Indoor air quality is measured by testing the concentration of specific pollutants and tracking physical conditions like humidity and ventilation rates. Professionals use calibrated instruments to detect particulate matter, volatile organic compounds (VOCs), carbon monoxide, carbon dioxide, radon, and biological contaminants like mold spores. A baseline IAQ assessment gives homeowners a factual picture of what’s in the air they breathe every day — and what, if anything, needs to be done about it.

The Key Things Being Measured

A thorough indoor air quality evaluation covers several categories of contaminants and conditions:

  • Particulate matter (PM2.5 and PM10): Fine particles from dust, pet dander, pollen, and wildfire smoke. Denver and the Front Range have seasonal wildfire smoke events that can dramatically spike indoor particulate levels even with windows closed.
  • Carbon monoxide (CO): An odorless gas produced by gas furnaces, water heaters, and attached garages. CO is dangerous at elevated levels — testing is especially important in Colorado homes because altitude affects combustion efficiency in gas appliances.
  • Carbon dioxide (CO2): A proxy for ventilation adequacy. High CO2 indicates stale, under-ventilated air — common in well-sealed modern homes built for energy efficiency.
  • Volatile organic compounds (VOCs): Off-gassing from paints, adhesives, flooring, cleaning products, and furniture. Newer homes or recently renovated spaces often have elevated VOC levels.
  • Radon: Colorado has one of the highest radon concentrations in the country. This naturally occurring gas seeps up from the soil and accumulates in basements and lower levels. The EPA recommends testing every home.
  • Relative humidity: Colorado’s air is very dry — typically 20–40% relative humidity — which can irritate airways, dry out wood, and increase static electricity. Very low humidity also allows viruses to spread more easily.

Professional Monitoring vs. Consumer Devices

Consumer air quality monitors (devices that sit on a countertop and give you a number) can track basic metrics like PM2.5, CO2, temperature, and humidity. They’re useful for spotting trends — a spike when you run the oven, or elevated particulates during a wildfire event — but they aren’t calibrated instruments. For a legally or medically meaningful result, or to diagnose a specific problem like mold or elevated radon, you need professional-grade equipment and someone trained to interpret the readings in context.

What Affects Indoor Air Quality in Colorado Homes

At 5,280 feet and above, Denver homes face a specific set of IAQ challenges. The dry climate means that dust and fine particles stay suspended in the air longer rather than settling. Tight energy-efficient building envelopes reduce fresh air exchange, concentrating indoor pollutants. Gas appliances operating at altitude run with less oxygen, which can affect combustion completeness. And wildfire smoke season — increasingly common across the Front Range — introduces fine particulates that penetrate standard fiberglass filters with ease.

What Happens After a Measurement

The value of measuring IAQ is in knowing what to fix. High particulates might call for a higher-efficiency air filter or a whole-home air purifier. Low humidity points to a whole-house humidifier. CO concerns require a combustion analysis of your gas appliances. Elevated radon needs a mitigation system. An IAQ professional can connect the data to specific solutions rather than guessing.

How Done Approaches Indoor Air Quality

Done’s indoor air quality services start with understanding what’s actually happening in your home before recommending equipment. That approach means solutions are targeted, not generic. Whether the concern is wildfire smoke, dry winter air, or something less visible like VOCs, the team can test, advise, and install the right equipment to address it.

Ready to find out what’s in your home’s air? Start with Done’s indoor air quality services. If ductwork is part of the equation, duct cleaning and duct services can make a meaningful difference in what your system circulates.