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Mold

Mold Remediation in Schools and Commercial Buildings Guide: Chapter 2

Mold Prevention

The content on this web page is based on the publication Mold Remediation in Schools and Commercial Buildings[EPA 402-K-01-001, Reprinted September 2008]. Updates have been made to some resources and links.  

Prevention

The key to mold control is moisture control. Solve moisture problems before they become mold problems!

Mold Prevention Tips

  • Fix leaky plumbing and leaks in the building envelope as soon as possible.

  • Watch for condensation and wet spots. Fix source(s) of moisture problem(s) as soon as possible.

  • Prevent moisture due to condensation by increasing surface temperature or reducing the moisture level in air (humidity). To increase surface temperature, insulate or increase air circulation. To reduce the moisture level in air, repair leaks, increase ventilation (if outside air is cold and dry), or dehumidify (if outdoor air is warm and humid).

  • Keep heating, ventilation and air conditioning (HVAC) drip pans clean, flowing properly and unobstructed.

  • Vent moisture-generating appliances, such as dryers, to the outside where possible.

  • Maintain low indoor humidity, below 60% relative humidity (RH), ideally 30-50%, if possible.

  • Perform regular building/HVAC inspections and maintenance as scheduled.

  • Clean and dry wet or damp spots within 48 hours.

  • Don't let foundations stay wet. Provide drainage and slope the ground away from the foundation.

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