If your carbon monoxide (CO) alarm is sounding, treat it as a genuine emergency:
To stop your detector from beeping, first identify the sound pattern to determine if it is a true emergency, a low battery, or an end-of-life warning.
Call 911 First for Any Emergency Alarm
A continuous, loud alarm means carbon monoxide has been detected at a dangerous level. If your detector is sounding this type of alert: Evacuate everyone immediately, including pets. Call 911 from outside the building or from a neighbor's phone.
If your carbon monoxide alarm is going off and you want to turn it off, most CO detectors have a "silence" or "reset" button that will temporarily stop the alarm. Locate this button (usually on the front or side of the unit) and press it according to the manufacturer's instructions.
Yes, but it will not sound the same as an emergency. A low battery triggers a single chirp or beep every 30 to 60 seconds, whereas a true emergency sounds in a loud, continuous pattern of 4 quick beeps.
While it's important to call 9-1-1 if your CO alarm is sounding continuously without stopping, a CO alarm that chirps every 30 seconds is not an emergency. It probably means your CO alarm has reached its end of life and should be replaced. CO alarms have a life expectancy of around seven years.
It is also a good idea to know the signs of a potential CO problem:
A carbon monoxide detector will emit an emergency pattern of 4 loud, continuous beeps in a row, followed by a pause, repeating until the CO levels drop or the alarm is reset.
You can temporarily unplug a carbon monoxide (CO) detector to stop an annoying alarm or low-battery chirp. However, never leave the device unplugged permanently. Since CO is an invisible and odorless gas, unplugging the detector without replacing it leaves you completely unprotected against this deadly hazard.
Carbon monoxide (CO) false alarms are most frequently caused by expired sensors (usually 5–7 years), low or dead batteries, or dust and debris clogging the sensor chamber. Other common culprits include high humidity, cooking fumes, or the off-gassing of household chemicals and aerosols.
Three quick beeps on a carbon monoxide (CO) detector typically signal an internal malfunction or that the unit is reaching the end of its lifespan and needs to be replaced.
If your carbon monoxide alarm is beeping, immediately get out of the building and call the relevant helpline for the fuel type. The gas emergency helpline is 0800 111 999. Call a registered engineer to check all your fuel-burning appliances.
A carbon monoxide (CO) detector itself is typically white or off-white to blend into walls or ceilings. However, its indicator lights mean the following:
A carbon monoxide (CO) alarm beeping 4 times in a row—followed by a pause, then repeating the cycle—indicates dangerous levels of gas are present. This is a life-threatening emergency.
If your carbon monoxide (CO) alarm is sounding, treat it as a genuine emergency:
How long carbon monoxide takes to affect you depends entirely on the concentration of the gas in the air and length of exposure. In high concentrations, severe poisoning can occur in under five minutes. In lower concentrations, it may take one to two hours to show symptoms, or even weeks for low-level exposure.
Even if the alarm has stopped, get everyone out of the home to a place with fresh air. Contact 911 or your local fire department to report the incident. They can come to your home with equipment to measure CO levels and ensure it is safe to re-enter.
Because carbon monoxide (CO) is an invisible, odorless, and tasteless gas, you cannot detect it with your senses. You can only recognize you are breathing it in by watching for "flu-like" symptoms (without a fever), or by relying on Carbon Monoxide Alarms to warn you.
The OSHA personal exposure limit (PEL) for CO is 50 parts per million (ppm). OSHA standards prohibit worker exposure to more than 50 parts of CO gas per million parts of air averaged during an 8-hour time period. The 8-hour PEL for CO in maritime operations is also 50 ppm.
A pattern of 5 beeps every 30 seconds usually indicates that your carbon monoxide (CO) detector has reached its "End-of-Life". This means the internal sensor has expired and the unit can no longer safely detect CO gas.
One of the most common early symptoms of carbon monoxide (CO) poisoning is a headache, often described as dull or persistent. Because CO is odorless and colorless, these early signs are frequently mistaken for the flu or food poisoning.
Clearer symptoms of carbon monoxide poisoning can include:
You can't self-diagnose carbon monoxide poisoning. If exposure is suspected, immediately get out of the building and call 911 for assistance.