Another significant drawback to conventional testing methods is that they
render the valve unavailable during testing if a real safety issue is encountered.
Conventional valve testing procedures also put the burden on
technicians to manually return safety valves to their proper operating mode
after completing the tests. If an emergency were to occur during the testing
procedure, or if a safety valve were to be left with its range of motion restricted,
the valve would be unavailable to prevent a fire or explosion
during a process upset. Because of these risks, and its highly laborintensive
nature, many end users feel they must improve their safety valve
testing procedures