Orlando Sentinel / Getty Images A TSA screener pats down a traveler at Orlando International Airport on November 24, 2010.

Airport administrators across the country trying to opt out of using TSA screeners for security checks are required to explain how private screening would be advantageous to the TSA. Only problem is the TSA won’t disclose what that means.

Since 2004, airport authorities have been eligible to apply for the TSA’s Screening Partnership Program, which allows airports to staff checkpoints using private-screening contractors instead of TSA agents, though still working under federal oversight. Currently 16 airports participate in the opt-out program, including San Francisco International Airport, Kansas City International Airport, Greater Rochester International Airport and several regional airports.

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Early this year, with little warning and with applications still pending, TSA administrator John Pistole put the program on hold, saying he did not see the benefits of continuing to allow more airports to hire private contractors to do screening. In March, the TSA released a revised application asking airports to explain how private screening would provide “a clear and substantial advantage to TSA’s security operations.” Applicants are encouraged to attach all supporting documents, but the problem is that they have been given no indication as to what TSA actually means when they ask for such information.

“Is this in terms of cost? Is this in terms of security?” asked Christopher Bidwell, vice president, of security and facilitation for Airports Council International — North America, when contacted by NewsFeed. Bidwell explains that the TSA has not yet provided the criteria that they believe would make private screening a “clear and substantial advantage” to the TSA. “Airports want to know the criteria in advance so that they can include that in their applications,” says Bidwell.

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The TSA has said they will consider the complaints from airport administrators but has not yet released any further information or details explaining the new criteria. The agency has tried to resist turning over airport screening to private contractors, claiming that doing so would be costly and would also put airports and planes in danger. But earlier this month, U.S. Congressman John Mica, of Florida — also the chairman of the House Transportation and Infrastructure Committee and a frequent critic of the Transportation Security Administration — said a four-month study by his staff showed that private screeners are 65% more efficient than government screeners and using them could actually save taxpayers $1 billion over the next five years.