Abstract: In order to have a better living environment for the people trapped in refuge chamber and extend their survival time, the variation law of carbon dioxide concentration and air purification problems of refuge chamber were deeply analyzed. Through two groups of real simulations in the experimental chamber, it made comparative experiments with and without air purification system under dry air conditions, and made the data fitting for the trends of carbon dioxide concentration, then obtained that carbon dioxide concentration increased linearly. After the air purification system was enabled, carbon dioxide concentration had been effectively controlled, steady at 0.6%, which provided the basis for survival parameters of refuge chamber, and certified that it was necessary to establish air purification system in refuge chamber.