Application: HV test shielding room  (faraday cage) are Widely used in power cable, transformer, transformer switch, transformer substation and other High voltage levels of partial discharge test or impulse test. For HV testing shielding room, as a HV test place, it should has good electromagnetic shielding condition. And its electromagnetic compatibility always is of great importance. Firstly, it should restrict electromagnetic wave into inside shielding room caused by discharge when making HV test to weakening interfere to outside, especially on electronic and communication system. Secondly, it should prevent outer electromagnetic wave intruding into shielding room to cause measurement error of partial discharge and wireless. Thirdly, it should reduces open circuit voltage and closed current to restrain common-mode interference so that to avoid equipment damage and to improve accuracy of impulse measurement. For  GIS HV test shielding room, design area is 500 m2ï¼?Length 25mã??Width 20m). From provided information , we find that steel structure have been completed already with one set of 20T crane indoor, crane supporting corbel also completed, the height is 17.9m from ground to upper part of corbel. Main door height 13m,width 10m, locates at downward of the west side, the door open direction towards to north . According to ILJIN drawing, three side of structure column has already, but western structure column still missing yet. however, as the main door will be located in this side, the western side also should have steel structure , and this structure position still should be unified considered with main door installation. We will be able to submit suggested design diagram with position & size of this structure column for reference. in order to save  construction cost, the construction engineering will be carried out by ILJIN team.