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Change your clocks, batteries

November 2, 2023

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WASHINGTON, DC—The long-standing “Change Your Clocks, Change Your Batteries” campaign encourages the public to change their smoke alarm batteries and test their carbon monoxide alarms when turning back clocks in the fall.

On Nov. 5, states throughout the U.S. will turn their clocks back at the end of Daylight 

Savings Time. Many people will use this opportunity to test their home’s smoke alarms and carbon monoxide detectors as well.

Because working smoke alarms are a critical element of home fire safety, the National Fire Protection Association supports all efforts to reinforce the importance of working batteries. However, today’s smoke alarms are not all designed the same, making battery messaging more nuanced.

Following is information to help make sure all smoke alarms have working batteries, accounting for the multiple types of smoke alarms on the market and their varying battery requirements:

  • Smoke alarms with non-replaceable 10-year batteries are designed to remain effective for up to 10 years. If the alarm chirps, warning that the battery is low, replace the entire smoke alarm right away.
  • Smoke alarms with any other type of battery need a new battery at least once a year. If that alarm chirps, warning the battery is low, replace the battery right away.
  • When replacing a battery, follow manufacturer’s list of batteries on the back of the alarm or manufacturer’s instructions. Manufacturer’s instructions are specific to the batteries (brand and model) that must be used. The smoke alarm may not work properly if a different kind of battery is used.
  • Smoke alarms are only good for a maximum of 10 years; after that, the sensor is degraded and is not reliable. When changing or checking the alarm battery, check the date of manufacture of the alarm and replace it if it is more than 10 years old.
  • Smoke alarms save lives. Smoke alarms that are properly installed and maintained play a vital role in reducing fire deaths and injuries. If there is a fire in your home, smoke spreads fast and you need smoke alarms to give you time to get out. 

Here's what you need to know!

  • Closed doors may slow the spread of smoke, heat and fire. Install smoke alarms in every sleeping room and outside each separate sleeping area. Install alarms on every level of the home.
  • Smoke alarms should be interconnected. When one sounds, they all sound.
  • Large homes may need extra smoke alarms.
  • Test your smoke alarms at least once a month. Press the test button to be sure the alarm is working.
  • Today’s smoke alarms are more technologically advanced to respond to a multitude of fire conditions, yet mitigate false alarms.
  • When a smoke alarm sounds, get outside and stay outside.
  • Replace all smoke alarms in your home every 10 years.

Carbon monoxide

As leaves change color, days grow shorter and the nights get colder, we switch our thermostats to heat. For those who don’t heat with electricity, this switch can be deadly. Why? Heat sources that use natural gas, propane, butane, coal, kerosene, wood or oil depend upon efficient mixtures of air and fuel to provide complete combustion. If there is a problem and the fuel doesn’t burn completely, carbon monoxide, a deadly colorless, odorless, invisible gas is produced.

Effects: Carbon monoxide reduces the availability of oxygen in the blood and can cause death by asphyxiation.

Symptoms range from mild headache, nausea and dizziness to loss of consciousness and death. Judgement and thought processes become impaired, and victims are often unable to react in time to save themselves. Children, people with heart problems or respiratory illness, and the aged are particularly sensitive to carbon monoxide’s effects.

Safety tips

  • CO alarms should be installed in a central location outside each sleeping area and on every level of the home and in other locations where required by applicable laws, codes or standards. For the best protection, interconnect all CO alarms throughout the home. When one sounds, they all sound.
  • Follow the manufacturer’s instructions for placement and mounting height.
  • Choose a CO alarm that has the label of a recognized testing laboratory.
  • Test CO alarms at least once a month; replace them according to the manufacturer’s instructions.
  • If the audible trouble signal sounds, check for low batteries. If the battery is low, replace it. If it still sounds, call the fire department.
  • If the CO alarm sounds, immediately move to a fresh air location outdoors or by an open window or door. Make sure everyone inside the home is accounted for. Call for help from a fresh air location and stay there until emergency personnel.
  • If you need to warm a vehicle, remove it from the garage immediately after starting it. Do not run a vehicle or other fueled engine or motor indoors, even if garage doors are open. Make sure the exhaust pipe of a running vehicle is not covered with snow.
  • During and after a snowstorm, make sure vents for the dryer, furnace, stove and fireplace are clear of snow build-up.
  • A generator should be used in a well-ventilated location outdoors away from windows, doors and vent openings.
  • Gas or charcoal grills can produce CO—only use outside.