When Sydney Airport closes for business tonight another group of workers will fire up.

Major construction work to upgrade airport security is now under way.

It’s a 24/7 job that officials promise will one day bring an end to check-in pain.

Terminal two at Sydney Airport holds the title of the busiest terminal in Australia. After remaining unchanged for 30 years, a $200 million redevelopment project has commenced.

This significant upgrade includes implementing government-required updates to a terminal originally designed to serve only 8 million passengers annually back in the era of Ansett.

New lanes will be added, along with advanced CT technology for scanning bags. This advancement means that passengers will no longer need to remove laptops and electronics from their bags for screening.

On completion, the airport promises passengers will move from curb to gate in just 15 minutes

The priority is keeping things moving to ultimately double domestic capacity.

The works have been planned to minimise disruption.

All the major makeover is happening behind closed doors, so 17 million passengers can continue to travel through each year

As the work progresses across the terminal there’ll be 55 new check-in desks, all self-serve.

The international terminal will also get revamped space for boarding airside buses as well as upgraded lounge areas.

Sydney Airport says it’s investing about $2 million a day, with work on the first stage of T2 to continue until the end of the year.