Most manufacturers say that well-maintained fire extinguishers can last up to twenty years. The problem for most people? You’re not sure exactly when you got your extinguisher. So, do fire extinguishers expire?
The truth is that most fire extinguishers do not come with an expiration date, and it can be challenging to know exactly when to replace your fire extinguisher. There is no exact, set number of years that you can have an extinguisher before it is considered “expired.”
More important in determining when to replace a fire extinguisher is how well it has been maintained. Over time, factors such as damage, rust and corrosion can cause a fire extinguisher to lose its ability to operate properly. This is why it’s extremely important that your extinguishers be inspected and tested at the proper intervals.
Perhaps the most important factor is the hydrostatic test. Hydrostatic testing measures the integrity of the fire extinguisher’s cylinder, which is under constant pressure. If an extinguisher fails this test, it is unsafe and should be taken out of service immediately.
Just as the fire extinguisher itself typically doesn’t expire, neither do the contents inside. Extinguishing agents are usually filled with water or chemical material that is pressurized with an expellant gas. While these materials don’t expire, the fire extinguisher can become depressurized over time, and the lack of pressure causes the extinguisher to become inoperable.
There are certain types of fire extinguishers that are now obsolete. If, for some reason, you still own one of these, it could be considered “expired.” Fire extinguishers become obsolete when the technology is so significantly improved that codes and requirements change. NFPA-10 provides guidelines for which types of extinguishers are considered obsolete and should be removed from service.
Types of Obsolete Fire Extinguishers:
- Soda Acid
- Chemical Foam
- Vaporizing Liquids (Carbon Tetrachloride)
- Cartridge-operated water
- Cartridge-operated loaded stream
- Copper or brass shell (excluding pump tanks) joined by soft solder or rivets
- Carbon dioxide extinguishers with metal horns
- Solid charge type AFFF (paper cartridge)
- Pressurized water extinguishers manufactured prior to 1971
- Any extinguisher that needs to be inverted to operate
- Any stored pressure extinguisher manufactured prior to 1955
- Any extinguisher with 4B, 6B, 8B, 12B, and 16B fire ratings
- Stored-pressure water extinguishers with fiberglass shells (pre-1976)
- Stored-pressure dry chemical extinguisher manufactured prior to October 1984
In addition to the types of extinguishers listed above, any fire extinguisher that can no longer be serviced in accordance with the manufacturer’s maintenance manual, or was made by a company that is no longer in business, is considered obsolete and should be removed from service.
With proper care and maintenance, portable fire extinguishers can provide years of reliable protection.