Valley Fever, Prevention in a work setting

Bulldozing Back Dirt

Prevention in a work setting

NIOSH recommendations in workplace health hazard evaluations have paralleled those of the California Department of Public Health (CDPH)external icon, who have produced a useful fact sheet that provides comprehensive recommendations for minimizing dust exposure and risk of coccidioidomycosis for those working in endemic areas.

Recommended controls include:

  • Stop work in dust storms or high winds
  • Minimize hand digging; digging with heavy equipment having enclosed, air-conditioned, HEPA-filtered cabs is recommended
  • Continuously wet soil while digging or moving earth
  • Stay upwind of digging, when possible

It is important that workers understand the potential hazards related to their work and how to protect themselves. OSHA’s Hazard Communication Standard, also known as the Right to Know Law – 29 CFR 1910.1200external icon requires that employees are informed and trained of potential work hazards and associated safe practices, procedures, and protective measures.

CDPH recommends that workers and supervisors be provided training on the following:

  • Endemic areas
  • Symptoms and when to report them
  • Those at highest risk of serious disease
  • Effective controls

Respiratory protection is recommended for those who:

  • Dig manually
  • Dig using equipment (including enclosed heavy equipment)
  • Work near earth-moving trucks or equipment in endemic areas

Respirators for employees should be certified by NIOSH and provided within the context of a comprehensive respiratory protection program, which includes:

  • Medical clearance for use of respirators
  • Initial and periodic training and fit testing
  • Monitoring the effectiveness of the respirators

The Occupational Safety and Health Administration respiratory protection standard describes the components of a comprehensive respiratory protection program (29 CFR 1910.134external icon). Because as little as one spore may transmit disease, when potential exposure to dust is unavoidable, the employer should assess the associated risk and determine the level of respiratory protection needed based on the effectiveness of the various types of respirators for particles of dusts and spores. Respirator information can be found on the NIOSH website at CDPH1and Das et al.2 note that a fit tested half-mask respirator with particulate filter or a filtering facepiece respirator might be insufficient to protect the worker. Some workers, such as those with beards, cannot wear tight-fitting respirators. Loose-fitting powered air-purifying respirators are an option in that situation.

It is recommended that employers:

  • Wash equipment before it is moved offsite
  • Provide lockers and require that workers change clothing and shoes at the worksite so they don’t take dust and spores home
  • Arrange for prompt medical evaluation and treatment of those with possible disease


  1. California Department of Public Health (CDPH) [2013]. Preventing work-related coccidioidomycosis (Valley Fever) [ iconexternal icon]. Date accessed: October 6, 2014
  2. Das R, McNary J, Fitzsimmons K, Dobraca D, Cummings K, Mohle-Boetani J, Wheeler C, McDowell A, Iossifova Y, Bailey R, Kreiss K, Materna B [2012]. Occupational coccidioidomycosis in California: outbreak investigation, respirator recommendations, and surveillance findings. J Occup Environ Med. 2012 May;54(5):564-71. doi: 10.1097/JOM.0b013e3182480556. PubMed PMID: 22504958.
Page last reviewed: November 19, 2018