Positive isolation philosophy/ methodology

[frogcurry]

Does anyone know of any standards that define acceptable designs and possible issues with positive isolation such as DBB, spectacle blinds, etc? The only one that I know of Is NORSOK P-001 section 6.

 

[liberoSimulation]

If I understand your question well, I would say from my experience that positive isolation is required for any utility line connected to a process line (like hydrocarbon) where two valves with bleed shall be installed in the utility line to avoid contamination and to avoid any safety problem (such as contact Air with Hydrocarbon). Positive isolation with valve and blind is also required for the equipment where possible maintenance work is to be done for such equipment where plant is in normal operation (like dryer and reactors where replacement of catalysts is possible during life of the plant).
Hope this would give you light on your question.

Regards

 

[vzeos]

frogcurry,

See the attached thread.

thread408-48267