Abstract: A leak detection system capable of efficiently dry-testing containers such as steel drums of large capacity. The system includes a test station constituted by a hermetically-sealed chamber adapted to receive a container to be tested and provided with a retractable head coupled to an external fill assembly. The head functions to sealably engage the bung hole or other container opening and to fill the container with pressurized air, the pressure within the container being maintained during the test period at a constant level, whereby physical distortion of the container is controlled. The pressure within the test chamber is sensed and the output of the sensor is applied to a data processor wherein the influence of temperature on the test chamber pressure is discounted by means of a waveform scanning technique, making it possible to determine the extent to which the container under test is heated and to predict the error pressure in the chamber due to thermal effects.