What are some common questions people have about carbon monoxide alarms?
Q: What does "Move to Fresh Air" mean?
A: This message is printed on your CO alarm as a clear reminder: if the alarm goes off, immediately move everyone to a well-ventilated area with fresh air.
Tip: Don’t unplug or move the alarm when it sounds. Leave it in place and get to safety first.
Q: Why didn’t the fire department or gas company find carbon monoxide after my alarm went off?
A: If your alarm sounded, it did detect carbon monoxide. There are a couple of reasons why nothing was found later:
• Fresh air cleared the CO before help arrived (especially if doors/windows were opened).
• CO levels fluctuate. Your alarm may have picked up a short-term spike that wasn't present when responders checked.
• Some alarms have a “peak level” button that shows the highest CO level since the last reset. This can help identify what happened.
Q: Will a CO alarm detect explosive gas leaks?
A: No. Carbon monoxide alarms only detect CO gas, not explosive gases like propane or natural gas.
• To detect explosive gas, use a separate explosive gas alarm, especially if you use natural or propane gas at home.
Q: Can I reset a plug-in CO alarm with the test/silence button?
A: Not fully. The test/silence button only temporarily silences the alarm. To reset it:
• Move the alarm to fresh air.
• Hold the silence button for 5 seconds.
• Allow time for the sensor to clear any lingering CO. You may need to do this more than once.
Q: Can I test my CO alarm in any other way?
A: No, only use the test button to check your alarm.
• Never use car exhaust or any CO source to test it — this can permanently damage the sensor and void your warranty.
Q: Where should I install my carbon monoxide alarms?
A: For the best protection:
• Install one outside each bedroom or sleeping area.
• For maximum safety, place one in every bedroom.
• Put one on each level of your home, including the top of basement stairs.
• Keep alarms 15–20 feet away from fuel-burning appliances.
• Place them at least 10 feet away from bathrooms and humid areas.
Q: Where not to install a CO alarm?
A: Avoid these spots:
• Garages, kitchens, or furnace rooms
• Humid, dusty, or greasy areas
• Areas with extreme temperatures (attics, crawl spaces, porches)
• Behind curtains or furniture
• Near fans, vents, windows, or open-air flow
• These conditions can interfere with the alarm’s ability to detect CO properly.
Q: Can I connect CO alarms with smoke alarms?
A: In many cases, yes. However, always check the user manual to make sure they’re compatible.
Q: What are some common sources of carbon monoxide?
A: CO is a colorless, odorless gas produced when fuel doesn't burn completely. Common sources include:
• Cars running in attached garages
• Furnaces, fireplaces, stoves, and ovens
• Water heaters, dryers, and space heaters
• Portable generators or grills (used indoors)
• Even well-functioning appliances can become hazardous if they're not vented properly or if fresh air is limited.
Q: What levels of CO trigger an alarm?
A: CO levels are measured in parts per million (ppm). According to UL2034 standards:
• 70 ppm – Alarm within 60 to 240 minutes
• 150 ppm – Alarm within 10 to 50 minutes
• 400 ppm – Alarm within 4 to 15 minutes
Tip: Alarms are not required to sound at 30 ppm, even over long periods.
Q: Is carbon monoxide heavier than air?
A: No, CO mixes evenly with air. So, install alarms in spots where they stay clean and out of reach of pets or kids. Follow the user manual for the best placement.