Smoke detectors and carbon monoxide alarms help you prepare for the threats of fire and carbon monoxide. Use this guide to learn about the different types available.
Smoke and flames from a fire are easy to see, but a fire that begins in a vacant part of the house or starts in the middle of the night can spread undetected. Once a fire starts, it can grow quickly.
Carbon monoxide (CO) poses an invisible threat. It's a colorless, odorless gas produced by any fuel-burning appliance or fixture — such as a furnace, water heater or fireplace. Carbon monoxide can build up in the home from malfunctions or improper venting in these devices. It can also accumulate if the home is sealed for energy efficiency, reducing the exchange of inside and outside air. An attached garage in which a vehicle is running can also allow carbon monoxide to enter the home. The gas is dangerous because it replaces the oxygen in the air and, when inhaled, creates a toxic compound in your body. For more on carbon monoxide, see the Centers for Disease Control and Prevention Carbon Monoxide Poisoning information.
Smoke detectors and carbon monoxide alarms are two tools that can help you protect your home and family from these threats, even when they occur in remote areas of the home or at night when everyone is asleep. You can purchase the devices separately or as combination units.
Keep vents — such as those for the dryer and furnace — and fireplace chimneys clear. Have any appliance that burns fuel inspected yearly.
Both smoke detectors and carbon monoxide alarms are available in hardwired models that connect to your home wiring or battery-operated models. Carbon monoxide alarms are also available as models that plug into home electrical outlets. Look for battery backup capability in devices that run off of a home electrical system, to keep the unit functioning during a power outage. Some smoke detectors and carbon monoxide alarms feature built-in power cells that are designed to last the life of the device.
The lifespans of smoke detectors, carbon monoxide alarms and combination units differ based on factors such as device type, model and where they're installed. See the manual for specific information on when to replace a unit. In general, replace a smoke detector after no more than 10 years and a carbon monoxide alarm after no more than 5 years. Combination unit lifespan typically ranges between 5 and 7 years. If a device indicates an end-of-life condition, replace it immediately.
Don't confuse the device lifespan with battery life. If a battery-powered unit doesn't have a built-in power cell, replace the batteries at least once every six months. Write the installation date on the batteries with a permanent marker. Replace them at once if the device signals a low-battery condition. Use only battery types specified by the manufacturer.
Follow the manufacturer's instructions for placement of smoke detectors and carbon monoxide alarms. Locations include:
Check your manual for installation locations to avoid and information on how far to install the devices from furnaces, heaters, stoves, water heaters and other appliances and fixtures.
See Install a Smoke and Carbon Monoxide Alarm to learn general steps for installing a battery-operated smoke detector and carbon monoxide alarm.
Follow the device manufacturer's instructions for installation, use, testing and maintenance.
Smoke detectors and carbon monoxide alarms may be mandatory in your area. Check local codes for requirements on placement and the number of units that must be present in a home.
Make sure you and your family are familiar with the smoke detectors and carbon monoxide alarms in your home: