With similar benefits to conventional fieldbus technology, safety-related fieldbus has fundamentally changed safety control systems used in manufacturing operations. The introduction of new standards and revision of others have allowed safety-related systems to utilise "state of the art" electronic, programmable, and network based technologies. Developments in safety-related fieldbus are transforming the way safety is being engineered in the plant. The requirements of reliability, flexibility and comprehensive diagnostics can no longer be met with conventional relay based systems. The development of safety-related networks not only fulfils these essential needs, it is supporting new functionality and meeting the requirements of future safety systems.