What must any hose installed at LP-gas refueling installations be equipped with?

The correct choice is that any hose installed at LP-gas refueling installations must be equipped with a breakaway device. This device is crucial because it serves to prevent hazardous situations that could arise if the hose becomes disconnected while in use. In the event of a sudden pull or movement that could cause the hose to separate from the dispensing system, the breakaway device allows for a controlled disconnection. This minimizes the risk of spills, leaks, or explosions, thereby enhancing safety for both the operator and the environment.

Other options, while they may have their own functions in different contexts, do not specifically fulfill the safety requirements related to hose safety in LP-gas applications as effectively as a breakaway device does. For instance, a ventilation valve helps manage pressure in certain systems, a filter screen prevents contaminants from entering the system, and a pressure gauge monitors system pressure, but none of these directly address the critical need for safe disconnection in the case of hose integrity being compromised.