The TUV approach to functional safety assessment and certification

The IEC 61508 standard, functional safety of electrical/ electronic/programmable electronic safety related systems, has gained a widespread acceptance and is slowly becoming daily practice in many countries and industries. Since it´s inception in 1998 it has affected end-users and system integrators as well as product manufacturers. For the first time, end-users and system integrators have a standard which is accepted worldwide and guides them throughout the safety life-cycle of their facilities. For product manufacturers the standard gives a guideline for the design of safety equipment. The purpose of this paper is to discuss practical experience with the use of the IEC 61508 standard. Benefits and problems for manufactures, users and certification agencies are discussed in relation to the approval, assessment and certification of safety-related equipment and systems. The paper will address the use of reliability data, the need for measures and techniques for avoidance and control of failures and the positive effects of having functional safety management in place. The paper will also discuss - as an example - the relation with IEC 61511 (specific to the process industry) which is based on IEC 61508