Amtrak will eliminate smoking next month on some trains and in some stations under new policies that will more strongly segregate nonsmokers and those who want to light up. No-reservation trains of three or fewer cars will be designated no-smoking, Amtrak spokeswoman Sue Martin said Wednesday. ``This will affect a number of trains in the East, some in the Midwest and one in the Northwest,'' she said. ``Seventeen routes will have some trains that at least on some days have no smoking at all.'' Two lawmakers who led the successful fight to ban smoking on most domestic flights said Wednesday that the nation's passenger railroad would adopt the tougher smoking policies April 1. They jumped the gun on Amtrak's own announcement of the new policy, which had been scheduled for today. ``These new rules are another victory for health and common sense,'' said Sen. Frank Lautenberg, D-N.J., chairman of the Senate Appropriations subcommittee on transportation. ``It's further acknowledgement that nonsmokers should not be forced to breathe other people's smoke.'' Lautenberg and Rep. Richard Durbin, D-Ill., a member of the House transportation appropriations panel, had said after the airline smoking ban took effect Feb. 25 that they would turn their attention to railroads. ``It is my hope that eventually nonsmokers will be able to ride smoke-free on all forms of public transportation,'' Durbin said. Although passengers will be permitted to smoke in sleeping compartments and lounges on longer trains, smoking will be eliminated in: _First-class cars on all trains in the Northeast Corridor that don't require reservations. Reserved-seat Metroliners will carry smoking cars and will set aside smoking areas in first-class cars. _All areas except a portion of the lounge on other trains requiring reservations. _Coach cars of reserved-seat, double-deck Superliners operating west of Chicago. Currently, Amtrak allows smoking in the last four rows of Superliner coaches. The new policy will limit Superliner smoking to the lower level of the lounge car, Ms. Martin said. _Stations smaller than 1,100 square feet. _At least three-quarters of the area of larger stations. Amtrak's ultimate goal is to separate the 25 percent of its passengers who smoke from the 75 percent who do not, Ms. Martin said. Toward that end, Amtrak will begin locating its smoking cars at the front or rear of unreserved trains so nonsmokers need not walk through smoking areas to reach their seats. The Amtrak policy changes drew fire from the Tobacco Institute, the lobby for cigarette manufacturers. ``Once again we're seeing unnecessary regulation above and beyond what is necessary,'' said institute spokesman Thomas Lauria. ``Train travelers have accommodated each other, smokers and non-smokers alike, ever since we've had trains,'' Lauria said. ``Obviously this is an attempt to put smokers in the back of the bus once again. On shorter trains, it seems mean-spirited to ban smoking altogether.'' Lauria said he anticipated resistance from smokers to Amtrak's intended smoking restrictions in stations. According to Ms. Martin, the changes are part of the national passenger railroad's fine-tuning of its smoking policy as the number of smokers drops. ``We feel it is very important for our marketing effort to continue to permit smoking on longer trips,'' Ms. Martin said. ``It simply doesn't make good business sense to eliminate smoking altogether.''