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Smoke Alarm

Survey data shows that the public has many misconceptions about smoke alarms, which may put them at increased risk in the event of a home fire. For example, only a small percentage of people know how old their smoke alarms are, or how often they need to be replaced.

As a result of those and related findings, we’re addressing smoke alarm replacement this year with a focus on these key messages:

  • Smoke alarms should be replaced every 10 years.
  • Make sure you know how old all the smoke alarms are in your home.
  • To find out how old a smoke alarm is, look at the date of manufacture on the back of the alarm; the alarm should be replaced 10 years from that date.

NFPA Fire Prevention Information


Why do I need to replace my smoke alarms every 10 years?

It is required that smoke alarms be replaced within 10 years according to NFPA 72, National Fire Alarm and Signaling Code. They are not permitted to remain in use longer than 10 year from the date of manufacture. Also, the manufacturer’s instructions for most smoke alarms state they are to be replaced when they fail to respond or after 10 years. Combination smoke/carbon monoxide alarms must be replaced when the end-of-life signal sounds or 10 years after the date of manufacture, whichever occurs first.

How do I identify my smoke alarm’s date of manufacture?

Remove the alarm from the ceiling or wall. Look at the back or side of the alarm for the date of manufacture.

How do I replace a battery-powered smoke alarm?

Remove the smoke alarm from the ceiling by twisting the alarm to remove it from the ceiling plate. It is best to replace the alarm with the same manufactured alarm. The new alarm from the same manufacturer can be placed on the ceiling or wall plate. Twist to secure the alarm. Test the alarm to be sure it is working. If you are replacing with an alarm from a different manufacturer, you will need to remove the old ceiling plate and install the new ceiling plate included with the new alarm. Place the alarm over the ceiling plate and twist to secure the alarm. Test the alarm to be sure it is working.

How do I replace a hard-wired alarm?

If you know how to work with electrical wiring, follow manufacturer’s instructions. Make sure you have turned off the electricity to the smoke alarm before you begin replacing the alarm. Otherwise, contact a qualified electrician to replace hard-wired smoke alarms.

How do I install a hard-wired smoke alarm?

Contact a qualified electrician to install hard-wired smoke alarms.

If you need a smoke detector, a replacement battery, or assistance in testing or installing your detector, please contact the Fire Department at (919) 217-2270 or Contact by E-mail.