Tools and Materials
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What Are the Main Fire and Carbon Monoxide Threats?
While smoke and flames from a fire are often easy to see, a fire that begins in a vacant part of the house, in an attic, inside a wall or a fire that 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.
Carbon monoxide 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.
Carbon monoxide 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.
Choosing the Best Carbon Monoxide Alarms and Smoke Detectors
A combination smoke and carbon monoxide detector — also known as a smoke and carbon monoxide alarm — can warn you when either threat is present and help protect you and your family as well as your home.
- Battery-operated smoke and carbon monoxide detectors use built-in or replaceable batteries. Replaceable batteries for smoke and carbon monoxide detectors are usually 9-Volt or AA batteries.
- Hardwired smoke and carbon monoxide detectors require electrical connections at an available junction box. New hardwired devices should feature battery backup.
In addition to choosing a power type that works best for your home, look for features such as:
- Smart compatibility that works with many home management systems
- Wi-Fi connectivity that can send alerts to a mobile device
- Voice alerts that're easy to understand
There are different types of sensors available with smoke detectors:
- Smoke detectors with ionization sensors register a flaming fire more quickly.
- Photoelectric smoke detectors provide a faster response to smoldering fires.
Do You Need a Carbon Monoxide Detector Even If Your Home Does Not Use Gas?
Your home needs a carbon monoxide detector or alarm even if you don't have natural gas appliances or heating. Any device or equipment that burns fuel can be a source of carbon monoxide, including:
- A car, truck or a piece of gas-powered lawn equipment in the garage
- A propane, natural gas or charcoal grill
- A gasoline, natural gas or propane generator
- A wood fireplace or wood-burning stove
- A chimney that doesn't function properly
- Oil-burning, kerosene-burning or coal-burning heating devices
Installing combination smoke and carbon monoxide alarms helps protect your home and family from these potential carbon monoxide threats as well as from fire threats.
Where to Install a Carbon Monoxide Alarm and Smoke Alarm
Follow the manufacturer's instructions for placement of smoke and carbon monoxide alarms. Locations include:
- On each floor of the home
- In each bedroom
- In each hallway close to sleeping areas; if a hallway is longer than 40 feet, place devices at both ends
- At the top of stairways going to an upper floor
- At the bottom of stairways going to a basement
- In your living area
- At least 10 feet away from your stove or furnace
They should be mounted on the ceiling at least 6 inches from the wall or on the wall at least 6 inches below the ceiling.
Check your manual for installation locations to avoid and information on how far to install the alarms from furnaces, heaters, stoves, water heaters and other devices.
Some smoke and carbon monoxide alarms allow you to wirelessly connect compatible units so all linked units sound an alarm when one detects a threat. This functionality can warn of hazards in remote areas of the house. If you install linkable units, pay attention to the range and placement restrictions for the linking feature.
How Do You Install a Battery-Powered Smoke and Carbon Monoxide Alarm?
Follow the installation and maintenance instructions that came with your device. Here are the basic steps:
Instructions
Installing a Hardwired Smoke Detector
A hardwired smoke detector installation is an advanced project that’s best left to professional electricians or DIYers with extensive knowledge of wiring and electrical safety practices. Check local building codes and regulations before beginning to determine what’s required in your area. Even if you’re well versed enough in electrical work to do most of the job yourself, it’s always a smart idea to get an inspection from a pro.
How Do You Set Up and Maintain a Smoke and Carbon Monoxide Alarm?
Depending on the alarm model, there may be other procedures you need to follow, including:
- Wirelessly linking compatible units in your home
- Setting up voice notification and location features
- Setting up the unit to work with a home management system
- Using optional battery and mounting locks
In addition to weekly testing, a smoke and carbon monoxide alarm needs regular maintenance to keep it clear of dust. Don't use water, cleaners or other chemicals on the unit.
If the alarm does not have a built-in battery, use only battery types specified by the manufacturer. Write the installation date on the batteries with a permanent marker. Change them at least once every six months.
Keep your manual in a readily accessible location so you can reference it easily for instructions on replacing batteries, reprogramming it or interpreting notifications.
How Should You Respond to an Alarm?
Have an evacuation plan for your family so that everyone knows what to do in an emergency. Identify a single gathering point outside the home. Practice evacuation periodically, determining the fastest and safest paths to your gathering point.
If the alarm activates:
- Leave the house immediately.
- Make sure that all family members are out.
- Call 911 from a safe location to report the problem.
- Stay out of the house until emergency responders tell you it's safe to return.
If the problem is carbon monoxide, have a trained technician check any appliances that can generate the gas.
What Does a Beeping Smoke Alarm Mean?
Beeps and chirps from a smoke alarm or carbon monoxide alarm have different meanings, depending on sound, pattern and device model.
It's critical to check the manufacturer's instructions to understand the meaning of each alert. Your manual will explain the beeps and chirps for your specific alarm.
Here are some possible meanings:
- Pulsating beeps, a recurring pattern of beeps separated pauses or a continuous, shrill sound mean the alarm has detected a threat. Leave the home immediately and follow the other steps listed above in the How Should You Respond to an Alarm? section.
- Occasional chirps or beeps from a battery-operated alarm may indicate you need to replace the battery. If the chirping occurs after installing a new battery, make sure it's installed correctly and has good connections with the contacts on the alarm.
- Occasional chirps or beeps from a hardwired alarm may mean that the power has been interrupted and restored. If the beeping continues, have an electrician check the unit and power circuit. If the unit has a battery backup, it may mean you need to replace the battery.
- Some beeps and chirps mean the device itself has reached the end of its functional life and needs to be replaced. Check your unit's manual for its specific end-of-life signal.
How Often Should I Change My Smoke Alarm Battery?
Change the batteries in your smoke and carbon monoxide alarms at least every six months. If an alarm indicates low battery power, replace the battery or batteries immediately. Check your manual for details on low battery power alerts.
If you have an alarm with a 10-year, built-in battery, the battery should be designed to last the life of the alarm. Refer to your manual for details and the end-of-life signal so you'll know when to replace the device.
If your home has existing smoke and carbon monoxide detectors, you need to know if they're battery-operated or hardwired. Carefully remove the device from the mounting bracket. A battery-operated device won't have visible wiring. A hardwired unit will have wiring that runs into the ceiling or wall.
Hardwired units may have backup batteries. These need to be replaced just like those in battery-powered devices.
What Are Other Smoke and Carbon Monoxide Alarm Considerations?
Make sure you and your family are familiar with the smoke and carbon monoxide alarms in your home:
- Learn the available features and how to use them.
- Understand how the units respond to threats so you can quickly interpret alarms.
- Learn how the device indicates situations such as loss of power, low batteries and end-of-life.
- Know the lifespan and initial power-up date of each unit and replace units at the proper time. Some units alert you when they reach the end of their lifespan.
- After an alarm, follow manufacturer's instructions for resetting or replacing your device.