What is the span of control under ICS?

In the Incident Command System (ICS), "span of control" refers to the number of subordinates who directly report to a supervisor at any given level of the organization. For example, the Incident Commander (IC) may have three command staff and three general staff reporting to him or her, giving a "span of control" of 6 personnel. Each of those 6 personnel will have their own spans of control, but none of those other personnel directly report to the IC.

The desired range of span of control is 3 to 7 personnel, with 5 being optimal. Under certain conditions, up to 10 personnel may be assigned to one team under a single supervisor.