Carbon monoxide detector
Carbon monoxide gives you no warning of its own
Radon is a leading cause of lung cancer among people who have never smoked, and it cannot be detected without an instrument. The EPA's action level is 4 pCi/L. Levels shift with the season, the weather and how well a house is ventilated, which is why a continuous monitor catches what a single test kit can miss.
What to do
- Read the actual number, not just whether the indicator light is on.
- Below 4 pCi/L is within the EPA's guidance.
- At or above 4 pCi/L, arrange a follow-up test and look into mitigation.
- Check the reading a few times a year - levels change with the seasons.
| Category | Detection & monitoring |
|---|---|
| Where | In-home device |
In an emergency, always call 911.
Also in detection & monitoring
Smoke detector
Ten years from the date on the back, not the day you installed it
Is there one of these near you?
A ResQ‑R badge on one of these carries this same guidance, plus where that particular one is and who looks after it. Point your phone’s camera at the Dalmatian’s spots — no app, no account. See how it works.