Abstract: The Trans-Asia Gas Pipeline consists of lines A, B and C, which are designed and put into operation by stages, so the ESD systems in the stations are different in design concepts and control logics. Such control logics are difficult to be managed, which may trigger false actions. The ESD system in CCS2 station along Line C was analyzed to identify the rationality of control logics. Some modification suggestions were proposed, to unify the standards. It is shown that the ESD system in CCS2 station is classified into four levels, and it is subjected to the problems of over-protection or under-protection. Moreover, its causal logic of interlock protection is inconvenient for management. The new design principles of ESD system were summarized. Firstly, the station-level ESD should be activated in case of fire alarm in compressor plants, or combustible gas leakage or ESD button triggered in process areas. Secondly, the compressor area ESD should be activated once the high-high alarm of outlet temperature or pressure occurs; the generator area ESD should be activated when combustible gas leakage or fire alarm occurs in generator plants. And thirdly, the unit ESD should be activated in case of combustible gas leakage or ESD button triggered in compressor plants. The reclassified 3 grades ESD system guarantees the safe operation of Trans-Asia Gas Pipeline.