It doesn’t matter where in the world you live, chances are that at some stage or another you’re going to find mold in your home. It might be growing on your bathroom walls or on the food in your fridge. It might be black, or green, or white. Or it might change color as it develops and grows.

The question though, when you are dealing with mold in your home, is whether or not it’s a health risk. Or rather, what kind of health risk it is.

Understanding Mold

Mold is a fungal growth that is caused by dampness, often where it is humid, and it occurs naturally. It reproduces from minute spores that float around in the air. You can’t see these with the naked eye, and it is only when the spores come into contact with water – or moisture – that they begin to reproduce.

Outdoors mold plays an important role in nature, breaking down dead leaves and other organic matter. Indoors it MUST be controlled, otherwise it can quickly become a health risk.

Different types of mold produce allergens that cause a range of different reactions including:

  • red eyes,
  • hay fever (runny nose and sneezing),
  • dermatitis (skin rashes),
  • asthma.

Left to develop unstopped, mold can develop into a toxic substance.

You can’t get rid of mold spores indoors, but they won’t develop without the presence of moisture.

Where it forms in persistently damp, humid conditions – like bathrooms and shower rooms – it should be removed. While regular cleaning of these areas after use will usually prevent it from forming, many of us don’t do this, simply because we are constantly bathing and showering on a daily basis – sometimes more than once a day.

Where mold forms because of water problems – for instance where there is a leak of some sort or where the HVAC system is faulty – you need to fix the problem to stop the mold from recurring. This will often require assistance from a professional.

Where it forms on food, whether in the refrigerator or not, that food should be discarded.

Dealing with “Hidden” Mold

Mold is not always immediately visible. For instance it often builds up on the back side (or inside) of wallpaper, paneling, dry walling, or above ceilings and ceiling tiles, and below carpets and carpet tiles or pads. Mold might also form inside walls around pipe work – either due to condensation or leaks – on the surface of walls behind heavy items of furniture, or built-in units, inside ductwork, and in roofing materials. It is common in basements that have a high level of humidity.

Unfortunately where you can’t actually SEE mold beginning to form, it gets pretty bad before you are aware of its existence. Often a nasty moldy smell will be the first indication that mold has formed in your home.

Killing and Cleaning Off Mold

Many mold problems can be tackled by home owners. But as the United States Environmental Protection Agency (the EPA) warns, it is vital to “limit your exposure to mold and mold spores”.

If mold is minimal, you don’t have to wear a full-on health and safety outfit, but if it is extensive, it is worth the effort. Available equipment includes:

  • N-95 respirators that you can buy from hardware stores or from specialist companies that advertise on the Internet.
  • Long rubber gloves – always avoid touching mold with your “bare” hands.
  • Goggles.

You should also wear long pants and a top with long sleeves to prevent direct contact with mold.

Where there has been a major infestation of mold, it’s a good idea to use a biocide – like bleach – that will completely destroy the mold. However the EPA advises against using bleach chlorine products as a routine form of cleaning.

Where biocides and disinfectants are used it is important to ventilate the area thoroughly after use as inhalation of fumes from these products can also be harmful.

Furthermore, killing mold is not enough since “dead” mold often causes an allergic reaction in people who are sensitive. Once the mold has been killed, it MUST be removed completely. This will usually involve scrubbing and wiping, possibly also scraping and flushing with water. But remember to make sure the surfaces are absolutely dry or mold will simply form again.

Mold Prevention and Control

The key to mold prevention is to clean damp or wet areas as quickly as possible (particularly in the case of spillages), and to prevent water from accumulating in or around your house.

For instance you should keep roof gutters clean so that rain water can flow away efficiently. Make sure there is adequate run-off from the house so that water doesn’t collect around or flow into the foundations of the house.

HVAC (heating, ventilation and air conditioning) systems must be kept clean. Check that air conditioning drip pans are clean, and dry them regularly. Make sure that all drain lines flow properly.

When moisture collects on the insides of windows, or on walls and pipes, this is usually a sign of condensation. Dry these surfaces and do whatever is possible to reduce the moisture content of the room. Condensation is often caused by high humidity, and you can help to prevent condensation by increasing air movement in rooms by using fans and/or opening doors and windows. Covering cold surfaces like water pipes with an insulation material also helps.

To reduce humidity:

  • Use de-humidifiers and air conditioners when required.
  • Vent any appliances that produce moisture (clothes driers, kerosene heaters and stoves) to the outside.
  • When you shower, turn on the bathroom fan, or if you don’t have one, open the window.
  • Open windows when you are cooking or using a dish washer.

If you are building a new house, consider using PinkWood building products ( that are factory-treated with a new non-toxic coating that is able to resist both mold and rot fungus.

Testing Mold

In the USA there are no EPA or federal limits for mold or for mold spores. However there are professionals who will take samples of mold to test it. Both the American Industrial Hygiene Association (AIHA) and the American Conference of Governmental Industrial Hygienists (ACGIH) recommend sampling and analytical methods.

Ultimately you are advised to do whatever is necessary when dealing with mold in your home. If it takes professional help, then that’s the way to go.


Please enter your comment!
Please enter your name here