How long should a pressure test for LNG/LHG transfer systems be held?

The accepted duration for holding a pressure test for Liquefied Natural Gas (LNG) and Liquefied Hydrocarbon Gas (LHG) transfer systems is typically 30 minutes. This duration is standardized to ensure that any leaks or system weaknesses can be reliably detected within a reasonable timeframe.

A pressure test lasting for 30 minutes establishes a balance between thoroughness and practicality. During this period, the system is monitored for pressure changes which could indicate leaks. If pressure drops, it signals a possible defect or leak in the system components. A test of this length allows operators sufficient time to evaluate the integrity of the transfer system without being overly time-consuming, thereby ensuring that safety and operational efficiency are maintained.

While longer durations like 1 hour or 2 hours may provide additional confidence in system integrity, they are generally not required by the established guidelines for these types of systems, making a 30-minute duration an optimal choice for regulatory compliance and safety management during pressure testing.