(a) The operator of each commercial motor vehicle transporting passengers, service bus or motor vehicle used for the transportation of school children and the operator of each commercial motor vehicle with a cargo tank or carrying hazardous materials, as defined in § 14-1, whether loaded or empty, before crossing at grade any track or tracks of a railroad, shall stop such vehicle not less than fifteen feet or more than fifty feet from the nearest rail of such track, and, while so stopped, shall listen and look in each direction along such track or tracks for approaching locomotives or trains before crossing such track or tracks; and such operator shall not, in any event, cross such track or tracks when warned by automatic signal, crossing gates, flagman, law enforcement officer or otherwise of the approach of a railroad locomotive or train.

(b) The operator of any commercial motor vehicle shall not attempt to cross a railroad grade crossing if such vehicle cannot be driven completely through such crossing, without shifting gears, on account of insufficient undercarriage clearance.

(c) The operator of any commercial motor vehicle shall not attempt to cross a railroad grade crossing if such vehicle does not have sufficient space to drive completely through such crossing and to clear the tracks without stopping.

(d) The commissioner may adopt regulations, in accordance with the provisions of chapter 54, to implement the provisions of this section, including exemptions for certain crossings and vehicles that are allowed by the provisions of 49 C.F.R. § 392.10.

(e) Any person who violates any provision of subsection (a) of this section shall be fined not less than one hundred fifty dollars or more than two hundred fifty dollars. Violation of any provision of subsection (b) or (c) of this section shall be an infraction.