A pneumatic assembly for a pressure decay tester of printhead integrated circuits includes a pressurized air supply. A pneumatic clamping arrangement is in fluid communication with the pressurized air supply for clamping a carrier for the printhead integrated circuits such that the carrier is in fluid communication with the printhead integrated circuits. A valve arrangement applies a predetermined pressure to the carrier. A sensing arrangement senses a static pressure in the carrier. A control system is in communication with the clamping, valve and sensing arrangements to control operation thereof and to generate a discernible signal representing said static pressure such that a decay in said static pressure can be determined.