The Transportation Security Administration and Continental Airlines have expanded their Mobile Boarding Pass pilot program to San Diego International Airport.

The program lets passengers receive boarding passes electronically on their mobile phones or PDAs. The handsets are then scanned by TSA security officers at the checkpoint and eliminate the need for a paper boarding pass.

"For Continental our strategy was to provide our customers an extra convenience and benefit," said Mary Clark, spokeswoman at Continental, Houston. "Our customers have told us that they want to be able to use their own technology when travelling and we want to provide them with convenience wherever they are."

The deployment of the paperless technology signifies TSA's commitment to develop and implement new technologies while at the same time enhance security.

Each paperless boarding pass will display a two-dimensional bar code along with passenger and flight information that will identify the traveler.

TSA travel document checkers will use scanners to validate the authenticity of the paperless boarding pass sent to Continental passengers.

The new technology heightens the ability to detect fraudulent boarding passes while improving customer service and reducing paper use.

TSA created the concept of how to scan the paperless boarding passes and Continental developed an implementation plan that involved encrypting the paperless boarding pass to ensure authenticity.

Continental was the first U.S. airline to test paperless boarding passes and now offers the service at 18 airports.

The TSA paperless boarding pass pilot is currently operating at 22 airports including San Diego.

The pilot is consistent with the global standard of the International Air Transport Association for bar coding of passenger boarding passes. TSA will continue to expand the use of electronic boarding pass scanners at the pace of participating airlines.

"A lot of customers use a mobile device for all of their business and this is just an extension of that," Ms. Clark said. "The mobile boarding passes are beneficial for travelers who are away from the home or office and may not have access to a computer.

"Mobile boarding passes also use less paper and is part of our environmental initiatives," she said.