RALEIGH, N.C. (WNCN) — When it comes to keeping safe, many tools are used including expiration dates on products.

However, when it comes to some common items we use or rely on — we may not realize they can expire.

Expiration dates on things like food are pretty obvious.

Look at the label and you can see when it’s no longer good, but there are lifesaving things around your house that don’t have expiration dates — but do expire.

SMOKE DETECTORS

If you have a battery-operated smoke detector, you probably know the batteries expire and need to be changed on a regular basis.

However, the unit itself also expires because the components inside of them degrade over time.

You get about 10 years on a smoke detector. You need to check the back side of the unit to find out when it should be replaced. The same goes for carbon monoxide detectors. They wear out too.

FIRE EXTINGUISHERS

Take fire extinguishers. They are pressurized and eventually, even though they are sealed, start to lose pressure. Also, the operating parts tend to corrode or break.

If you’ve had your unit for 12 years or more, replace it.

BIKE HELMETS

If they’ve been in an accident, it’s pretty obvious they need to be replaced, but even without an accident — they don’t last forever.

Even if you’re an infrequent rider, you need to pay attention to the bike helmet.

The foam components inside the helmet degrade over time and the outside portion of the unit can separate from the liner.

You should replace them every 5 years and that goes for motorcycle helmets too.

CHILD SEATS

They’re expensive and you may be tempted to reuse one or buy a used version, but keep in mind that those seats have a limited life span.

As they grow older the materials used to cushion the child may no longer work effectively and older seats may no longer meet the latest safety standards.

They’re only good for about six years, after that they need replacement.

SUNSCREEN

As we head into fall, you might decide you want to stockpile all that sunscreen you didn’t use.

That may not be such a “hot” idea if the sunscreens were purchased a few seasons ago.

Sunscreen starts to lose its potency after three years, not because the package is open but rather, after a certain point the ingredients in the product go bad even if the container is still factory sealed.