The device comprises an assembly intended to be mounted on a closure valve of a high pressure container and comprises a manual control device operating a distribution valve in which the upstream end communicates with the closure valve, a pressure reducer and a safety device against over pressures between the distribution valve and an outlet for connection to a user circuit, as well as a manometer which measures the pressure upstream of the distribution valve. A pusher-rod operates the valve of the closure valve in response to a movement of the distribution valve.