 50 µg/m³. The 8-h time-weighted average for Pb exposure, based on a 20-min training session, was 59.3 µg/m³. Real-time measurements confirmed increases in fine particulate matter and carbon monoxide during shooting. Despite adequate ventilation rates, high Pb levels were attributed to ineffective airflow caused by the misplacement of supply and exhaust vents, both located behind the shooters. These findings highlight the urgent need for ventilation system redesign and exposure control in shooting ranges.