What Are the 4 Major Indoor Air Pollutants

indoor air pollutants to watch for
Pollutants in the air in your home can cause health problems, make the home less comfortable and cost you money repairing your air systems. Indoor air quality problems are the most common air quality issues in the United States according to the Environmental Protection Agency and are more disruptive because it is concentrated and constant. Common indoor air pollutants include excessive moisture, radon, combustion products, volatile organic compounds and tobacco smoke. All of these come from different causes and are destructive in their own way, but many can be prevented or treated. Learn about the four major indoor air pollutants below.

Moisture Based Air Pollutants

Moisture is one of the main elements you want to control in your home. It is one of the most important and least recognized indoor pollutants, as it affects both the health of the building and the health of the people inside. Moisture can collect wherever warm air meets cool surfaces, such as bathrooms, window ledges or walls in cooler spaces. Cool air holds less moisture, so moisture condenses on surfaces in droplet form, instead of being held in the air. In addition, moisture can gather through leaks, floods, plants, unvented appliances or even through ground condensation in wood or concrete flooring. If moisture is mitigated, such as by use of a fan or regular cleaning, it is not an issue. However, if excessive moisture gathers in places, it can lead to pollutants such as:

  • Mold
  • Mildew
  • Dust Mites

In addition, these pollutants can cause more serious problems for you and your home, including:

  • Asthma
  • Allergies
  • Accelerate rust on metal building
  • Accelerate decomposition in wood spaces

And while all of those are reason enough to avoid excessive moisture in your home, you can also create an uncomfortable environment, either by a home being too humid or having a cold-clammy feeling inside.

Solving the Moisture Air Pollutants

The key to fighting mold, mildew and dust is to keep moisture and humidity levels in check. Fix any plumbing leaks, be aware of potential flooding hazards and ensure your HVAC system is maintained annually to keep humidity level normal in your home. If you discover mold or mildew, clean the area and find the source of the growth immediately.


Radon is a radioactive gas that is the second leading cause of lung cancer in the United States. It is generated naturally in soil, and enters the home through the ground, although the concentration level can vary from place to place. However, the good news is that there are simple and effective systems that easily vent the radon away from your residential home or building.

Removing the Source of Radon

If you are concerned about radon in your home, you can screen your home for radon. Radon screening kits can be purchased online and at some home improvement stores; there are also professional services that can test your radon levels in your home and help mitigate any issues.

Combustion Products

Many of the appliances in your home release gases into the air. Appliances to watch out for include:

  • Furnaces
  • Water Heaters
  • Ranges
  • Dryers

These appliances, while built to properly vent to the outside, can sometimes malfunction or be set up improperly. Exhaust from cars and trucks can also be a source of combustion products, if a garage nearby is not vented properly. If these are not venting properly or if the air pressures around the appliance is negative enough to cause backdrafting, combustion pollutants can enter the home. These could include:

  • Carbon Dioxide
  • Carbon Monoxide
  • Nitrous Oxides
  • Water Vapor

Carbon monoxide can be particularly dangerous, because it is colorless and odorless that is difficult to detect. This toxic gas can be fatal, as it stops the body from using oxygen it needs to work normally. Symptoms of carbon monoxide poisoning include headaches, dizziness, nausea, confusion and increased heart rate; if you suspect you may have been exposed to carbon monoxide poisoning, leave your home and call emergency services immediately.

Fixing Combustion Products

We recommend having your heating and cooling system checked annually by an HVAC professional to ensure it is propertly removing pollutants and gases. In addition, make usre appliances are installed and maintained by professionals and utilize a carbon monoxide detector in your home.

Volatile Organic Compounds (VOC)

VOCs include a variety of evaporated substances that can be emitted by building material and furnishings, including:

  • Furniture
  • Carpets
  • Gasoline
  • Pesticides

While many of these are simply a nuisance (think body odors or the pungent smell of frying onions), some, like formaldehyde, can be a threat to health.

Bonus: Tobacco smoke

Smoking and tobacco smoke is notable because of its health consequences, even for non-smokers. Smoking and tobacco use produces copious amounts of harmful gases and chemicals, which greatly deteriorate indoor air quality and put the health of those inside at risk.

If you’re concerned about the air quality or pollutants in your home, you should contact your HVAC professional for annual maintenance on your HVAC system. Companies such as Central Heating, Cooling, Plumbing and Electrical can help check for issues with your system and provide solutions that will save you time and money, as well as protect your health. Contact us today to schedule your appointment.

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