Indoor Air Quality and Indoor Air Pollution

Why is indoor air quality important?

The air quality in public and private buildings is an important factor to your health. Ensuring good air quality in the indoor spaces that you live, work and play can improve your health as well as your quality of life. Many people spend the bulk of their day indoors, so it is important to have healthy indoor air quality and to improve indoor air quality. This is especially true in places where weather conditions prevent people from being outside.

How does indoor air quality affect our health?

Poor indoor air quality can be related to health problems. These can range from mild respiratory issues to more extreme symptoms. Other symptoms that poor air quality can lead to include:

  • eye, nose and sinus irritation
  • headaches
  • fatigue
  • dizziness

Poor indoor air quality influences the risk of respiratory illnesses, allergy and asthma symptoms, and viruses that can be spread through the air. It can also further irritate existing health conditions and worsen symptoms.

What is indoor air pollution?

When many people think of pollution, they think of the air outside. But did you know that air inside can also be polluted? Indoor air pollution is when the indoor air quality is poor. This could be caused by high levels of toxins or chemicals. It could be from poor air flow or ventilation, humidity levels or indoor temperature. The conditions inside and outside of the building affect the air. Construction quality, heating, ventilation and air conditioning (HVAC) systems, and spatial layout can factor into air quality and pollution.

What causes indoor air pollution?

High levels of pollutants, temperature, air flow, and humidity affect air quality. Poor ventilation of indoor spaces can lead to increases in indoor pollution. Ventilation allows air to circulate and dilute pollutants. Poor ventilation may be a result of the absence or poor quality of heat, ventilation and air conditioning (HVAC ) systems.

Young girl sneezing from indoor air pollution. She's near a window but it's closed.

What are the most common indoor air pollutants?

There are many sources of indoor air pollution. Some sources are from items common in many homes. Some examples of air pollutants are:

  • household cleaning products
  • mold
  • tobacco smoke

Fumes also contribute to pollution. Some examples include:

  • oil
  • gas
  • coal
  • wood
  • paint

Gases can contribute to poor indoor air quality, such as:

  • carbon monoxide
  • carbon dioxide
  • nitrogen dioxide
  • ammonia

Deteriorating materials can contribute to indoor air pollution, including:

  • insulation
  • asbestos
  • chemical coatings on furniture

Typically, the higher the concentration of the pollutant and the older the product, the more hazardous it is. Without proper HVAC systems, indoor spaces may let in pesticides, radon and outdoor air pollution.

How do pets contribute to indoor air pollution?

Pets have hair, dander, and saliva (as well as feces and urine). In addition, pests such as mice, dust mites and cockroaches can further cause indoor air problems.

Why is indoor air pollution worse than outdoor air pollution?

If there is little ventilation in an indoor space, pollutants can build up. This can be hazardous and lead to health problems. If there is no outdoor air to dilute the pollutants, it is easier for them to build up to threatening levels. Also, many of us spend the bulk of our days inside, which can increase the exposure to indoor pollutants.

How can indoor air quality be improved?

Indoor air quality can be improved by using air filters in your HVAC systems. Air filters help ensure HVAC systems are functioning at their best levels. The filters trap and block harmful particles from entering your indoor space. If outdoor air quality is poor, recirculation modes can be used. They reduce the intake of outdoor air, preventing outdoor pollutants from entering. Additionally, an air purifier or air cleaner can help clear less serious pollutants.

How can air quality be improved naturally?

You can open doors and windows to provide natural ventilation. You can remove chemicals and hazardous pollutants. Additionally, you can use more natural cleaning materials to improve indoor air quality. Clean your indoor space often by vacuuming or mopping to remove less hazardous pollutants.

How can air quality be tested?

If you suspect you are experiencing symptoms from poor indoor air quality, seek medical care. Your doctor or local health department may have recommendations for testing. You can check your indoor environment for potential sources of air pollutants. Check to make sure your HVAC system is functioning well. Many state and local health departments also offer services to test for serious pollutants.

Do plants help indoor air quality?

There is some debate about how well house plants can remove pollutants from an indoor environment. Houseplants can improve the air quality closely around them. But there is no strong evidence that shows how reliable they are in removing harmful chemicals. Additionally, be careful when choosing what house plants to keep. Some may contain volatile organic compounds, such as bacteria, pesticides or contaminants. Also, avoid over-watering them as it may lead to the growth of microorganisms, such as mold, that may affect allergies.

Photo montage of house graphic, tree, and air pollution contaminant words