The ban will be enforced by MTA police starting Wednesday morning.
"Anything that helps me quit is good," Bauer, 53, an unemployed technician, said Tuesday at the LIRR station in Mineola. "As you can see, I'm not smoking right now and I want to keep it that way."
Another passenger, William Stetzner, 23, of New Hyde Park, lit up a cigarette as he got off a westbound train. He said he wasn't aware that he'd soon be risking a fine.
"It won't change anything for me," Stetzner, an executive recruiter, said as he stepped into the street. "I only use the train occasionally: to see my girlfriend; to visit the doctor."
The ban took effect in November, but the MTA delayed enforcement as it rewrote its regulations to reflect the ban and conducted a public education campaign.
The MTA said enforcement would begin Wednesday at 12:01 a.m. Smoking inside terminals and on trains has been banned since 1990.
The new ban will be enforced "during regular patrols," with violators facing fines up to $50, the MTA said. The law also carries the possibility of jail time.
One of the law's chief sponsors, state Sen. Charles Fuschillo (R-Merrick), said LIRR patrons have been overwhelmingly supportive. "I'm out at stations a lot and the feedback has been all positive," he said.