Validation Testing of Safety-critical Software

A software engineering process has been developed for the design of safety critical software for Wolsong 2/3/4 project to satisfy the requirement of the regulatory body. Among the process, this paper described the detail process of validation testing peformed to ensure that the software with its hardware, developed by the design group, satisfies the requirements of the functional specification prepared by the independent functional group. To perform the test, test facility and test software ore developed and actual safety system computer was connected. Three kinds of test cases, i.e., functional test performance test and self-check test were programmed and run to verify each functional specifications. Test failures ore fedback to the design group to revise the software and test result were analyzed and documented in the report to submit to the regulatory body. The test methodology and procedure were very efficient and satisfactory to perform the systematic and automatic test. The test results were also acceptable and successful to verify the software acts as specified in the program functional specification. This methodology can be applied to the validation of other safety-critical software.