In energy and cybersecurity: programmable systems or devices that interact with the physical environment (or manage devices that interact with the physical environment). These systems/devices detect or cause a direct change through the monitoring and/or control of devices, processes, and events. Examples include industry control systems (ICS), building management systems, fire control systems, and physical access control mechanisms (NIST SP 800-37 Rev. 2) [Section 3(v), DOE Department Circular No. DC2025-01-001, Institutionalizing the Energy Sector Cybersecurity and Cyber Resilience Framework]
