Goal setting safety legislation for high pressure systems was first introduced in 1973 and retained in the High Pressure Safety Management Law in Korea. This has enabled a move towards inspection strategies based on the risk of failure. This trend towards a risk based approach is being supported by extensive plant operating experience, improved understanding of material degradation mechanisms, and the availability of fitness-for-service assessment procedures. RBI (Risk-Based Inspection) is very effective and efficient of the inspection and maintenance techniques. In particular, RBI will be found how to apply both inspection interval as a result of RBI implementation and re-inspection interval of pressurized equipment defined by the High Pressure Safety Management Law in Korea. The objectives of this paper are to develop an enhanced KGS-RBITM program to resolve shortcoming inclusive of the above issue and to evaluate the risks of equipments in Naphtha Cracking Center (NCC) which is a typical facility of petrochemical plant using the KGS-RBITM program. The results of the risk assessment and re-inspection interval of internal opening using KGS-RBITM program are useful in determining the inspection planning.