By Ed Curran

(CBS) — Smoke and carbon monoxide detectors are pretty inexpensive life insurance. CBS 2’s Ed Curran says you may remember to change your battery when you change your clock, but have you given any thought to changing your detector?

The fire at the Hancock Building this weekend was a heart-stopping high rise blaze. Fire department officials say it was started by a candle.

But it’s the fear of fire in your home, and the threat of carbon monoxide from a faulty furnace, that sends Ed up a ladder to test his detector.

His works just fine, but your detector has a life span. Smoke detectors are good for about 10 years. Older carbon monoxide detectors last only five. The back of your detector should have the date it was built, or an expiration date. Replacing the batteries may not be enough.

Batteries are expensive. The latest technology are smoke and carbon monoxide detectors that have batteries that’ll last ten years. At the end of that time you simply buy another one, and the unit will warn you when it’s running out of gas.

The price? About $25. Pro-rate that over its ten year life and these new detectors cost you about 21-cents a month.

So check the back of your detector. If it’s too old, pick up a new one. Test your new detectors a couple of times a year. But it’ll be 2025 before you need a new one.

There should be smoke detectors in every bedroom and a carbon monoxide detector on every floor. At these prices, it’s an inexpensive way to sleep a little better at night.