The challenge that is dealt with is to purify air in a closed area. The goal is achieved by making electrolysis to water to generate oxygen and hydrogen. Thus, oxygen can be used in breathing in a closed area and hydrogen is let to dissolve in air. The problem that was faced is that people exhale and let out carbon dioxide. This problem is solved by materials that can remove CO2. The idea is to install membranes that reserve CO2 and then be compressed for storage which is can be used as organic compounds. By these processes, goal is achieved.