The purpose of this research is to detect a person with a sensor network that uses CO2 sensors and to guide a rescue robot to the position at which the person is located. When a person is in a position where sensors are arranged, that person can be detected, but when a person is in a position where sensors are not arranged, detection cannot be performed. Therefore, in this paper, we propose interpolating CO2 concentrations between sensors so that detection of a person can be performed in regions where sensors are not arranged. First, the wind speed required for gas concentration interpolation is estimated from the observed sensor values. Then, the algorithm for interpolating the CO2 concentration between sensors using the estimated wind speed is shown. Finally, the validity of the proposed method is verified by simulation.