MSS Standard SP-61, from the Manufacturers Standardization Society, establishes leakage allowances and provides guidance for testing valves typically used in “full open” and “full closed” service, such as check, isolation, and stop valves. It is not intended for use with control valves. The current version of MSS SP-61 was released in 2013.


MSS SP-61 covers shell and seat closure pressure testing of valves.


MSS SP-61 specifies the following tests:



Production pressure test
  • Closure member test
  • Shell leakage test
Verify the valve’s pressure containing capability
Shell leakage test
Verify the pressure containing capability of the external pressure boundary
Seat and closure member test
Verify performance of flow regulating elements within the valve
No visible leakage
Verify that there is no visible weeping (liquid test) or bubbling (air test)


A full copy of MSS SP-61, with complete testing procedures and specifications, can be purchased from the Manufacturers Standardization Society.

This entry was posted in The Valve Expert, Valve Leakage, Valve Standards and tagged , , , . Bookmark the permalink.