What span of control necessitates the inclusion of an ISO by the Incident Commander?

The inclusion of an Incident Safety Officer (ISO) by the Incident Commander is primarily influenced by the span of control, which refers to the number of individuals that one supervisor can effectively manage at any given time. The optimal span of control, especially in emergency management and incident response, is typically considered to be between three and seven personnel, with a common standard being around five.

When the span of control rises to the point where it surpasses this effective range, particularly reaching five or more, the complexities of managing personnel and ensuring safety increase significantly. An ISO acts as a dedicated resource to focus solely on the safety considerations of the incident. When the incident command structure appears to exceed a span of control of four, the addition of an ISO becomes particularly critical. This ensures that safety issues do not get overshadowed by operational demands, providing a focused approach to manage the specific safety concerns that arise.

In summary, the identification of a span of control of four necessitates the presence of an ISO to help maintain safety oversight and support the Incident Commander in effectively managing the incident while safeguarding personnel involved.