"The expensive full-body scanner is not a must in China. Airports could enhance the sensitiveness of the metal scanners, giving every passenger a pat-down to prevent incidents like the foiled Christmas Day attack," he said.

The CAAC has not come to the final decision, but Li said security checks at major airports have been strengthened to the level of the 2008 Beijing Olympic Games.

Nine security measures have been added, including deploying more air police in plain clothes onboard airplanes and giving more hand checks on luggage.

A second security check is also arranged for passengers boarding high-risk flights, especially flights to the United States, he said.

But airplane passengers said the tightened security checks resulted in a longer time to board flights, and a quickened security check process is preferred, even if it means that privacy might be exposed.

Shi Rui, a doctoral student at the University of Pennsylvania, who flew from Shanghai with a US Northwest Airlines flight on Jan 10, said she was surprised by the unexpected long queue in front of the boarding gate and was a little annoyed by the long wait.

"The second checkup was in the passenger loading bridge. We thought the bridge was empty, but then, after a turn, suddenly we saw the long queue," she said.

Two officers were giving passengers a pat-down, while four others, standing behind steel tables, searched every bag.

"You can also expect an additional check near the luggage check-in counter, where airport staff randomly scoured through passengers' luggage before they are checked in," she said.

"It is the same measure adopted in the summer of 2008."

Cheng Yuan, another Chinese student who flew from Beijing to the US on Jan 13 with United Airlines, also went through the same security procedure at the Beijing Capital International Airport.

"I am accustomed to the complicated security checks (at airports)," he said.

"But airports should do their job to streamline the process and use necessary high-tech facilities, which can save time and trouble while making flights safer.

"The full-body scanner is acceptable... Exposing one's body to only a couple of security officers is nothing," he said.