Corrosion on Portable Fire Extinguishers

Background

An employee was killed when he used a portable fire extinguisher to put out a small fire. Corrosion on the bottom of the fire extinguisher was serious enough that the extinguisher case ruptured when it was activated, and parts struck the fire watch in the chest. A similar incident occurred in 1988.

The Hazard

This fire extinguisher had a rubber boot or cap to protect the bottom of the cylinder case. Moisture had seeped in between the rubber and outside cylinder wall and caused the cylinder to corrode inside the boot. Over time, this corrosion weakened the cylinder and it ruptured when the internal CO2 cylinder was activated. Other extinguishers of this type have been found to have the same type of corrosion underneath the rubber boot.

Recommendation

If your fire extinguishers have rubber or plastic boots or caps and are located in potentially corrosive environments such as:

• Extinguishers stored outside, unprotected from the weather
• Extinguishers stored in wet or damp environments
• Extinguishers stored near marine facilities or other waterfront buildings, especially those located near salt water

1. Immediately remove the extinguisher from service and have it inspected by the vendor or other qualified person.

2. Include inspecting the bottoms of this type of extinguisher as part of the monthly fire extinguisher inspection.

3. Remind employees that they must stand away from portable fire extinguishers during re-charging.