A BRIEF GUIDE TO

MOLD, MOISTURE,

AND

YOUR HOME

EPA 402-K-02-003

This Guide provides information and guidance

for homeowners and renters on how to clean

up residential mold problems and how to

prevent mold growth.

U.S. Environmental Protection Agency Office of Air and Radiation Indoor Environments Division 1200 Pennsylvania Avenue Mailcode: 6609J Washington, DC 20460 www.epa.gov/iaq

A BRIEF GUIDE TO MOLD, MOISTURE, AND YOUR HOME

Contents Page Mold Basics

  • Mold Basics
  • Why is mold growing in my home?
  • Can mold cause health problems?
  • How do I get rid of mold?

2 2 3

  • How do I get rid of mold? 3 Mold Cleanup

  • Mold Cleanup

  • Who should do the cleanup?

  • Mold Cleanup Guidelines

  • What to Wear When Cleaning Moldy Areas

  • How Do I Know When the Remediation or Cleanup is Finished?

  • Moisture and Mold Prevention and Control Tips

  • Actions that will help to reduce humidity

  • Actions that will help prevent condensation

  • Testing or sampling for mold

4 6 8 9 10 11 12 13

Cleanup and Biocides 15 Additional Resources 16

MOLD BASICS

  • The key to mold control is moisture control.
  • If mold is a problem in your home, you should clean up the mold promptly and fix the water problem.
  • It is important to dry water-damaged areas and items within 24-48 hours to prevent mold growth.

Can mold cause health problems?

Molds are usually not a problem indoors, unless mold spores land on a wet or damp spot and begin growing. Molds have the potential to cause health problems. Molds produce allergens (substances that can cause allergic reactions), irritants, and in some cases, potentially toxic substances (mycotoxins).

Inhaling or touching mold or mold spores may cause allergic reactions in sensitive individuals. Allergic responses include hay fever-type symptoms, such as sneezing, runny nose, red eyes, and skin rash (dermatitis).

How do I get rid of mold?

It is impossible to get rid of all mold and mold spores indoors; some mold spores will be found floating through the air and in house dust. The mold spores will not grow if moisture is not present. Indoor mold growth can and should be prevented or controlled by controlling moisture indoors. If there is mold growth in your home, you must clean up the mold and fix the water problem. If you clean up the mold, but don’t fix the water problem, then, most likely, the mold problem will come back.

If you already have a mold problem – ACT QUICKLY.

  • If there has been a lot of water damage, and/or mold growth covers more than 10 square feet, consult the U.S. Environmental Protection Agency (EPA) guide: Mold Remediation in Schools and Commercial Buildings.
  • If you choose to hire a contractor (or other professional service provider) to do the cleanup, make sure the contractor has experience cleaning up mold. Check references and ask the contractor to follow the recommendations in EPA’s Mold Remediation in Schools and Commercial Buildings.
  • If you suspect that the HVAC system may be contaminated with mold, consult EPA’s guide.
  • If the water and/or mold damage was caused by sewage or other contaminated water, then call in a professional.
  • If you have health concerns, consult a health professional before starting cleanup.

MOLD CLEANUP GUIDELINES

Bathroom Tip

Places that are often or always damp can be hard to maintain completely free of mold. If there’s some mold in the shower or elsewhere in the bathroom that seems to reappear, increasing the ventilation and cleaning more frequently will usually prevent mold from recurring.

Tips and techniques

  • Fix plumbing leaks and other water problems as soon as possible. Dry all items completely.
  • Scrub mold off hard surfaces with detergent and water, and dry completely.
  • Absorbent or porous materials may have to be thrown away if they become moldy.
  • Avoid exposing yourself or others to mold.
  • If you are unsure about how to clean an item, or if the item is expensive or of sentimental value, you may wish to consult a specialist.
  • Do not paint or caulk moldy surfaces. Clean up the mold and dry the surfaces before painting.

WHAT TO WEAR WHEN CLEANING MOLDY AREAS

It is important to take precautions to LIMIT YOUR EXPOSURE.

  • Avoid breathing in mold or mold spores.
  • Wear gloves. Long gloves are recommended.
  • Wear goggles that do not have ventilation holes.

How do I know when the remediation or cleanup is finished?

You must have completely fixed the water or moisture problem before the cleanup can be considered finished.

  • Ultimately, this is a judgment call; if you have concerns call the EPA Indoor Air Quality Information Clearinghouse.

MOISTURE AND MOLD PREVENTION AND CONTROL TIPS

  • When water leaks or spills occur indoors - ACT QUICKLY.
  • Clean and repair roof gutters regularly.
  • Keep indoor humidity low.
  • If you see condensation or moisture collecting on windows, walls or pipes - ACT QUICKLY to dry the wet surface and reduce the moisture/water source.

Actions that will help to reduce humidity:

  • Vent appliances that produce moisture to the outside where possible.
  • Use air conditioners and/or de-humidifiers when needed.
  • Run the bathroom fan or open the window when showering.

Actions that will help prevent condensation:

  • Increase ventilation or air movement.
  • Cover cold surfaces, such as cold water pipes, with insulation.
  • Increase air temperature.

Renters: Report all plumbing leaks and moisture problems immediately to your building owner.

Testing or sampling for mold

In most cases, if visible mold growth is present, sampling is unnecessary.

HIDDEN MOLD

You may suspect hidden mold if a building smells moldy or if you know there has been water damage and residents are reporting health problems.

Investigating hidden mold problems

Investigating hidden mold problems may be difficult and may require caution.

Cleanup and Biocides

The use of a chemical or biocide that kills organisms such as mold is not recommended as a routine practice during mold cleanup.

Please note: Dead mold may still cause allergic reactions in some people.

Water stain on a basement wall — locate and fix the source of the water promptly.

ADDITIONAL RESOURCES

For more information on mold-related issues, you can call the EPA Indoor Air Quality Information Clearinghouse at

(800) 438-4318.

Or visit:

www.epa.gov/mold

NOTES

Acknowledgements

EPA would like to thank Paul Ellringer, PE, CIH, for providing the photo on page 14.

Please note that this document presents recommendations. EPA does not regulate mold or mold spores in indoor air.

EPA