The Health Hazard Evaluation Program received a request from a management representative at a government agency. The requestor was concerned about potential employee exposures to erionite mineral fibers when employees maintained dirt roads in areas where erionite has been confirmed or is suspected to be present [USGS 1996]. We visited two field offices to assess potential employee exposures to erionite and respirable crystalline silica during road maintenance activities in October 2012 and August 2013. We sent summary letters with preliminary recommendations in October 2012, January 2013, and March 2014.

We took air samples for mineral fibers and respirable crystalline silica on employees who repaired dirt roads and analyzed rock samples. Some employees had silica exposures above occupational exposure limits. We did not find erionite in the air or bulk rock/soil samples. We recommended that the employer not use aggregate that contains erionite to repair roads and that they control dust exposures with ventilated vehicle cabs, wet methods, and other work practices.

Recommended citation for this report: NIOSH [2014]. Health hazard evaluation report: evaluation of erionite and silica exposure during dirt road maintenance. By Beaucham C, Harper M, King B. Cincinnati, OH: U.S. Department of Health and Human Services, Centers for Disease Control and Prevention, National Institute for Occupational Safety and Health, NIOSH HHE Report No. 2012-0141-3220.

Stephen B. Thacker CDC Library collection