Airline passengers will face a double-screening process, according to the head of the airline industry's largest trade group said. The extra screening step is designed to keep passengers from carrying aboard any liquids that might be fashioned into explosive devices once airborne.

Passengers and their carry-on luggage will be checked not only at the main security checkpoint, but also a second time at the boarding gate. The stepped-up screening began Thursday at 25 airports with flights bound for Britain.

``It's going to spread across the whole system tomorrow,'' said James May, president of the Air Transport Association.

"We think we will be at this for 3 or 4 days," Ben DeCosta, General Manager of Hartsfield-Jackson told WSB.

Thanks to beefed-up airport security, frequent business fliers may not be flying as frequently in the future. In addition to long security lines, business travelers face the prospect of having to check their laptops computers and other carry-on gadgets deemed essential.