Carbon Monoxide Alarms

Carbon monoxide (CO) is a colourless odourless gas that mixes freely with the air.

CO alarms are important life saving devices that are designed to provide early warning to you and your family during potentially life threatening situations. It is imperative that CO alarms are installed in the correct location, which is near the sleeping area.

However, most people take these devices for granted.

Did you realize that while you are asleep, your senses, including smell, are greatly diminished? Or that carbon monoxide, either due to a faulty appliance or as a result of smoke in a fire, can actually put you into a deeper sleep, one that you may not awaken from? These are just two of the reasons that every home should be equipped with properly installed and maintained CO alarms. 

Watch a video on Carbon Monoxide.


Common Sources of Carbon Monoxide - In the Home

Carbon Monoxide Safety in the home

Common Sources of Carbon Monoxide - In Condos and Apartments

Carbon Monoxide safety in condos

Carbon Monoxide Alarm Requirements


If your home has any oil, propane or gas-burning appliances, furnace or water heater, a wood or gas fireplace, or an attached garage or carport, you must have working carbon monoxide alarms installed near sleeping ares.  This now applies to ALL residential buildings.

Multi-unit residential buildings

Multi-unit residential buildings have additional requirements. Carbon monoxide alarms are required to be installed in the service room and adjacent to the sleeping areas in the suites that share a common wall, ceiling, or floor with the service room.

Carbon monoxide alarms must be maintained in operating conditions at all times and may not be disabled.

Tenants must be supplied copies of the maintenance instructions for the carbon monoxide alarms. Tenants are also required to notify the landlord as soon as they become aware that a carbon monoxide alarm becomes desconnected or is not operating or is impared.

Carbon monoxide alarms must be replaced within the time frame outlined in their manufacturers instructions.

Testing of carbon monoxide alarms shall consist of a test conducted by the landlord annually, after the battery is replaced and if there is any change to the electrical circuit connected to the carbon monoxide alarm.     

For detailed information regarding the requirements for the installation of Carbon Monoxide alarms, please contact the City of St. Catharines Fire Prevention office at 905-688-5601 ext 4224. You may also visit the Technical Standards and Safety Association or visit the Ontario Fire Marshals website.

Additional information

Cost of a Carbon Monoxide alarm

Between $25 to over $100 depending on the model and different features.

Where to buy

They can be purchased at most hardware stores and other big box stores.  The St. Catharines Fire Service does not sell carbon monoxide alarms.


Carbon monoxide alarms sound different from smoke alarms. Sounds vary depending on the model.

Carbon monoxide symptoms

Flu-like symptoms, without the fever.

If your carbon monoxide alarm activates and people are showing signs of carbon monoxide poisoning you should

Immediately have everyone move outdoors and call 911.

If your carbon monoxide alarm sounds, and no one is showing symptoms of carbon monoxide poisoning you should

Check to see if the battery needs replacing or the alarm has reached its "end of life" before calling 911.

Copyright © 2014 The Corporation of the City of St. Catharines