What type of protection should be provided to halt the flow of natural gas in the event of a pullaway?

The appropriate type of protection needed to halt the flow of natural gas in the event of a pullaway is breakaway protection. This system is designed to automatically disconnect the fueling system from the vehicle if the connection is unintentionally pulled apart, thereby preventing any accidental release of natural gas.

Breakaway protection allows for safety during the refueling process by ensuring that if there is a sudden movement of the vehicle or the fueling equipment—such as a pullaway scenario—the system will detach without causing damage or leading to hazardous situations. This critical safety measure is specifically tailored for handling high-pressure gas operations and reducing the risk of leaks.

In contrast, safety locks, emergency valve closures, and overflow protections serve different purposes. Safety locks typically secure connections to prevent unauthorized access rather than manage gas flow in emergencies. Emergency valve closure systems can be important but are generally used in contained emergencies rather than specific pullaway incidents. Overflow protection is designed to manage excess liquid and prevents overfilling, and it does not address the potential risks associated with a pullaway situation.

Thus, breakaway protection is specifically aimed at preventing the hazard of gas leaks during disconnections, ensuring safety in scenarios where unexpected movements occur.