N.J. Stat. Ann. § 39:3-54.15

1. A current chief or first assistant chief of a volunteer fire company, or chief officer of a first aid or rescue squad, recognized by and rendering service in any municipality may mount and operate on a motor vehicle owned by him and registered in his name a red emergency warning light or lights, a siren, or both, as prescribed in P.L.1985, c.171 (C.39:3-54.15 et seq.). The size and type of lights and siren, and the location of their controls, shall be determined by the Chief Administrator of the New Jersey Motor Vehicle Commission.