Abstract: An arrangement and a process filter out at least one gas from a gas mixture. A filter unit (4) of the filter arrangement comprises an inlet and an outlet and is adapted to filter the gas out of the gas mixture while the gas mixture flows through the filter unit (4). The filter unit (4) takes up the gas and heats up in the process. A filter temperature sensor (46, 46.2) of the filter arrangement is adapted to measure at least once an indicator of the temperature in a first measuring area (MP, MP.2) inside the filter unit (4). Depending on the measured temperature, a message is generated and output in a form perceptible by a human being. This message includes information about the current state of the filter unit (4).