What must be done if an excess flow check valve is not installed by the manufacturer?

If an excess flow check valve is not installed by the manufacturer, the correct action is that it cannot be used for a forklift. This is due to the critical safety function of the excess flow check valve, which is designed to prevent excessive flow in case of a leak in the fuel system. If this valve is absent, it poses a significant risk of fuel leakage, leading to potential hazards such as fire or explosion. Forklifts that operate on liquefied petroleum gas (LPG) or compressed natural gas (CNG) rely on this safety mechanism to ensure proper fuel control and system integrity. Operating a forklift without this essential safety feature is not compliant with safety regulations and standards, making it dangerous to use in any setting.