Got Mold? Frequently Asked Questions About Mold

The Washington State Department of Health - Office of Environmental Health and Safety provides a webpage that answers many frequently asked questions about mold. Some of these are:

What are molds?

Molds are tiny microscopic organisms that digest organic matter and reproduce by releasing spores. Molds are a type of fungi and there are over 100,000 species. In nature, mold helps decompose or break-down leaves, wood and other plant debris. Molds become a problem when they go where they are not wanted and digest materials such as our homes.

What makes molds grow in my home?

Mold enters your home as tiny spores. The spores need moisture to begin growing, digesting and destroying. Molds can grow on almost any surface, including; wood, ceiling tiles, wallpaper, paints, carpet, sheet rock, and insulation. The mold grows best when there is lots of moisture from a leaky roof, high humidity, or flood. There is no way to get rid of all molds and mold spores from your home. But you can control mold growth by keeping your home dry.

Can I be exposed to mold?

When molds are disturbed, they release spores into the air. You can be exposed by breathing air containing these mold spores. You can also be exposed through touching moldy items, eating moldy food or accidental hand to mouth contact.

Do molds affect my health?

Most molds do not harm healthy people. But people who have allergies or asthma may be more sensitive to molds. Sensitive people may experience skin rash, running nose, eye irritation, cough, nasal congestion, aggravation of asthma or difficulty breathing. People with an immune suppression or underlying lung disease, may be at increased risk for infections from molds. A small number of molds produce toxins called mycotoxins. When people are exposed to high levels of mold mycotoxins they may suffer toxic effects, including fatigue, nausea, headaches, and irritation to the lungs and eyes. If you or your family members have health problems that you suspect are caused by exposure to mold, you should consult with your physician.

When is mold a problem?

You know you have mold when you smell the "musty" odor or see small black or white specks along your damp bathroom or basement walls. Some mold is hidden growing behind wall coverings or ceiling tiles. Even dry, dead mold can cause health problems, so always take precautions when you suspect mold.Mold is often found in areas where water has damaged building materials and furniture from flooding or plumbing leaks. Mold can also be found growing along walls where warm moist air condenses on cooler wall surfaces, such as inside cold exterior walls, behind dressers, headboards, and in closets where articles are stored against walls. Mold often grows in rooms with both high water usage and humidity, such as kitchens, bathrooms, laundry rooms, and basements. If you notice mold or know of water damaged areas in your home, it is time to take action to control its growth

For more answers to common questions about mold go to the Source: http://www.doh.wa.gov/ehp/ts/IAQ/GOT_Mold.html

Conditions That Promote Mold Growth

All of the conditions needed for mold growth (food sources and appropriate temperatures) are present in the indoor environment with the exception of adequate moisture as stated by the N.C. Department of Health and Human Services - Epidemiology Section. Prevention of mold growth indoors can not be achieved without proper moisture control. The following are some of the moisture problems that cause indoor mold growth.

Water Intrusion

Rainwater can enter a building through leaks in walls, windows or the roof. Surface or ground water may enter when there is poor foundation drainage. Flooding can, of course, cause catastrophic intrusion. In buildings that have slab construction, water can seep or wick up through the cement floor causing mold to grow on carpet pads or carpet backing. The building envelope (walls, windows, floors , roof , etc.) must be well maintained to prevent water from coming in, both to prevent mold growth and to maintain the structural integrity of the building.

Water Vapor

When relative humidity (a temperature-dependent measure of water vapor in air) becomes elevated indoors, building materials and furnishings absorb the moisture. Those damp materials can then provide a good place for mold to grow. If there are no cold condensing surfaces and the relative humidity (RH) is maintained below 60 percent indoors, there will not be enough water in those materials for mold to grow. However, if the RH stays above 70 percent indoors for extended periods of time, mold will almost certainly grow.

In the summer, air conditioning can de-humidify indoor space. But if the system is too large or too small for the space it serves, the cooling system can create high humidity by cooling without removing water vapor. A properly sized and maintained system will dehumidify and cool a building.

When there are cold surfaces in a building, water vapor can condense on those surfaces, just as water condenses on the outside of a glass of ice water. Insulation of exterior walls can prevent condensation and mold growth during the winter.

You should always be mindful of indoor sources of water vapor that can be problematic. Clothes dryers must be vented to the outdoors. Unvented gas or kerosene space heaters can generate enormous amounts of water vapor (as well as other air contaminants), and should be used sparingly and never as a primary heat source. Always run the bathroom exhaust fan when showering or bathing, and make sure the vent is exhausted to outdoors. A properly vented kitchen exhaust fan can remove steam created during cooking.

Source: http://www.epi.state.nc.us/epi/oii/mold/conditions.html

Home Moisture Audit Overview

As per Environmental Health Watch - Moisture is both a blessing and a curse. When you have just what you need your health and the health of your buildings is ensured. But when you have too much, your buildings can fail in many ways that can not only damage the structure but affect your health and well-being. The information that follows is a tool to help you keep moisture in your house at acceptable and healthy levels.

The site has good information on moisture issues and problems and provides handy audit sheets. Go to the source for these sheets and more info http://www.ehw.org/Healthy_House/HH_Moist_Audit.htm