Relieving devices should be located

Relieving devices should be located as close as possible to the exchanger being protected, to limit steady state and transient pressure buildup. Locating a relief valve a significant distance from the exchanger, where the low pressure side is liquid full, could lead to high transient pressure for a long enough period of time to require sizing the relief valve for displaced liquid flow, as indicated in Section 4.7.2. Additionally, the exchanger internal relief path should be considered when determining whether a pressure relief valve, or even a rupture disk, is sufficiently close to the break with adequate response time to open prior to loss of containment, e.g., a tubeside relief device located on one of the two tubeside channels.