What safety measure is required if ambient arsenic levels exceed 10 micrograms per cubic meter?

The requirement for workers to wear approved respirators when ambient arsenic levels exceed 10 micrograms per cubic meter is crucial for ensuring their safety and health. Arsenic is a known hazardous substance that can have serious health effects, including respiratory problems and other long-term health issues.

Approved respirators are designed to filter out harmful airborne contaminants, providing a necessary barrier between the worker and the arsenic present in the environment. This measure minimizes inhalation exposure, which is particularly important given that even low levels of arsenic can be harmful over time.

Adhering to this safety protocol helps to maintain a safe work environment and comply with occupational health and safety regulations, which are designed to protect workers from hazardous substances. The other options do not align with the necessary safety standards required for dealing with arsenic exposure, highlighting the importance of proper respiratory protection for all workers in environments where there are elevated arsenic levels.