CDC Tips on Cleaning HVAC Systems of Flood-Damaged Buildings

During flooding, systems for heating, ventilating, and air conditioning (HVAC) can become submerged in flood waters. As a result, these systems may contain substantial amounts of dirt and debris and may also become contaminated with various types of microorganisms such as bacteria and fungi. The following recommendations will help ensure that HVAC systems contaminated with flood water are properly cleaned and remediated to provide healthy indoor environments.

Microorganisms may grow on all surfaces of HVAC system components that were submerged in flood waters. In addition, moisture can collect in HVAC system components that were not submerged (such as air supply ducts above the water line) and can promote the growth of microorganisms. Therefore, all components of the HVAC system that were contaminated with flood water or moisture should be thoroughly inspected, cleaned of dirt and debris, and disinfected by a qualified professional. The following recommendations will help ensure that HVAC systems contaminated with flood water are properly cleaned and remediated to provide healthy indoor environments.

The CDC has a website “Cleaning Recommendations for the Cleanup and Remediation of Flood-Contaminated HVAC Systems: A Guide for Building Owners and Managers” that covers the following issues:

  • Steps Before Cleaning and Remediation
  • HVAC Cleaning and Remediation
  • Resuming HVAC Operations
  • Additional Resources
  • References