(a) No person shall consume food and/or beverages in any vehicle operated by the NFTA or any subsidiary corporation which is regularly scheduled and operated solely within the NFTA transportation district.

(b) No person while at a transportation facility shall consume food and/or beverages in such areas where appropriate signs have been posted prohibiting such activity.

(c) Proof of consumption of food and/or beverages for medicinal purposes shall be a valid defense to any charge of violation of this section.