Patent ID: 8291903

Claim:
A water trap for use with a breathing apparatus and connected to a gas measuring device, the water trap comprising: a gas inlet; a connection line; a first water separation membrane, said gas inlet leading to said first water separation membrane via said connection line; a water tank, said connection line leading from said first water separation membrane into said water tank on an incoming flow side of said water separation membrane, and leading to the gas measuring device on an outflow side of said water separation membrane and with a vacuum of the gas measuring device applied thereto; a gas-permeable membrane, said water tank having a rinsing gas flow line arranged above a liquid level and leading upward via said gas-permeable membrane to the gas measuring device and with the vacuum of the gas measuring device applied thereto; a water transport line associated with said water tank and extending below the liquid level of said water tank for the emptying said water tank; one of a nonreturn valve with downstream liquid pump for providing a downstream suction in said water transport line and a solenoid valve with downstream vacuum in said water transport line; a control and analyzing unit; and a filling level detection system connected to said control and analyzing unit, said control and analyzing unit being connected to said liquid pump or to said solenoid valve so that said water tank can be emptied as a function of a signal of said filling level detection system, said filling level detection system including an RFID tag and a detector unit arranged on diametrically opposite sides of said water tank, said detector unit transmitting a signal through said water tank to said RFID tag, and receiving a signal from said RFID tag through said water tank, said filling level detection system detecting a change in a liquid level in said water tank based on the received signal.