Which controls should be used to reduce exposures below the permissible exposure level?

Engineering controls are the most effective strategy for reducing exposures to hazardous substances below permissible exposure levels. These controls involve modifying equipment or processes to reduce the risk of exposure at the source, which can include methods such as ventilation systems, isolating the hazard, or using machine guards. By addressing the hazard directly, engineering controls help create a safer work environment and prevent exposures before they can occur.

In contrast, while ergonomic controls focus on optimizing the physical environment or processes to enhance worker comfort and reduce the risk of musculoskeletal disorders, they do not specifically address exposure to hazardous substances. Administrative controls involve changes in workplace policies, procedures, or practices to minimize exposure time or increase job rotation, which can be effective but may not reduce exposures as directly or efficiently as engineering controls. Personal protective equipment (PPE) is important for providing a last line of defense for workers, but it does not eliminate the hazard itself; rather, it protects against the consequences of exposure. Therefore, engineering controls should be prioritized as they are aimed at reducing the hazard directly at its source.