Except as regards Class 7 (radioactive) materials, nothing contained in parts 170-189 of this subchapter shall be so construed as to nullify or supersede regulations established and published under authority of State statute or municipal ordinance regarding the kind, character, or quantity of any hazardous material permitted by such regulations to be transported through any urban vehicular tunnel used for mass transportation.

[Amdt. 177-52, 46 FR 5316, Jan. 19, 1981, as amended by Amdt. 177-78, 55 FR 52710, Dec. 21, 1990; 62 FR 51561, Oct. 1, 1997]