PROBLEM TO BE SOLVED: To provide a method of inspecting precisely a pressure loss in a honeycomb structure. SOLUTION: An inspection device 100 inspects the pressure loss in a DPF 10 as follows. A temperature, humidity, and atmospheric pressure in a chamber 110 are measured respectively at first based on a temperature signal from a thermometer 124, a humidity signal from a hygrometer 126, and an atmospheric pressure signal from a barometer 122. Then, a target value of an actual flow rate is set based on the temperature, humidity and atmospheric pressure of gas. The actual flow rate means flow rates of the gas flowing in exhaust pipes 130, 131, 132, 133. The target value is increased or decreased therein followed to an increase or decrease of the actual flow rate in accompaniment to changes of the temperature, humidity, and atmospheric pressure. A control part 180 regulates thereafter a rotation speed of a fan 142 to bring the actual flow rate into the target value. The pressure loss of the gas due to the DPF 10 is measured based on a pressure loss signal from a differential pressure gage 120, when the actual flow rate is brought into the target value. COPYRIGHT: (C)2008,JPO&INPIT
