What action does the unified command take to determine the scale of an incident?

The process of incident size up is crucial for unified command to assess the scale of an incident effectively. This action involves gathering information about the incident’s scope, nature, and potential impacts. By conducting an incident size up, the command team can identify resource needs, determine the necessary response strategies, and establish the overall incident management framework. This helps in making informed decisions and coordinating efforts among various responding agencies.

In contrast, detailed individual reports provide specific insights but do not offer a holistic view of the incident's scale. Delegating responsibilities focuses more on assigning tasks to personnel rather than assessing the incident itself. Establishing communication protocols ensures that information flows smoothly among teams but does not in itself gauge the size or scale of the incident. Thus, the incident size up stands out as the critical action for defining the incident's severity and response requirements.