Abstract: Fire protection mist nozzles for industrial oil cookers, oil cookers with fire protection systems, and method of oil cooker fire protection are provided. The mist nozzles operate at pressures between 170 and 250 psi, and provide a unique distribution pattern that allows for variable installations for protection in certain operative environments including oil cookers with various hood configurations. The fire protection nozzles includes a base defining an inlet and an outlet along an axis. The base includes an orifice having an inlet diameter and an outlet diameter. The outlet diameter is preferably greater than the inlet diameter; and the orifice defines a K-factor of less than 1.0 gpm/psi½. The nozzle includes a diffuser aligned with the orifice. The diffuser has a preferably substantially domed portion with a maximum diameter that is less than the summation of the inlet diameter and the outlet diameter of the orifice.