How is the acceptance criteria for line tightness often expressed?

How is the acceptance criteria for line tightness often expressed?

• A. As a fixed pressure threshold for the entire system.
• B. As a time-only duration of the test.
• C. As an allowable leak rate for the piping per length or per hour or per mile of piping, defined by the protocol.
• D. As a visual inspection standard.

Answer: (C)

Acceptance criteria for line tightness is expressed as an allowable leak rate for the piping, typically per length of piping or per hour (or per mile) of piping, as defined by the protocol. This provides a quantitative, scalable standard that directly relates to how much leakage is acceptable, so the test outcome reflects actual leakage behavior rather than just holding a pressure or riding out a set time. A fixed pressure threshold can hide leaks, and a time-only criterion doesn’t measure how much is escaping. Visual inspection alone can miss hidden or very small leaks, whereas a leak-rate limit gives a clear, objective pass/fail criterion.

Acceptance criteria for line tightness is expressed as an allowable leak rate for the piping, typically per length of piping or per hour (or per mile) of piping, as defined by the protocol. This provides a quantitative, scalable standard that directly relates to how much leakage is acceptable, so the test outcome reflects actual leakage behavior rather than just holding a pressure or riding out a set time. A fixed pressure threshold can hide leaks, and a time-only criterion doesn’t measure how much is escaping. Visual inspection alone can miss hidden or very small leaks, whereas a leak-rate limit gives a clear, objective pass/fail criterion.