The battle between Aviation Security and its workers will head to court this week as unions try to stop a lockout.
Aviation Security advised the unions of the lockouts at five international airports after security staff gave notice of strikes later this month.
"It's hugely significant. An eight-day lock out of aviation security staff is an awful long time, so it will have a huge disruptive effect," says Glenn Barclay of the Public Service Association (PSA) union.
Mr Barclay says the lockout is unlawful and irresponsible.
He's also critical of suggestions Defence Force staff could be brought in to fill the security roles.
"Our people are well trained, they understand how to use the equipment, they know what they're looking for and how to look for it, and their roles are being taken over by someone else who doesn't understand all that stuff and I think that will increase the security risk."
The PSA hopes the matter can be resolved during mediation.