A test program that allows air travelers who voluntarily offer background information to zip through faster security lines without removing shoes, belts and coats will be expanded to 28 more airports, including those at Seattle-Tacoma, Portland and Anchorage, Transportation Security Administration officials said Wednesday.

The PreCheck program has been tested for several months at seven airports — Atlanta, Dallas, Detroit, Miami, Las Vegas, Los Angeles and Minneapolis — and has been used to screen 336,000 passengers. Eligible travelers now include American Airlines and Delta Air Lines frequent fliers, as well as travelers in three other trusted-traveler programs run by Customs and Border Protection, which, unlike the Transportation Security Administration (TSA), charges a fee to participate.

In addition to the 28 new airports, TSA announced its program will be expanded this year to Alaska Airlines, US Airways and United Airlines.

PreCheck is the Obama administration's first attempt at a passenger-screening program amid frequent complaints that the government doesn't use common sense by screening all passengers in the same way.

"We are pleased to expand this important effort, in collaboration with our airline and airport partners, as we move away from a one-size-fits-all approach to a more intelligence-driven, risk-based transportation-security system," TSA Administrator John Pistole said.

Besides cutting time and hassles for frequent travelers, the expansion is expected to speed screenings in normal passenger lines, said Jeffrey Sural, a former TSA assistant administrator.

"This is the beginning of a wholesale change to the screening experience," said Sural, now a lawyer and public-policy adviser at Alston & Bird LLP in Washington, D.C.

The program works this way: Travelers must go to a TSA website, submit background information and receive an identification number. When booking a ticket online with participating airlines, a traveler types that number into a box. There is no fee.

Travelers aren't told if they have been approved. TSA officers at participating airports scan the traveler's boarding pass. If an embedded code in the pass indicates the passenger has been approved for the program, he or she is directed to the faster security line and likely is allowed to keep on belts, shoes and jackets and leave laptops and liquids in bags during screening.

TSA spokeswoman Lorie Dankers said the agency will roll out the program at Seattle-Tacoma International Airport this year, but has not set a date. She also said the agency has authorized Alaska Airlines to email members of its frequent-flier program and invite them to opt in.

Neither the airline nor Dankers would say how many Alaska customers might qualify or what the criteria for approval is. Dankers said the TSA mainly, but not always, selects the "most frequent fliers."

Sea-Tac spokesman Perry Cooper said TSA has not said when or where the lane might be installed in the airport.

Pistole has said he hopes to test the program eventually at all airports and airlines but that might take years.

Seattle Times travel writer Carol Pucci contributed to this report. Information from the Los Angeles Times, The Associated Press and Bloomberg News also is included.