LDE / PVS Program FAQ:

LDE Operations:

1.     What is the role of the LDE Operations group?

a.     The role of the LDE Operations group is to inspect, consult and certify LDE located on GSFC. The LDE Operations Technician’s role is to ensure LDE are safe to use by inspecting the equipment according to National and NASA standards.

2.     When a piece of equipment fails an inspection, who is responsible for fixing it?

a.     When a piece of equipment fails an inspection or fails during use, it is the owner’s responsibility to ensure the equipment is repaired so that it can be safely used. After the repair, the owner should contact the LDE Operations group so that an inspection can be performed to certify the equipment for use.

PVS Operations:

1.     When is a relief valve required?

a.     Anytime the maximum gas pressure possible exceeds the Maximum Allowable Working Pressure (MAWP) of any component in the system.

2.     What is a system, and what gets certified by the PVS Program?

a.     A system is a network of components from source gas pressure to final end use. The PVS Operations group is responsible for certifying the entire scope and not just single components. Effectively, we help ensure that all links in the chain fit together safely.

3.     The tag on my relief valve has expired, how do I fix this?

a.     The valve may still be good for a total of 5 years from the previous inspection date. Contact the PVS Operations group to evaluate your system and updating the expiration date before you replace/re-test the valve.

4.     I heard proportional relief valves are no longer acceptable, is this true?

a.     Not entirely. If you can provide sufficient data that guarantees the proportional relief valve has enough capacity to relieve the required load upon over-pressurization, then the valve may be acceptable in your system and no modifications/replacements to the valve are required. Otherwise they should not be used as the primary safety device on your system.

5.     If a system is using inert gas and is less than 150 psig, is it excluded from the PVS Program?

a.     Yes/No. Certain components within the system can be considered excluded from requiring analysis and regular maintenance intervals under these conditions, but the system as a whole is still considered a pressurized system and therefore must be checked and certified by the PVS Program.