Steel and Aluminum cylinder require hydrostatic retesting every 5 years, with no set cylinder life span as long as cylinder passes test.
Composite cylinders, hoop wrapped (fiberglass wrapped aluminum cylinders), fiberglass and Kevlar, require hydrostatic retesting every 3 years. These cylinders have a 15 year life span from the date of manufacture.
Most Carbon Fiber Cylinders require hydrostatic retesting every 5 years. These cylinders have a 15 year life span from the date of manufacture.
EDDY Current Testing
EDDY Current testing uses electromagnetic induction to detect flaws in the cylinder neck. EDDY Current testing is required on aluminum cylinders made of the aluminum alloy 6351-T6. Front Range Fire Apparatus uses the Visual Plus 3 EDDY Current test equipment.