Every container built after December 1, 1965, designed to be filled volumetrically must include a:

A container designed to be filled volumetrically and built after December 1, 1965, must include a fixed liquid level gauge for several important safety and operational reasons. The purpose of a fixed liquid level gauge is to provide an accurate and consistent means to monitor the level of liquid propane within the container. This is crucial for preventing overfilling, which can lead to hazardous situations such as pressure build-up and potential leaks.

Proper monitoring helps ensure that the container is filled to the appropriate level without exceeding its capacity, minimizing the risk of propane escaping from the venting system or other safety measures that could fail. The integration of a fixed liquid level gauge is a regulatory requirement designed to enhance safety practices in the handling and storage of propane.

While other components like manual shut-off valves, pressure relief vents, and liquid level indicators are also important in the safe operation of propane systems, the specific requirement for containers filled volumetrically emphasizes the need for a fixed liquid level gauge as a critical safety feature to ensure the containment and management of propane gas.