Continental Airlines in the US is testing a controversial self-boarding method.

The experiment, taking place at George Bush Intercontinental Airport, allows a passenger to swipe a boarding pass at a kiosk, thus opening a door that gives the traveller access to the plane.

The Transportation Security Administration has already determined the method does not impact on the security of the travelling public, as all passengers would be screened first at security checkpoints.

But some overseas airline companies have expressed concern over the idea, suggesting that as the United States is the biggest target for terrorist organisations, it should not have self-boarding.

The Continental self-boarding trial follows recent technological developments, which already allow passengers with smart phones to check in using unprinted boarding passes.