The artificial nuclide big surface source standard which is used for calibration of airborne or carborne gamma-ray spectrometer for gamma-ray radiation environmental monitoring in the nuclear emergency is a new one of metrological guarantee which has been established by Airborne Survey and Remote Sensing Center of Nuclear Industry over ten years.Using the big surface source standard,we may effectively make up the weakness hard to be simulated and computed due to the complicated factor of the angular respons...