International travellers leaving from Wellington and Christchurch airports can expect a smoother time through security with the introduction of new scanning technology.

The Civil Aviation Authority said the new technology would significantly improve aviation security operations.

The new Computed Tomography scanning machines remove the need for physical bag searches in most cases.

The CAA said they also meant electronics such as laptops and tablets, and liquids, aerosols and gels could stay in passengers' carry on bags when they went through security.

The new machines have been introduced in Wellington and Christchurch, and are expected in Auckland later this month.

Group operations manager Karen Urwin said the new technology meant there was no need for passengers to struggle with unpacking at security screening.

But those travelling with camera film would need to make sure it went in their checked in luggage to avoid any damage to it.

"We acknowledge this might present an inconvenience to those passengers, but security is our primary focus," Urwin said.

"The last thing we want is for someone's wedding memories or holiday snaps to be destroyed going through screening, so please put your film in your checked luggage."