A non-passenger automobile means an automobile that is not a passenger automobile or a work truck and includes vehicles described in paragraphs (a) and (b) of this section:
49 C.F.R. §523.5
Sec. 9, Pub. L. 89-670, 80 Stat. 981 ( 49 U.S.C. 1657 ); sec. 301, Pub. L. 94-163, 89 Stat. 901 ( 15 U.S.C. 2002 ); delegation of authority at 41 FR 25015, June 22, 1976.