The BI Valves work like a faucet, they are connected to the output of medical stations (removing the conventional output with gas connector and impact pin). When the accessory is connected, the valve (the BI Valve) is opened and, when the accessory is disconnected, the valve (the BI Valve) is closed. They have different colors for each gas as well as output connectors according to ABNT 12,188 standards.