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black mold, white mold, green mold, toxic mold

Mold Warning Signs


How Do I Know If I Have a Mold Problem?

To best answer this question we should first define, what a mold “problem” is. Simply stated, a mold problem is mold growing indoors. There is no natural reason for mold to be growing inside buildings where people live and work.


Outdoors, mold is part of the natural environment. Mold grows naturally when organic materials such as foliage, wood, soil, etc., are exposed to moisture. As mold grows, it releases spores into the air. 250,000 mold spores fit on the head of a pin. Even though we cannot see them with the naked eye, spores are always present and the amount of mold spores in the air is usually representative of the amount of mold growth in the same general area. Based on individual sensitivities, humans and animals may experience different reactions in areas where airborne mold spore levels are higher than other areas.

How Does Mold Become An Indoor Problem?

The buildings we live and work in are not airtight. There are many places where air from outdoors comes inside, and air from indoors escapes to outside. To demonstrate this, stand near a window in your house when it is cold outside and you are likely to feel a draft of cooler air from outside coming in. Now consider the size of a mold spore (250,000 on a pinhead). As air from outdoors comes indoors, microscopic organisms, including dust, pollen, and mold spores, are coming in with it. This too is normal and generally not a problem because the air that comes in from outside is also going back outside, which keeps airborne pollutants in equilibrium with outdoors.


The problem begins when those airborne mold spores floating in and out of our buildings find something wet to stick to, or enter an enclosed area where moisture or humidity are trapped. When that happens, spores land on surfaces and within 48 to 72 hours, new mold begins to grow. Once that happens, the new mold growth releases its own spores into the air, which then alters the natural equilibrium of indoor/outdoor spore counts. Eventually, the amount of airborne mold spores indoors exceeds the number of outdoor spores, sometimes significantly, and THAT is a problem. The higher concentration of indoor spores, the greater chance of mold related illnesses.


If Airborne Spores Are Too Small To See, How Do I Know If My Building Has a Problem?

There are two ways to tell if your building has a mold problem. One is to have the building tested. There a number of ways to test a building. The most common and economical way is to collect air samples from indoors and compare them to an air sample from outdoors. Any differences in the types of molds or the volume of spores will indicate whether mold is growing indoors and to what degree. For more information about testing your property, call AMI now at 800.369.8532


Other ways to tell if your home or workplace has a mold problem without scientific testing are:

  1. If you or others notice unusual musty odors when entering the building or a specific room in the building, even if you do not see any mold. Sometimes people blame odors on the age of a building or the age of certain contents like carpet or furniture. But mold has a distinctive odor.

  2. If you see some evidence of possible water damage but you do not see mold. Remember, mold growing indoors is not normal. If mold growth occurs indoors, it is always because something got wet. Often times, even the slightest visible evidence of water damage, stains, unusual textures, etc., are just the tip of an iceberg scenario where there is mold growth inside a wall, ceiling, or floor cavity. If you know of or suspect that there has been any current or past water intrusion events, whether from plumbing leaks, roof leaks, toilet or tub overflows, missing or damaged shower tile, condensation from air conditioners or double-pane windows, slab leaks, sprinklers hitting the building, water pooling up against exterior walls or in a crawls space, there is reason to suspect an indoor mold problem.

  3. If you are experiencing some physical reaction or health condition that you are concerned may be mold related. If you have a mold allergy, your immune system overreacts when you breathe in mold spores. A mold allergy can make you cough, make your eyes itch and cause other symptoms that make you miserable. In some people, mold allergy is linked to asthma and exposure causes restricted breathing and other airway symptoms. If you have a mold allergy, the best defense is to reduce your exposure to the types of mold that cause your reaction. AMI testing services can help identify specific molds in your home or workplace.


Mold allergy symptoms vary from person to person and range from mild to severe. You may have year-round symptoms or symptoms that flare up only during certain times of the year. You may notice symptoms when you are in buildings with high concentrations of mold, and the symptoms decrease of subside when you’re away from that building.

Mold allergy causes the same signs and symptoms that occur in other types of upper respiratory allergies. Signs and symptoms of allergic rhinitis caused by mold allergy can include:

  • Sneezing

  • Runny or stuffy nose

  • Cough and postnasal drip

  • Itchy eyes, nose and throat

  • Watery eyes

  • Dry, scaly skin


Mold Allergy and Asthma

If you have a mold allergy and asthma, your asthma symptoms may be triggered by exposure to mold spores. In some people, exposure to certain molds can cause a severe asthma attack. Signs and symptoms of asthma include:

  • Coughing

  • Wheezing

  • Shortness of breath

  • Chest tightness


When To See a Doctor

If you have a stuffy nose, sneezing, watery eyes, shortness of breath, wheezing or other bothersome symptoms that persist, see your doctor.


The above information is from the Mayo Clinic website. For more information see our page, Health Effects of Mold & Other Airborne Contaminants. AMI is not qualified to diagnose health conditions or make any medical claims whatsoever. However, there are plenty of informational resources concerning mold related health concerns. We advise you to search the web for your particular ailments to see if they might possibly be mold related.

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