Airport security staff say they haven't made the call to go on strike lightly.
From July 20, a series of rolling strikes will see security staff at airports in Auckland, Wellington and Christchurch walk off the job for up to three-and-a-half hours at a time. It comes after they failed to agree on a new collective employment contract with the Aviation Security Service.
It's the first industrial action they've taken in 30 years.
"This is a dispute that's been a long time in the making," Public Service Association (PSA) national secretary Glenn Barclay told Paul Henry on Tuesday morning.
"Our members are very committed people, they're very committed to their job and they don't take this kind of action lightly."
He estimates more than 90 percent of airport security staff belong to a union - either the PSA or E tu - so the airports won't be able to cover their positions, potentially leaving travellers stranded during the busy school holiday period.
Mr Barclay denies that was the unions' intention.
"It has the potential to do that, but that's not the purpose for taking the [action] now. We're doing it because we've just reached the point where we can't progress any further."
Former Aviation Industry Association chief executive Irene King says frustrated passengers will be looking to cancel any flights they've booked on the affected days, and it will cost airlines "dearly".
"I would imagine that they'd be pretty hacked off about it all. The flights cannot fly without this service being there."
The contract offered by Aviation Security Services would see some members go three years without a pay rise. Mr Barclay says that's a "significant wait" and not good enough. He hopes the threat of a strike will bring Aviation Security Services back to the bargaining table.
"Our members are very fed up. It takes a lot for these skilled and highly trained law enforcement officers to get to this point."
E tu says security staff hope mediation and a "decent pay rise" will render the strikes unnecessary.