What is required to shut down in the event of system actuation?

The requirement to shut down all vehicle fuel dispensers simultaneously in the event of system actuation is based on safety protocols intended to prevent potential fire hazards and ensure a comprehensive response to a fire or hazard situation. When a dry chemical extinguishing system is activated, it indicates that a fire has been detected, and any ongoing fuel dispensing could exacerbate the situation by providing more fuel to the fire or creating additional risks for personnel and property.

Shutting down all vehicle fuel dispensers at once helps mitigate these risks by preventing any possibility of fuel being dispensed during an emergency. This coordinated approach also aligns with the overarching safety goals of the NFPA standards, which emphasize a comprehensive approach to fire safety measures.

Moreover, while isolating a single dispenser might seem adequate, it leaves open the possibility of an ongoing hazard at other dispensers. By ensuring that all dispensers are shut down, the system aims to eliminate any risk of ignition and protect responders, bystanders, and the surrounding environment.