Case series: from ventilation failure to substitution success in occupational lead poisoning at a Korean indoor firing range

This cluster demonstrates that in environments where hazardous agents are continuously generated, such as indoor firing ranges, engineering controls alone, such as improved ventilation, may not provide adequate protection. Substitution-the most effective intervention within the hierarchy of controls-was essential for eliminating exposure. Furthermore, the toxicokinetics of bone lead in chronically exposed adults highlight the need for ongoing monitoring and cautious decision-making regarding treatment and return-to-work planning.