What are the legal requirements for maintaining an emergency oxygen unit?
Federal regulations (under the DOT) regarding refillable oxygen cylinders require hydrostatic testing of the cylinder every five (5) years, but only if and when the cylinder is refilled. This is accomplished by the refilling agency. Unless you are a certified refilling site, you should NOT refill your own cylinders. Periodic (5 yrs.) confirmation of the regulator flow parameters is also required and can be done at the same time.