EN ISO 24664 : Refrigerating systems and heat pumps - Pressure relief devices and their associated piping - Methods for calculation (ISO 24664:2024).

This document describes the calculation of the mass flow rate required for sizing pressure-relief devices for components of refrigeration systems, as well as the relieving capacities of safety valves and other devices, including the data required for their sizing when discharging to the atmosphere or to components at lower pressure. It also covers the calculation of pressure losses in the piping upstream and downstream of these devices. Finally, it specifies selection requirements intended to prevent overpressure caused by internal or external heat sources, pressure-generating sources such as compressors and heaters, and the thermal expansion of trapped fluid.