Often used for Pressure Relief Devices (bedsores or pressure sores).

A pressure relief device is a device designed to prevent pressure or vacuum from exceeding a predetermined value in a pressure vessel by transferring a fluid during emergency or abnormal pressure conditions. However, different definitions exist for specific devices, their testing, and their operating characteristics. In the case of fire, the Pressure Relief Devices does not mandate any specific accumulation, which must be reviewed by the designer of the pressure equipment and engages his/her responsibility. This should not be determined solely by the safety valve characteristics, manufacturer, or user. In the case of multiple valves, each application would need to be reviewed before any commitment.

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