The National Institute for Occupational Safety and Health (NIOSH) has issued a safety alert informing users of self-contained breathing apparatus (SCBA) that certain high-pressure aluminum seamless and aluminum composite hoop-wrapped cylinders made of aluminum alloy 6351-T6.

These SCBA cylinders are susceptible to sustained load cracking (SLC) in the neck and shoulder areas. If such cracks are not detected during visual inspection, NIOSH warns that cylinder rupture can occur, especially during filling. These ruptures can result in death, serious injury, and/or property damage.

NIOSH recommends that these cylinders be given special attention to eliminate the risks associated with such cylinder ruptures. These affected cylinders are used on a number of manufacturer’s NIOSH-approved SCBA and are available in a number of sizes and durations ranging from five to 30 minutes.

The complete NIOSH User Safety Notice is available here. It contains specific information on how to identify these cylinders and what precautions need to be implemented.

Fire departments must determine if they are using these cylinders and immediately begin the prescribed actions.