ESF 4 provides local support for the detection and suppression of fires resulting from, or occurring coincidentally with, an incident requiring a coordinated response for assistance. It manages and coordinates firefighting activities, including the detection and suppression of fires and provides personnel, equipment and supplies in support of local agencies involved in firefighting operations.

The functions of the Hazardous Materials Emergency Response Team (HMERT) fall under the auspices of the fire service and are more clearly defined in ESF 10 - Oil and Hazardous Material.

Although Search and Rescue functions also fall under the auspices of the fire service, the specific duties of that function are more clearly defined in ESF 9 - Search and Rescue.