Under what condition does the excess flow check valve activate?

The excess flow check valve is designed to activate in specific situations to prevent the hazards associated with high flow rates of gas. It primarily comes into play when there is a significant disruption in the system, such as when the container falls and the regulator is damaged. In this scenario, the flow of gas could exceed safe levels, leading to potential hazards like leaks or explosions. The valve restricts the flow, thereby preventing an unsafe situation from developing.

In contrast, the activation of this valve is not linked to conditions like the container being too full or an excessive rise in temperature. While both of these situations pose risks, they do not directly trigger the excess flow check valve. Furthermore, the valve's purpose is not activated solely by high supply levels; it specifically responds to circumstances that would allow for an uncontrolled flow, making the condition of damaged equipment the key factor for activation.