GB/T 28808-2021 Active

1.1 This document specifies the processes and technical requirements for the development of programmable electronic system software used in rail transit control and protection applications. It applies to any field with implied safety. These systems may be implemented using dedicated microprocessors, programmable logic controllers, distributed multiprocessor systems, large-scale centralized processor systems, or other architectures.
1.2 This document only applies to software and the interaction between software and the system in which it resides.
1.3 This document does not apply to software that is deemed to have no impact on safety, i.e., software failure will not affect any identified safety functions. Due to uncertainties in risk assessment and even hazard identification, the concept of SIL0 is introduced. For software components with safety impact lower than SIL1 functions, they must at least meet the SIL0 requirements of this document.
1.4 This document applies to all safety-related software used in rail transit control and protection systems, including:
a) Application design;
b) Operating systems;
c) Support tools;
d) Firmware.
Application design includes high-level programming, low-level programming, and specialized programming (e.g., ladder logic for programmable logic controllers).
1.5 This document also addresses the use of existing software and tools. If such software is to be used, it must meet the specific requirements for existing software in 7.3.4.7 and 6.5.4.16, as well as the requirements for tools in 6.7.
1.6 Software developed according to any version of this document is considered to comply with the provisions of this document and is not subject to the requirements for existing software.
1.7 This document considers the current practice of using general-purpose software based on multiple application scenarios for application design. This general-purpose software, after being configur