In many different standards the subject matter of dependability, including reliability, availability, maintainability and safety/security, RAMS(S) for short, is defined by various concepts. Their unambiguous definition can lead to a clear interpretation which facilitates communication of all persons involved in the development of safety-critical railway applications. By means of concise communication during specification, subsequent implementation as well as the preparation of operating and maintenance manuals negative legal and financial impacts can be avoided. This paper introduces a method for terminological disambiguation and applies it to the terms “safety” and “security”.
