What is the asbestos PEL and excursion limit?

• A. 0.1 f/cc 8 hr TWA; 1.0 f/cc over 30 minutes
• B. 0.02 f/cc 8 hr TWA; 0.2 f/cc over 15 minutes
• C. 0.2 f/cc 8 hr TWA; 2.0 f/cc over 60 minutes
• D. 0.01 f/cc 8 hr TWA; 0.1 f/cc over 30 minutes

Answer: (A)

Asbestos exposure limits are defined by a long-term limit (an 8-hour time-weighted average) and a short-term limit (an excursion over a 30-minute period). The regulatory standard sets the long-term permissible exposure limit at 0.1 fibers per cubic centimeter (f/cc) averaged over 8 hours, and the short-term excursion limit at 1.0 f/cc for any 30-minute period. This combination protects workers from the health risks of prolonged exposure while also preventing dangerous spikes that can occur during brief, intense tasks.

The correct option matches these values exactly: 0.1 f/cc as an 8-hour TWA and 1.0 f/cc over 30 minutes. The other options propose different numbers that do not align with the OSHA asbestos standard, so they aren’t correct.