What are regulated areas and how are they established and marked?

Regulated areas are workplace areas where exposures to respirable crystalline silica are, or can reasonably be expected to be, above the PEL. The standard for general industry requires employers to establish, demarcate, and limit access to regulated areas. The employer must also provide respirators and make sure they are used by those who must enter regulated areas.

The purpose of a regulated area is to:

• Ensure that employees know that silica levels are likely to exceed the PEL within the regulated area,
• Restrict the number of employees who could be exposed above the PEL by requiring the employer to mark areas where exposures are or are likely to be higher than the PEL, and
• Make sure that all who enter are properly protected with an appropriate respirator.

Employers must establish regulated areas where exposures to airborne concentrations of respirable crystalline silica are, or can reasonably be expected to be, greater than the PEL. Information used to measure employees’ exposures can be used to determine where regulated areas are required and identify the boundaries of these areas.

For example, employers can use any combination of personal samples (air samples collected near the employee’s breathing zone), or objective data such as exposure mapping and real-time measurements to establish regulated areas.

Employers must demarcate (mark off) regulated areas from the rest of the workplace in a manner that decreases the number of employees exposed to respirable crystalline silica within the regulated area. Cones, stanchions, tape, barricades, lines, or textured flooring are some of the ways of marking the boundaries of regulated areas.

Employers must post a sign at each entrance to regulated areas that reads:

DANGER

RESPIRABLE CRYSTALLINE SILICA

MAY CAUSE CANCER

CAUSES DAMAGE TO LUNGS

WEAR RESPIRATORY PROTECTION IN THIS AREA

AUTHORIZED PERSONNEL ONLY

The signs show employees that they are entering a regulated area, and the sign ensures the employee will know the hazards associated with the area, as well as the need for respiratory protection.