PROBLEM TO BE SOLVED: To provide a decomposition/removal method and a decomposition/removal apparatus of a hydrogen peroxide gas, with which the hydrogen peroxide gas in a work environmental chamber is decomposed and removed in a short time and to low concentration.SOLUTION: A hydrogen peroxide gas in a work environmental chamber 10 can be decomposed and removed to low concentration in a short time, because a decomposition/removal method of a hydrogen peroxide gas includes a decomposition/removal step to decompose and remove the hydrogen peroxide gas with a catalyst 13 and a humidification step to humidify the inside of the work environmental chamber 10 to a degree not causing dew condensation, consequently by decomposing and removing the hydrogen peroxide gas with the catalyst 13 in the decomposition/removal step and humidifying the inside of the work environmental chamber 10 to the degree not causing dew condensation in the humidification step, partial pressure of steam is heightened and partial pressure of hydrogen peroxide in the work environmental chamber 10 is made to be in a state of being easily heightened, desorption of hydrogen peroxide adhered to a wall surface and other members in the work environmental chamber 10 is accelerated so as to turn hydrogen peroxide into the hydrogen peroxide gas, and the hydrogen peroxide gas is decomposed and removed with the catalyst in the decomposition removal step.SELECTED DRAWING: Figure 1【課題】作業環境室内の過酸化水素ガスを短時間で低濃度に分解除去できる過酸化水素ガスの分解除去方法および分解除去装置を提供する。【解決手段】過酸化水素ガスを触媒１３によって分解除去する分解除去工程と、作業環境室１０内を結露しない程度に加湿する加湿工程と、を含むので、分解除去工程で過酸化水素ガスを触媒１３によって分解除去するとともに、加湿工程で作業環境室１０内を結露しない程度に加湿することにより、水蒸気分圧を増やし作業環境室１０内の過酸化水素の分圧が増え易い状態として作業環境室１０内の壁面やその他の部材に付着している過酸化水素の離脱を促進して過酸化水素ガスとし、この過酸化水素ガスを分解除去工程で触媒によって分解除去できるので、作業環境室１０内の過酸化水素ガスを短時間で低濃度に分解除去できる。【選択図】図１
