The Transportation Security Administration plans to begin testing techniques for improving passenger rail security at a station in New Carrollton, Md., that is served by Amtrak and commuter trains that run between Washington, D.C., and Baltimore, according to government officials.

The agency will conduct passenger screening, but not the way it is done at airports. "It is not going to be as invasive as airport screening is," said Dan Stessel, a spokesman for Amtrak. "No one at New Carrollton will be asked to remove their belt or shoes."

The new program, called the "Transit and Rail Inspection Pilot," or TRIP, will begin next month. Its focus is not guns or knives, but bombs, according to officials. Techniques could include bomb-sniffing dogs or electronic detectors, they said.

New Carrollton was chosen because it is convenient to the Department of Homeland Security's Washington headquarters, and because its platforms are elevated in a way that makes it easy to control access, so passengers could be screened before the train arrived.

But that is unusual for both commuter lines and for Amtrak. Amtrak stops in more than 500 places around the United States, and fewer than half are staffed by a ticket agent or any other employee, according to the railroad. The railroad's president, David Gunn, described most of the stops as "platforms in the desert."

As a security precaution, Amtrak stopped selling tickets on board its Northeast Corridor trains, between Washington and Boston, soon after the attacks of Sept. 11, 2001. The change required that a traveler buy a ticket from an agent at a station, which requires showing picture identification, or slide a credit card into a vending machine. The credit card contains information on the identity of the holder, who may or may not be the traveler.

In the Northeast Corridor, passengers are required to show the tickets on boarding, and may be asked to show identification too, although they generally are not.

Outside the Northeast Corridor, passengers can buy tickets after they board, and in most locations, that is the simplest way to get a ticket.

Government security officials say they have discussed whether to compare the names of railroad ticket buyers to "watch lists," as is done with airplane passengers. Stessel said that Amtrak had the capacity to supply such names but had not been asked to do so.