What type of valve should be installed in sections of piping where liquid LP-Gas can be isolated?

In the context of isolating liquid LP-Gas within a piping system, the most appropriate choice is a hydrostatic relief valve. This type of valve is specifically designed to release pressure from the system if it rises above a predetermined level due to thermal expansion or other factors. It helps to protect the piping and equipment from damage or catastrophic failure by ensuring that excess liquid or vapor does not lead to unsafe pressure conditions.

Hydrostatic relief valves are commonly used in systems handling volatile substances like propane, as they provide a critical safety function in preventing excess pressure buildup in sections of the piping where liquid propane is present. By venting excess pressure safely, these valves help to ensure the safe operation of the entire gas system and mitigate the risk of leaks or explosions.

Other options, while serving important roles in different scenarios, do not specifically address the need for isolating liquid LP-Gas in the way that a hydrostatic relief valve does.