What is a key consideration when sizing pressure relief devices?

When sizing pressure relief devices, one key consideration is the expected system peak pressure. This is crucial because pressure relief devices are designed to protect systems from over-pressurization by venting excess pressure when it exceeds a predetermined limit. If the device is not sized correctly to accommodate the peak pressure that the system may reach under normal operating conditions or during upsets, it may fail to operate effectively. This could lead to catastrophic failure of the system or potential safety hazards.

Ambient temperature variations, unit cost of the device, and frequency of maintenance are also important factors in system design and operation, but they do not directly impact the sizing of the pressure relief device in the same fundamental manner as the expected system peak pressure. Ultimately, ensuring that the relief device can handle the maximum expected pressure is essential for maintaining system integrity and safety.