When should an SCBA air cylinder be replaced?

An SCBA air cylinder should be replaced when it drops below 90% of its rated capacity because maintaining a sufficient air supply is critical for the safety of the user. An air cylinder that is not fully charged or has lost significant capacity can compromise the user's ability to operate in hazardous conditions where breathable air is not available.

Using the 90% threshold ensures that the user has enough air supply to handle emergencies and provide a safe margin for escape or extended operations in environments that require the SCBA. This practice aligns with safety standards that prioritize preparedness and the health of the personnel using SCBA.

It's crucial to regularly check the pressure gauge on the cylinder to monitor its capacity, as using a cylinder with inadequate air can lead to life-threatening situations. Thus, replacing the cylinder at the 90% threshold is a proactive approach to ensure operational readiness and personal safety.