Myth-busting Mold

By Lt. Cmdr. Genaia Hill, industrial hygienist, Beaufort Naval Hospital, S.C.   

Like asbestos or lead, mold in buildings is getting a lot of attention as a potential health hazard. As an industrial hygienist, I hope to provide people with basic information about mold so they are better able to manage it and are less fearful about this common environmental agent that is similar to dust and pollen in the air at work and at home.

So what exactly is mold? Molds are forms of fungi that are found naturally in the environment. Tiny particles of molds are found everywhere in indoor and outdoor air and come in a variety of colors and textures. Molds are an important part of the ecosystem that help breakdown dead material and recycle nutrients in the environment. In order to reproduce, molds produce spores, which spread through air and water. These spores act like seeds and can form new mold growth if the conditions are right.  Essentially, mold growth is an indication of a moisture problem, and it does not always pose a health hazard.

Where does mold grow?  Molds grow best in warm, damp, and humid conditions. Outdoors they can be found in shady, damp areas or places where leaves or other vegetation is decomposing. Indoors, mold will grow in places with a lot of moisture, such as around leaks in roofs, windows, or pipes, or where there has been flooding. Mold grows well on paper products like cardboard, ceiling tiles, and wood products. Mold can also grow on dust, wallpaper, insulation, drywall, carpet, fabric, and upholstery.   

Moisture problems in buildings can be related to air condition condensation, poor HVAC performance, insufficient building insulation, leaking pipes, roofs or windows, and ventilation fans not exhausting moisture from showers. Climate conditions such as excessive humidity and rain can also contribute to excess moisture resulting in mold growth.

People can contribute to mold growth too. Building occupants can contribute to moisture problems by opening windows during HVAC seasons, not performing periodic housekeeping, not using ventilation fans, and setting HVAC systems to extremely low temperatures causing condensation to form on windows and walls. All of these actions can create moisture in the environment, which may lead to mold growth.

Can mold cause health problems?  For individuals who are sensitive, exposure to mold can cause symptoms such as a runny nose, scratchy throat, itchy eyes, sneezing, and in more severe cases, wheezing and coughing. Anyone who believes they may be experiencing health effects due to exposure to mold should see their doctor. 

Can you sample for mold?  Often, industrial hygienists are called upon to sample for mold.  In cases of mold presence in buildings or homes, sampling to determine the species of mold is unnecessary and is not recommended by the Centers for Disease Control and Prevention.  There is very limited information about what levels of mold exposure are associated with health effects and no federal standards exist to regulate it.

What do you do if mold is growing indoors?  Identifying and correcting the source of moisture will eliminate and prevent future mold growth.  Depending on the size of the problem and the materials with mold growth, cleaning small hard surfaces with detergent and water can handle the problem.  Large scale mold problems from flooding or water pipe breaks could require more involved cleaning operations and guidance should be sought from reputable sources such as Facilities, Safety Offices or Industrial Hygiene on your local military installation.

What are some tips to prevent mold growth?  That depends on where the mold problem is and your ability to control factors that contribute to its growth. At home, use exhaust fans in the bathroom when showering, clean all spills on soft surfaces like rugs and upholstered furniture thoroughly and immediately, do not run the your air conditioner and open windows simultaneously, open curtains and blinds to let in natural sunlight which inhibits mold growth and make sure your clothes dryer vents outside your home. 

At work, many of the factors that control mold growth are handled by the facilities manager which includes controlling humidity levels, adequate airflow, setting temperatures at reasonable levels and making facility repairs that contribute to excess moisture like a leaking roof or pipe.  However, being pro-active at home and work can help reduce the spread of mold by performing routine inspections of ceilings, windows, walls and floors and looking for rust, water and mold. It is always important to perform routine housekeeping in all areas to prevent sources of mold growth. Early detection and prompt intervention will eliminate mold growth and spread where ever it is found.

There is a lot of information about the dangers of mold in the media and mold remediation is big business! In order to obtain balanced information, always seek information from a reliable source such as the Centers for Disease Control and Prevention and other well-respected agencies. On military installations, Public Works or Facilities Management Departments, Safety Offices and Industrial Hygiene can also provide assistance and guidance.