An apparatus includes a flexible elongate member that defines a lumen and is configured to be inserted within a body passageway of a patient. The air pollution control apparatus includes an economizer bypassing unit 15a that diverts high-temperature combustion gas 11 to a downstream side while bypassing an economizer 15 provided in a gas flue 10a for combustion gas 11 from the boiler, provided with an ammonium-chloride supply unit 101 that supplies powdery ammonium chloride to the economizer bypassing unit 15a. The performance profile associated with each of the hard disks is stored at a location on the hard disk.