Indoor air pollution refers to the presence of harmful contaminants inside your home — particles, gases, and biological agents that reduce air quality and can affect your health. The EPA has long noted that indoor air is often significantly more polluted than outdoor air, even in cities, because homes trap and concentrate contaminants without the natural dilution that occurs outside. In Colorado, where homes are tightly sealed for much of the year to handle wide temperature swings, indoor air pollution is a concern that affects virtually every household.

The Main Categories of Indoor Air Pollutants

Indoor air pollution isn’t one thing — it’s a category that includes several distinct types of contaminants:

  • Particulate matter — Dust, pet dander, pollen, mold spores, and fine particles from cooking or candles. These are the most common irritants and can aggravate asthma and allergies.
  • Volatile organic compounds (VOCs) — Gases released from paints, adhesives, cleaning products, new furniture, and building materials. Formaldehyde is one of the most common.
  • Combustion byproducts — Carbon monoxide and nitrogen dioxide from gas appliances, fireplaces, attached garages, or tobacco smoke. CO is odorless and potentially fatal.
  • Biological contaminants — Mold, bacteria, viruses, and dust mites that thrive in humid or poorly ventilated areas.
  • Radon — A naturally occurring radioactive gas that seeps from soil and rock. Colorado has areas with elevated radon levels, and it’s the second leading cause of lung cancer in the U.S.

Why Colorado Homes Face Specific Challenges

Denver and the Front Range present a particular set of indoor air quality challenges. Our dry, low-humidity climate means dust circulates freely and static electricity keeps fine particles airborne longer. At 5,280 feet and above, there’s less atmospheric filtering of UV radiation, and wildfire smoke — increasingly common during Colorado summers — sends fine particulate matter (PM2.5) pouring into homes through every gap and HVAC intake.

Colorado also has a significant radon risk. The geology of the Rocky Mountain region contributes to higher-than-average radon concentrations in many Front Range basements and crawlspaces. If your home has never been tested, it’s worth doing — radon test kits are widely available, and mitigation systems are straightforward to install.

The expansive clay soils along the Front Range also affect home foundations over time, and any resulting cracks in basement floors or walls can increase radon entry and moisture infiltration that leads to mold.

Health Effects of Indoor Air Pollution

Short-term exposure to indoor pollutants can cause headaches, fatigue, eye and throat irritation, dizziness, and worsened allergy or asthma symptoms. Long-term exposure to certain contaminants — particularly VOCs, radon, and fine particulate matter — is associated with more serious respiratory and cardiovascular conditions. Children, the elderly, and people with existing respiratory conditions are generally more sensitive to indoor air quality problems.

Carbon monoxide deserves special mention: it’s colorless and odorless, and at high concentrations it can be rapidly incapacitating. Every Colorado home with a gas furnace, water heater, fireplace, or attached garage should have working CO detectors on every level.

What You Can Do About It

Improving indoor air quality is a multi-pronged effort. Upgrading your HVAC filter to a higher MERV rating captures more fine particles. Whole-home air purifiers and UV germicidal lights address biological contaminants. Proper ventilation — whether through an energy recovery ventilator (ERV) or strategic window use — dilutes accumulated pollutants. Keeping your ductwork clean removes a major reservoir of dust and debris that gets recirculated every time your system runs.

Done offers a full range of indoor air quality services for Denver-area homeowners, including air purifiers, filtration upgrades, humidity control, and ventilation solutions. If your ducts haven’t been cleaned in several years, duct cleaning can meaningfully reduce the particulate load in your home. And if your HVAC system is aging, a properly maintained or replaced system on our AC maintenance or furnace maintenance plan will filter and condition your air far more effectively. Contact Done to discuss what your home needs.