Nest Protect sounds an alarm and sends a message to the Nest app or Google Home app when it detects that carbon monoxide (CO) levels have reached an emergency level. It’s important that you always respond to a CO emergency by evacuating the house and calling emergency services.
When the alarm sounds, move to fresh air even if the CO level shown in the app seems low. CO levels may continue to rise rapidly after the alarm is triggered, so the level shown in the app may not reflect the current level of CO in your home.
What to do if carbon monoxide is detected in your home
The danger of carbon monoxide (CO) depends on a number of variables like the amount of CO in the air, how long you were exposed to that level, and your health and level of activity. CO poisoning can result from being around high levels of CO for a short amount of time, or lower levels of CO for a longer amount of time.
After the event, Nest Protect reports the highest level of CO that it detected. This is the peak CO level. You can also find the peak CO level in Protect History. This information can be used by a fire safety professional, or an experienced technician, to help identify the source of the CO.
Nest Protect isn't a low-level carbon monoxide monitor so it alerts you to carbon monoxide only in a Heads Up or Emergency Alarm event.
Individuals with certain medical problems should consider using detection devices with lower COHb alarm capabilities and warning devices which provide audible and visual signals for carbon monoxide concentrations under 30 ppm.
For more information about alarm thresholds under American National Standard ANSI/UL 2034, refer to the Carbon Monoxide (CO) Precautions section in your Nest Protect User’s Guide. Download your Nest Protect User’s Guide.
For further information, please consult a qualified medical professional or go to the World Health Organization’s document on pollutants.