Radon and Indoor Air Quality: What's Actually Worth Testing For

Indoor air quality concerns range from genuinely serious and easy to test for, to marketing-driven concerns with little practical benefit from a home detector. Radon and carbon monoxide sit firmly in the first category.

Radon: test regardless of your area's general risk level

Radon is a naturally occurring radioactive gas that seeps up from soil and rock and can accumulate in enclosed spaces, particularly basements. It's odorless and invisible, and long-term exposure at elevated levels is a well-established lung cancer risk, second only to smoking. Regional radon risk maps are useful for context but not a substitute for testing — levels vary significantly even between neighboring homes depending on foundation type and local geology.

Radon mitigation, if needed

The standard fix is a sub-slab depressurization system: a pipe and fan that draw radon-laden air from beneath the foundation and vent it above the roofline before it enters the living space. This is a licensed-contractor job in most cases — it requires understanding the specific foundation type and often permitting, and a poorly installed system can be ineffective or even depressurize the house in unintended ways.

Carbon monoxide: a life-safety issue, not an air-quality nuance

CO is produced by incomplete combustion in fuel-burning appliances — furnaces, water heaters, gas stoves, fireplaces, and attached garages. Unlike radon, CO exposure can be acutely dangerous within hours, not just over years. Every home with any fuel-burning appliance or an attached garage should have working CO detectors near sleeping areas, tested regularly, with batteries replaced on schedule.

• Install CO detectors outside each sleeping area and on every level of the home.
• Have fuel-burning appliances and chimneys/flues inspected annually by a qualified technician.
• Never run a generator, grill, or any gas engine inside a garage, even with the door open.
• If a CO alarm sounds, get everyone outside into fresh air immediately and call emergency services before troubleshooting the source.

VOCs, particulates, and general 'indoor air quality' monitors

Consumer air quality monitors that track VOCs (volatile organic compounds) and fine particulate matter (PM2.5) can be genuinely useful for tracking trends — for example, confirming that a range hood reduces cooking-related particulates, or that a new piece of furniture is off-gassing noticeably. They're a lower safety priority than radon and CO detection and are more about comfort optimization than acute risk.

Ventilation is the common thread

Whether the concern is radon, VOCs, or general stuffiness, adequate fresh-air exchange dilutes whatever is accumulating indoors. Bathroom and kitchen exhaust fans, an HRV or ERV system in tighter modern homes, and simply opening windows when weather allows all reduce indoor pollutant concentrations broadly, even without addressing a specific source.