[Problem] A long period of time is necessary to reduce the concentration of chlorine dioxide gas that is used to clean the surrounding environment to a level that is safe for humans. [Solution] A chlorine dioxide gas treatment structure (20) that reduces the chlorine dioxide gas within air to be treated that contains chlorine dioxide gas, and that is provided with: a space in which the air to be treated is circulated a fan (23) a contact layer and an ultraviolet light irradiation means. The contact layer comprises steel wool (21) that is moistened with water and in which fine iron wires are gathered together in a cotton-like state. The fan (23) causes the air to be treated to circulate within the space, and the air to be treated is brought into contact with the contact layer in a state in which the contact layer is irradiated with ultraviolet light by the ultraviolet light irradiation means (24) in the circulation path.本發明提供一種降低包含二氧化氯氣體之被處理空氣中的二氧化氯氣體之二氧化氯氣體處理結構20,其係具備讓被處理空氣循環之空間、風扇23、接觸層、及紫外線照射元件,其中接觸層係將由鐵製細絲固定成綿狀而成之鋼絲絨21被水潤濕而成,風扇23讓被處理空氣於空間內循環,在該循環路徑中以紫外線照射元件24將紫外線照射至接觸層之狀態下,讓被處理空氣與接觸層接觸。100‧‧‧二氧化氯氣體處理裝置10‧‧‧第1次處理元件20‧‧‧二氧化氯氣體處理結構30‧‧‧導入空氣40‧‧‧中間處理空氣50‧‧‧排放空氣11‧‧‧活性碳過濾器12‧‧‧容器13‧‧‧風扇14‧‧‧箭頭15‧‧‧偵測吸引口16‧‧‧二氧化氯氣體用偵測管21‧‧‧鋼絲絨22‧‧‧容器23‧‧‧風扇24‧‧‧紫外線照射元件25‧‧‧箭頭26‧‧‧貯水盤27‧‧‧濃度偵測位置28‧‧‧鋁箔
