Persons working on highways. Unless specifically made applicable, the provisions of this part, except those contained

§ 3104.  Persons working on highways. Unless specifically made applicable, the provisions of this part, except those contained in Subchapter B of Chapter 37 (relating to serious traffic offenses), shall not apply to persons, motor vehicles, and equipment while actually engaged in work upon a highway but shall apply to such persons and vehicles when traveling to or from such work.