N.H. Rev. Stat. Ann. § 21-P:52

There shall be a statewide incident command system based on the incident command system of the National Interagency Incident Management System. The commissioner of safety shall adopt rules pursuant to RSA 541-A to implement the statewide incident command system. The statewide incident command system shall be used in responding to any natural or man-made cause that requires emergency management by multiple agencies or departments within state and local government.