The ATM420 is a touchscreen display that is designed as audiovisual room pressure monitoring in clean rooms, operating rooms or isolation rooms. The display provides visual monitoring that functions as a traffic light. If the pressure difference is correct, the entire display will turn green and outside the desired values the display will turn red. In addition, the display has a built-in acoustic alarm with adjustable delay and acceptance function. The ATM420 can monitor one or two separate pressure differences, so that an air lock and a clean room can be monitored simultaneously with one display. The alarm can be deactivated for cleaning or maintenance, for example.