Straight talk about mold and mold spores

You have probably heard about mold and mold exposure in the news. Sometimes this information can cause concern such as reports of “toxic” mold. The purpose of this summary is to give factual information about mold in the environment.

What is mold and what are mold spores?

Molds are living organisms (fungus) found throughout the world. They are especially prevalent along the Gulf Coast. Outdoors, molds play a part in nature by breaking down dead organic matter such as fallen leaves and dead trees, but indoors, mold growth should be avoided. Molds reproduce by means of tiny spores; the spores are invisible to the naked eye and float through outdoor and indoor air. Mold growth indoors, commonly called amplification can occur when mold spores land on surfaces that are wet or moist. This is a totally random process as mold spores lack cognitive abilities. There are many types of mold but none of them will grow without water or moisture.

Can exposure to mold harm me?

Molds have the potential to cause discomfort. Generally, molds produce allergens (substances that can cause allergic reactions). Inhaling or touching mold or mold spores may cause allergic reactions in sensitive individuals however this can vary greatly between individuals. Allergic responses include hay fever-type symptoms, such as sneezing, runny nose, red eyes, and skin rash (dermatitis). These reactions can be immediate or delayed. In addition, mold exposure can irritate the eyes, skin, nose, throat, and lungs of both mold-allergic and non-allergic people. Symptoms other than the allergic and irritant types are not commonly reported due to mold exposure but persons with underlying respiratory conditions such as asthma may experience a greater impact. Research on mold and health effects is ongoing.

Why is moisture level the key in controlling mold growth indoors?

As previously stated, mold spores are constantly drifting through the indoor air. The spores are so small it would take a robust filtration system to eliminate them all from the airstream which can’t be easily done in many buildings. Therefore, most building owners and operators control moisture levels as first defense against mold growth indoors.

While it may seem straightforward to control moisture levels for building operators, this requires close attention to building’s heating, ventilation and air conditioning (HVAC) system along with a constant vigilance to identify and correct any water leaks or spills. Power interruptions and outages can render a HVAC system inactive giving mold spores a chance in higher humidity environments.

Key points for building operators and occupants to remember about mold:

  • When water leaks or spills occur indoors - act quickly. If wet or damp materials or areas are dried 24-48 hours after a leak or spill happens, in most cases mold will not grow.
  • Report mold concerns promptly to the Facility Services Customer Service Center by phone 713-743-4948 or online
  • Keep HVAC system in good operating condition and keep drip pans clean and the drain lines unobstructed and flowing properly.
  • Keep indoor humidity low. If possible, keep indoor humidity below 60 percent (ideally between 30 and 50 percent) relative humidity.

Closing thoughts:

Mold is ubiquitous in the environment. Individuals can experience a wide range of reactions from mold exposure. Most of these reactions are of the allergic type but it can vary greatly per individual. Consult a medical professional if you are having substantial impacts from a suspected mold exposure.

Additional information on mold and mold exposure is readily available from a variety of sources.
Consider the source when accessing mold information. The following sources were accessed by Environmental Health and Safety in the preparation of information: