What type of shutoff valve must be installed at the discharge end of the transfer hose?

A quick-acting valve must be installed at the discharge end of the transfer hose to ensure safe and efficient handling of liquefied petroleum gas (LPG). The primary purpose of this valve is to provide a reliable means of quickly shutting off the flow of gas, which is crucial in emergency situations or when immediate action is required to prevent leaks or spills during the transfer process.

Quick-acting valves are designed to operate rapidly, minimizing the risk of combustible gas escaping into the environment. This feature is vital for ensuring user safety and maintaining compliance with NFPA 58 regulations, which emphasize the importance of having effective safety mechanisms in place during LPG handling.

In contrast, a manual valve may not offer the same speed of operation in critical situations, and although a slow-release valve could provide control over the flow, it would not be adequate for immediate shutoff needs. Gravity valves are not suitable in this context, as they do not allow for proactive management of gas flow during transfers. Thus, the quick-acting valve aligns with the NFPA 58 standards for safety and operational effectiveness in LPG transfer operations.