How often are SCBA cylinders hydrostatically tested and what is the purpose of these tests?

• A. Every 5 years to confirm structural integrity of the high-pressure cylinder and ensure safe air containment.
• B. Annually to ensure constant readiness.
• C. Every 3 years to minimize downtime.
• D. Only after damage is suspected.

Answer: (A)

Hydrostatic testing examines the physical durability of high‑pressure SCBA cylinders. These cylinders hold breathable air at thousands of psi, so hidden flaws like cracks or thinning walls can develop over time with use and aging. The test fills the cylinder with water and increases the pressure above the normal service pressure (typically to about 1.66 times that pressure) to stress the cylinder walls. If the cylinder can withstand this higher pressure without leaking, deforming, or failing, it’s considered safe for continued service for the next interval. If any defect is found, the cylinder is deemed unsafe and taken out of service or repaired if possible. This testing interval is set at five years to ensure safety while avoiding unnecessary downtime, since regular visual checks alone can miss internal flaws.