Answer: D
If you take care of a cylinder with careful handling, regular maintainance, and by keeping it clean and dry to reduce the risk of rust, it is quite possible that the cylinder can have a life span of many decades. We have many cylinders that come in for regular checkups that have been in service for 40, 50 or more years.
Call for more ideas or to get your pressurized cylinders checked at (330) 762-3343 or email info@autotechfire.com.