THE RAILWAYS ACT, 1989 – Chapter XV – Section 167

167. Smoking
(1) No person in any compartment of a train shall, if objected to by any other passenger in that compartment, smoke therein.
(2) Notwithstanding anything contained in sub-section (1), a railway administration may prohibit smoking in any train or part of a train.
(3) Whosoever contravenes the provisions of sub-section (1) or sub-section (2) shall be punishable with fine which may extend to one hundred rupees.

Forward reference⇒ Section 168