The FTPC gas system was designed by M. Bosteels at CERN (ftpcgassystem_1, ftpcgassystem_2, ftpcgassystem_3). The input gases (normally argon and carbondioxide, alternately nitrogen for flushing) are mixed and led into the FTPCs. Alternately, the gas can be led through a Krypton collector before entering the chambers to add radioactive 83Kr for calibration purposes. The FTPCs themselves have double Mylar windows, using the outflowing gas to flush the space between the two windows. To monitor the quality of the gas in the chambers, the exhaust gas is run through drift velocity monitors as well as water and oxygen sensors. Currently, the plan is to release the gas at this point. However, it can also be run through oxygen and water absorbers and recycled into the chambers.
