Piping Related Abbreviations (i)

ISBL is an abbreviation of In Side Battery Limits.
ISBL is functional-based and refers to equipment and other components that are solely dedicated to a single process whether or not the equipment is physically located within the geographical boundaries of the unit.

ISO is an abbreviation of ISOmetric (piping drawing).

ITP is an abbreviation of Inspection Test Plan.
An Inspection Test Plan (ITP) is a commonly required document that you'll need to submit with your construction quality control plan. Whether you're working on a private sector or government contract, clients today all want to see your inspection test plan. They want to know exactly what inspections and tests you'll be forming to control quality on their project.