IACS UR E22

IACS Unified Requirement E22 governs computer-based systems on board ships: hardware, software, and networks that perform monitoring, control, alarm, or safety functions. First adopted in 2006 and revised since, it sets requirements for system categories by failure consequence, software quality, integration testing, and software maintenance over the system lifecycle. E22 is the configuration-and-software-management baseline; the later UR E26 (cyber resilience of ships) and E27 (cyber resilience of onboard systems and equipment) add the cyber-security layer for ships contracted for construction on or after 1 July 2024.