RAMS is an abbreviation for the term packet "Reliability, Availability, Maintainability and Safety " ( in English: Reliability, Availability, Maintainability, Safety - hence the acronym ). This definition can be found in the CENELEC standard EN 50126, which is published as DIN standard. The standard EN 50126 is constantly expanded and modified by the European Committee for Electrotechnical Standardization, CENELEC (Comité Européen de Normalisation for Electrotechnical Standardization ). RAMSS also includes "Security", the protection of the system against external attacks.

The relationship of these terms RAMS wins today in all industries with high investment risk and potential of increasing importance. It is particularly used in the railway industry for the system specification of security systems in the railway sector. The associated management system is often referred to as Integrated Logistics Support ( integrated logistic support ).

RAMS is as defined by EN 50126 a process or methodology that will help to prevent errors during the planning phase of projects. RAMS can be applied to the development and introduction of new products, but also in planning and implementation of new systems. A RAMS management ensures that systems defined, risk analysis (see Probabilistic Safety Analysis ) performed determines hazard rates, made ​​detailed inspections and safety certificates are created.

The objectives of safety and operational availability can be realized only if the reliability and maintainability requirements are constantly met and the ongoing long-term maintenance as well as the business environment to be monitored. The availability ( availability) based on knowledge of the reliability (Reliability ), based on the system failure rates (RAM ) analysis, the analysis of possible hazards (Hazard and Operability Study ), the probability of the occurrence of a failure ( fault tree analysis), the effect of a failure on the functionality of a system (FMEA (CA ) ) and on knowledge of maintainability ( maintainability ), based on knowledge of repair times. The RAMS process is not complete until the product has been taken out of service and disposed of.

For standard two corrections have been published. The amendment 1 changes the title and number of the standard. In Corrigendum 2 of Annex ZZ added by CENELEC.