Device for an inert gas installation on a floating vessel

A method for automatic shutdown of an inert gas installation on a floating vessel in connection with marine casualty, wherein the vessel comprises one or several tanks arranged in a manner allowing filling of an explosive liquid and/or a gas therein, wherein an air inlet system and a safety valve are connected to the tank, and wherein the tank is provided with a sensor arranged to respond to a defined, ambient moisture and pressure level, the sensor also being connected to a valve control system, thereby being able to provide control signals to the valve control system, characterized in that the method comprises the following steps:

• the sensor is lowered into water when the vessel is sinking due to marine casualty;
• the sensor generates a predefined control signal which is transmitted to the valve control system;
• the valve control system processes the generated control signal;
• the valve control system causes a control valve, which is associated with a shutoff valve, to close a connection between a pressurized fluid system and the shutoff valve;
• the pressure in a pressurized fluid chamber in the shutoff valve is relieved;
• a biased closing device moves the shutoff valve to a closed position;
• and
• the supply of inert gas to the tank is shut down.