We present parts of the specification of a program to remote control and monitor different devices, especially valves, in an explosion test environment. The program was developed within an industrial national project called CATC carried out in PTB, the German federal institute of weights and measures. The CATC information system supports various activities of different user groups that are responsible for testing and certifying explosion proof electrical equipment in PTB. Our approach is based on the formal object-oriented specification language Troll. We describe the advantages of the use of the formal method in our project.