When Does a Fire Extinguisher Need to Be Hydrotested?

What Is Hydrostatic Testing?

Hydrostatic testing (hydrotest) is a pressure test that verifies the structural integrity of a fire extinguisher's cylinder. The cylinder is filled with water and pressurized to a level higher than its normal operating pressure to check for leaks, deformation, or failure. This test identifies cylinders that have been weakened by corrosion, physical damage, or manufacturing defects.

Hydrotest Intervals by Extinguisher Type

Stored-pressure dry chemical: Every 12 years

CO2 (carbon dioxide): Every 5 years

Wet chemical (Class K): Every 5 years

Pressurized water and water mist: Every 5 years

Halogenated agents (Halon, clean agents): Every 12 years

When Is Hydrotesting Required Sooner?

Regardless of the standard interval, a hydrotest is required immediately if the extinguisher shows visible dents, gouges, or weld damage, if it has been subjected to heat from fire exposure, if it has been dropped or subjected to significant impact, or if there is any visible corrosion that could compromise the cylinder wall.

What If the Extinguisher Fails the Hydrotest?

A cylinder that fails hydrostatic testing must be permanently removed from service and destroyed. It cannot be repaired or returned to service. We will document the failure and recommend a suitable replacement unit.

Who Can Perform Hydrostatic Testing?

Only trained and certified personnel using calibrated equipment may perform hydrostatic tests on fire extinguisher cylinders. This is not a test that can be performed by building staff. Our team is certified and equipped for all standard extinguisher types.