Patent ID: 7665673

Claim:
A method of spraying an air-improving substance into an interrogation area, comprising: defining a predetermined initial point in time when a spray operation is to be performed, the spray operation including spraying the air-improving substance into the interrogation area; defining an ultimate point in time, the ultimate point in time being a predetermined fixed amount of delay time after the initial point in time; detecting whether there is movement in the interrogation area at the initial point in time; performing the spray operation of the air-improving substance into the interrogation area at the initial point in time if no movement is detected in the interrogation area at the initial point in time during said detecting; delaying the spray operation of the air-improving substance into the interrogation area if movement is detected at the initial point in time during said detecting, said delaying being performed up to the ultimate point in time during periods of continuous movement in the interrogation area; performing the spray operation if movement is no longer detected in the interrogation area after the spray operation has been delayed at the initial point in time and prior to the ultimate point in time; and performing the spray operation at the ultimate point in time even if movement is still detected in the interrogation area.