Fibers per Cubic Centimeter (f/cc)

Fibers per cubic centimeter is a unit that measures how many asbestos fibers are present in a given volume of air. It describes the concentration a person breathes, and combined with how long they were exposed, it estimates the dose received. Workplace safety limits for asbestos are written in these units.

Origin

The measure came into standard use with the air-sampling methods developed in the mid twentieth century, particularly phase-contrast microscopy, which counts fibers collected on a filter. It replaced older, less precise dust measures such as millions of particles per cubic foot.

Significance in Asbestos Context

For patients, f/cc is how experts turn an exposure into a number that can be compared to safety limits and to doses known to cause disease. The current U.S. OSHA permissible exposure limit is 0.1 f/cc averaged over eight hours, but historical workplace levels were often many times higher. Estimating past exposure in f/cc, then multiplying by years of exposure to get fiber-years, helps experts connect a specific job or product to the disease. Defendants often dispute these estimates, so job records and industrial hygiene data that support the concentration figure matter.

Example Sentence

The industrial hygienist estimated that the dust near the saw exposed my husband to several fibers per cubic centimeter, far above today's legal limit.

Related Terms

Fiber-Years, Permissible Exposure Limit, Dose-Response, Cumulative Exposure, Phase-Contrast Microscopy, Threshold Limit Value

Notes

• Ask whether an industrial hygienist can reconstruct your exposure in f/cc using your job history and known product data.
• Preserve any old air-monitoring records, union safety data, or plant industrial hygiene reports.
• Note that f/cc counts fibers by microscopy but doesn't identify the fiber type; pairing it with fiber analysis strengthens the picture.