Plenty of smokers blew off the smoking ban on outdoor commuter-rail platforms yesterday, the first day the MTA was supposed to enforce the new state law.

The MTA confirmed it cited no smokers yesterday.

The smoking ban on LIRR and Metro-North outdoor facilities became law in November, but came with a three-month grace period.

Offenders are subject to a maximum $50 fine or a possible 30-day jail sentence.