Integrative Medicine · Indoor air and your body

Brain, heart and lungs

How the air at home reaches all three

Most people spend about 90 percent of their time indoors, according to the EPA. Every breath of indoor air meets your lungs first, and some of what gets past them can travel in your blood. Here is what is known, in plain English, and what you can do at home.

Facts from the EPA and CDCPlain EnglishNothing is sold
How it travels

From the air in the room to the rest of your body

Your body has good defenses, but they are not perfect. This is the path that indoor air follows.

1

Indoor air

Home, work and school. It can carry particles, gases, moisture-related contaminants and smoke.

2

Lungs

First contact. Your nose and airways catch much of what you breathe, but not all of it.

3

Heart and blood

The EPA says the smallest particles can get deep into the lungs, and some may get into the bloodstream.

4

Brain

Your brain depends on a steady supply of oxygen from your blood. Some gases, like carbon monoxide, interfere with that.

01 · Lungs

Where the air first meets the body

What the science says

  • The EPA links particle pollution to worse asthma, lower lung function, coughing and trouble breathing.
  • The CDC says mold can cause coughing or wheezing in some people, and people with asthma may have severe reactions.
  • The EPA calls radon, an invisible gas from the ground, the number one cause of lung cancer among nonsmokers and the second leading cause overall.

Common indoor sources

SmokeMold and dampnessRadonDustGas appliances
02 · Heart

The heart carries what the lungs let through

What the science says

  • The EPA links particle pollution to nonfatal heart attacks and irregular heartbeat.
  • The EPA also links it to early death in people who already have heart or lung disease.
  • The EPA says even low levels of carbon monoxide can cause chest pain in people with heart disease.

Common indoor sources

Wildfire and tobacco smokeCooking and gas stovesCar exhaust from an attached garage
03 · Brain

The brain depends on a steady supply of oxygen

What the science says

  • The EPA says carbon monoxide can cause headaches, dizziness, confusion and trouble with vision and coordination. At very high levels, it can kill.
  • The EPA notes that some indoor pollutants cause effects soon after exposure, while others show up years later.
  • Researchers are also studying how long-term air pollution may affect memory and thinking. That science is still developing.

Common indoor sources

Fuel-burning heaters and furnacesGeneratorsAttached garagesPoor ventilation
Who may be more affected

Some people feel it first

The EPA says these groups are most likely to be affected by particle pollution:

  • People with heart or lung disease
  • Children
  • Older adults

If you or someone at home is in one of these groups, or is already sensitive to indoor environments, talk with your healthcare provider. Only a licensed provider can say what your building means for your health.

What actually helps

Five steps for cleaner indoor air

These steps help all three organs at once, because they all share the same air.

Control the source

The EPA says this is usually the most effective step. Fix leaks, keep fuel-burning appliances serviced, and do not smoke or idle a car in an attached garage.

Bring in fresh air

Use kitchen and bath exhaust fans. The EPA says when too little outdoor air comes in, pollutants can build up.

Filter what is left

Air cleaners and good furnace filters can catch particles. They help, but they do not fix the source.

Install CO alarms

Put carbon monoxide alarms near sleeping areas and on every level of the home. Test them often.

Test for radon

Radon has no smell or color. The U.S. Surgeon General has urged Americans to test their homes.

“Environmental health is the missing piece of the holistic wellness pie.”

The HBIA position

Where HBIA fits

Your provider handles your health. We help with the building.

HBIA works alongside healthcare providers, not in place of them. Read more on our Integrative Medicine page.

What HBIA offers

  • Free, plain-English guides for your home
  • Standards for the work that others do in buildings
  • Help knowing what to ask before you hire anyone

What HBIA does not do

  • Diagnose, treat or interpret health conditions
  • Perform mold removal or construction
  • Take referral fees

Have a question about the air at home?

Tell us what is happening. We will point you to the right guide, or tell you honestly if you need more than a guide.

Prefer to talk to someone? 1-800-781-7986

Training and certification. HBIA has certified indoor environmental professionals under its earlier program since 2005, and certifications issued under that program remain valid. The current HBIA certification program — a revised standard with an expanded review process — is in development. Until it launches, completing an HBIA training course results in a Letter of Course Completion, which confirms training only and is not a certification under the new program. Under that program as designed, a review board will evaluate the letter alongside verified credentials; completing a course will not guarantee certification.

What HBIA certification is and is not. HBIA certifies individuals and firms against its own published standards. HBIA is not a licensing authority and does not issue or replace any state license. Where a credential requires a professional license, HBIA verifies a license issued by someone else — it does not grant one. HBIA is not a 501(c)(3), and is not accredited by ANSI, ANAB, or NCCA.

Ownership disclosure. The Healthy Building Institute of America was incorporated in Ohio in 2005 and is currently a division of WeSpiritus, LLC. HBIA shares common ownership with AMOLDBUSTER and Apollo Environmental Solutions, which provide independent indoor environmental assessment and consultation services and perform no remediation. HBIA does not receive referral fees, and HBIA training and certification do not require the use of any affiliated company, product, or brand. HBIA is working toward establishing the institute as a separate legal entity.

Scope. HBIA characterizes indoor environments and sets standards for work performed by others. HBIA does not perform remediation or construction. HBIA is not a medical provider and does not diagnose, treat, or interpret health status. All health decisions remain with licensed healthcare professionals.

Educational content only. Information provided by HBIA is educational and does not constitute medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified healthcare provider with any questions regarding a medical condition.

Page reviewed and updated October 13, 2026.

© 2026 Healthy Building Institute of America (HBIA). All rights reserved. Education today for healthier buildings tomorrow.
Educational Content Only. The information on hbiatoday.com is provided for educational and informational purposes and does not constitute medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified healthcare provider with any questions regarding a medical condition. The Healthy Building Institute of America certifies indoor environmental professionals; we do not provide medical care.