Which agency's operations require incident command system (ICS) training?

The National Incident Management System (NIMS) is a comprehensive, nationwide template that guides all levels of government, the private sector, and non-governmental organizations in their response to incidents. NIMS incorporates the Incident Command System (ICS) as a key component, which provides a standardized approach to command, control, and coordination of emergency response across different agencies and jurisdictions.

Training in ICS is essential for organizations involved in emergency management to ensure they can effectively respond to incidents. This standardized system facilitates coordinated response efforts, allowing for clearer communication and collaboration among various agencies and responders. As NIMS is foundational to the United States' emergency response structure, those operations that fall under its purview—such as local, state, and federal emergency response agencies—are required to complete ICS training to adhere to NIMS guidelines.

While agencies like the CDC and WHO may engage in public health emergency responses, they do not solely govern the use of incident command systems. FEMA, for instance, implements NIMS and involves ICS training but is one of the entities influenced by NIMS rather than representing a system itself. Hence, NIMS is the correct answer.