Molds and Moisture

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Mold Basics Mold Cleanup Cleanup Guidelines	Hidden Mold Image Library Introduction to Mold	Mold Course Prevention and Control Tips What to Wear When Cleaning Mold	Flood Cleanup Español Indoor Air Quality

Mold cleanup steps

If mold is a problem in your home, clean up the mold and get rid of the excess water or moisture. Fix leaky plumbing or other sources of water. Wash mold off hard surfaces with detergent and water, and dry completely. Absorbent materials (such as ceiling tiles & carpet) that become moldy may have to be replaced. Learn more

Mold growing in a Petri dish

Molds can be found almost anywhere; they can grow on virtually any organic substance, as long as moisture and oxygen are present. There are molds that can grow on wood, paper, carpet, foods, and insulation. When excessive moisture accumulates in buildings or on building materials, mold growth will often occur, particularly if the moisture problem remains undiscovered or unaddressed. It is impossible to eliminate all mold and mold spores in the indoor environment. However, mold growth can be controlled indoors by controlling moisture indoors. Read an Introduction to Mold. | Take our Mold Course

Mold Publications

	"A Brief Guide to Mold, Moisture, and Your Home" HTML \| PDF (20 pp., 1.4 M, about PDF) EPA 402-K-02-003, Reprinted September 2010
	Una Breve Guía para el Moho, la Humedad y su Hogar está disponible en el formato PDF (PDF, 11 pp., 1.28 M) Documento de la agencia EPA número 402-K-03-008, reimprimido el 2010 de mayo
	"Mold Remediation in Schools and Commercial Buildings" HTML \| PDF (56 pp., 1.6 M) EPA 402-K-01-001, Reprinted September 2008

Clinicians Guidance

The "Guidance for Clinicians on the Recognition and Management of Health Effects Related to Mold Exposure and Moisture Indoors" was designed to help the healthcare provider address patients with illnesses related to mold in the indoor environment by providing background understanding of how mold may be affecting patients. The guidance was published in 2004, with support from a grant by the U.S. EPA, by the Center for Indoor Environments and Health, or CIEH at the University of Connecticut Health Center.

Go to the CIEH Website. | Download the "Clinician's Guide on Mold and Moisture PDF" (120 pp., 1.13 M) .

Things You Should Know About Mold

Potential health effects and symptoms associated with mold exposures include allergic reactions, asthma, and other respiratory complaints.
There is no practical way to eliminate all mold and mold spores in the indoor environment; the way to control indoor mold growth is to control moisture.
If mold is a problem in your home or school, you must clean up the mold and eliminate sources of moisture.
Fix the source of the water problem or leak to prevent mold growth.
Reduce indoor humidity (to 30-60%) to decrease mold growth by: venting bathrooms, dryers, and other moisture-generating sources to the outside; using air conditioners and de-humidifiers; increasing ventilation; and using exhaust fans whenever cooking, dishwashing, and cleaning.
Clean and dry any damp or wet building materials and furnishings within 24-48 hours to prevent mold growth.
Clean mold off hard surfaces with water and detergent, and dry completely. Absorbent materials such as ceiling tiles, that are moldy, may need to be replaced.
Prevent condensation: Reduce the potential for condensation on cold surfaces (i.e., windows, piping, exterior walls, roof, or floors) by adding insulation.

Read about more things you need to know about mold

Mold Course

If you are an environmental and/or public health professional, take the Mold Course "Introduction to Mold and Mold Remediation for Environmental and Public Health Professionals." This web-only course contains information on mold prevention and remediation. Learn more Designed primarily for environmental and public health professionals, the Mold Course has nine chapters; these chapters are further divided into smaller lessons. At the end of each chapter there is a voluntary quiz to test your understanding of the material covered. Take a short quiz on your current mold knowledge; begin with the Pre-Test.

The Mold Image Library contains mold-related images in seven categories. These photos may be used for presentations and educational purposes without contacting EPA.

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Publications Glossary of Terms Related Links

EPA's Natural Emergencies El medio ambiente y su salud: Moho

Natural Disasters and Weather Emergencies

Information on Flood Cleanup

EPA's Natural Disasters and Weather Emergencies

Emergency Preparedness at http://www.ready.gov/

Sometimes the power goes out after a flood. Never use a generator inside homes, garages, crawlspaces, sheds, or similar areas. Deadly levels of carbon monoxide can quickly build up in these areas and can linger for hours, even after the generator has shut off.

It is important to dry water damaged areas and items within 24-48 hours to prevent mold growth.

Additional Resources

IAQ Tools for Schools Action Kit - "IAQ Reference Guide - Appendix H: Mold and Moisture".

Indoor Air Quality Building Education and Assessment Model (I-BEAM) Text Modules: Fundamentals of IAQ in Buildings.

"Building Air Quality: A Guide for Building Owners and Facility Managers - Appendix C: Moisture, Mold and Mildew".

WHO Guidelines for Indoor Air Quality: Dampness and Mould (PDF) (248 pp., 2.65 M)

World Health Organization, 2009

EPA's Office of Research and Development Fact Sheet: The Environmental Relative Moldiness Index

Take a Tour of the IAQ House

Get a quick glimpse of some of the most important ways to protect the air in your home. Tour the IAQ House. Room-by-room, you'll learn about and how to address key pollutants. Get an Introduction to Indoor Air Quality.