prBAS EN ISO 21789:2025

This document covers the safety requirements for aero derivative and industrial gas turbine prime mover applications using liquid or gaseous fuels and the safety related control and detection systems and essential auxiliaries for all types of open cycles (simple, combined, regenerative, reheat, etc.) used in onshore and offshore applications including floating production platforms. This document applies to mechanical, electrical, and pressure equipment components and systems necessary for the functionality of the prime mover. For example, but not limited to, a core gas turbine auxiliary gearbox, an output transmission gear box, combustion system, air filtration, gas turbine controls, oil systems, and fuel system. This document also covers integration of safety risks within the overall installation, e.g. exhaust purging or drainage. This document details the anticipated significant hazards associated with aero derivative and industrial gas turbine prime movers and specifies the appropriate preventative measures and processes for reduction or elimination of these hazards. This document addresses the risks of injury or death to humans and risks to the environment. Equipment damage without risk to humans or the environment is not covered. The overall objective of this document is to ensure that equipment is designed, constructed, operated and maintained throughout its life in accordance with ISO 12100:2010. This document approaches gas turbine safety from an international perspective based on the content of existing, recognized ISO and IEC standards to the greatest extent possible. Where no ISO or IEC standard exists, other codes or standards (such as EN, NFPA, etc.) have been included. Minimum functional safety levels cannot be addressed in this document, as minimum functional safety levels are both application and site specific. This document excludes the following items; —    exhaust-system structural design; —    driven equipment; —    micro turbines as covered by ISO 19372:2015; —    gas turbines used primarily for direct and indirect propulsion; —    gas turbines used for mobile applications; —    special heat source applications; —    gas turbines in research and development programs; —    compressed-air energy storage plants. Where appropriate, this document can be used to give general guidance in such applications. This document is not applicable to machinery or safety components manufactured before the date of its publication.