Regional Rail passengers won't be allowed to sit in the front two seats of trains made up of the new Silverliner V cars that are starting to be delivered for use, SEPTA officials said Wednesday, citing safety concerns.

Passengers' groups disputed SEPTA's argument, saying the agency was capitulating to rail crews' demands that the front the trains be reserved for their use.

"The concern we had was a combination of safety for our passengers and the safety of our employees operating the trains," said Jim Fox, director of system safety for SEPTA.

While cabs for engineers in the existing fleet stretch all the way across the front of the car, the Silverliner V cabs occupy only half the front end. For several years, engineers have urged SEPTA to do away with the front two seats to give them the same room and view that they have now and to prevent passengers from interfering with the trains' operation.

Passengers' groups have argued that they deserve all the seats they can get and that crew members are more interested in protecting their ability to socialize in the cab.

Fox said engineers needed a clear path out of the cab to "bail out" if a collision appeared imminent. He said passengers or their luggage might block an engineer's ability to get out of the cab quickly in an emergency.

And he said customers in the front two seats would be most vulnerable to injury in a grade-crossing collision or to objects thrown from overpasses.

SEPTA trains cross roads about 4,700 times a day, Fox said. He said there had been about 25 grade-crossing collisions or incidents in the last seven years.

Matt Mitchell of the Delaware Valley Association of Rail Passengers said that "we are not aware of any other railroad in the country with this kind of 'no-go' configuration."

"If the question is egress for the engineer, why has it not been an issue up until now? We have crowded trains every day, and the area by the cab is a common place for people to stand," Mitchell said. "If there really is a safety concern, it's puzzling that it hasn't been made an issue until now."

SEPTA has ordered 120 of the Silverliner V cars, which it hopes to have in service by the middle of next year. The first five cars are operating as a single train.

The front two seats in new Silverliners that are not leading a train will be available for passengers, Fox said.

The exact number of seats that will be lost to passengers is not certain, since it will depend on how many Silverliner V cars are coupled together in trains of differing lengths. During the evening rush hour, for example, SEPTA operates 61 trains, spokeswoman Jerri Williams said, meaning a maximum of 122 lost seats if all the trains were made up of the new Silverliners, which will not be the case. Those trains carry 44,450 passengers a day, spokesman Richard Maloney said.

"The safety gains make the loss of those seats absolutely insignificant," Maloney said.

A riders' group, the Pennsylvania Transit Expansion Coalition, said the smaller-cab configuration had worked in other cities and had been approved by the Federal Railroad Administration.

"Had SEPTA heeded the advice of the public and its employees, taxpayers would not be on the hook" for seats that can't be used for revenue service, the group said in a statement.

Mitchell said, "We're willing to listen if there is a genuine safety reason, but I think this is a pretense for defusing the conflict with the engineers and saying, 'We'll just sell out the passengers.' "

Contact staff writer Paul Nussbaum at 215-854-4587 or