Airport firefighters have voted to take industrial action including work stoppages in the lead-up to the Christmas holiday peak period, claiming staff shortages.
Their employer Airservices Australia, whose management the union members voted "no confidence" in, says the claims are misleading and designed to justify unnecessary industrial action to force higher wages.
Flights into and around Australia will be impacted, according to the United Firefighters Union which announced the results of a member ballot on Friday.
Some 93 per cent of members voted in favour of industrial action, including stoppages. Of the 574 voting members, 96 per cent voiced no confidence in the leadership of Airservices, a commonwealth corporate entity.
The union's aviation branch secretary Wes Garrett said shortages are undermining safety.
Major and regional airports across the country do not have enough firefighters to provide the protection required, he said.
"But despite our ongoing campaign and vocal calls for action on this issue, Airservices continues to deny that a problem exists, and refuses to take any meaningful action, putting the lives of air travellers at risk."
In a letter outlining its loss of confidence in leadership, the union said Airservices is "not performing its functions in a manner that is consistent with Australia's obligations".
A section of the Chicago Convention on International Civil Aviation, which Australia ratified in 1947, notes the principal objective is to save lives if an incident occurs.
The International Civil Aviation Organisation provides guidance on the required capability but does not mandate specifically how many personnel are required.
The union will meet next week to decide when, where and for how long they will take industrial action, and are likely to delay action until closer to the Christmas peak if it is taken this year.
Stoppages are expected to last between two and 12 hours, Mr Garrett said. The union will also have to give at least one week's notice of any stop-work action.
Claims of inadequate staff are not true, Airservices Australia said.
The corporation provides services at 27 Australian airports including Category 6 regional airports (such as Broome, Rockhampton and Port Hedland) up to Category 10 airports (Melbourne and Sydney).
The categories determine how much water, foam and personnel are required.
A standard shift at Melbourne or Sydney requires 14 personnel and three vehicles, as shown in figures approved by the Civil Aviation Safety Authority and presented to a Senate committee in 2019.
On the lower end, the regional airports require five staff and two vehicles.
The chief fire officer at the time for Airservices, Glenn Wood, told the committee the company had more firefighters on staff than the number approved by CASA at Sydney and Melbourne.
"We choose to provide three supplementary people to help us maintain categories ... we do need to still be able to respond to emergencies," Mr Wood said.
"The (union's) claims on staffing are not supported by the facts," an Airservices spokesperson said on Friday.
"Overall, the network requires 740 (firefighters) and there are more than 750 on staff at present and nearly 100 trainees entering the system over the next two years," the spokesperson said.
The dispute is really over wages, Airservices said, and it has offered a "generous" 11.5 per cent over three years, while the union seeks 15.5 per cent.
The federal government has announced an interim arrangement for a three per cent public servant wage rise over 12 months, less than the union wants or has been offered.
The Airservices board is required to satisfy itself employment conditions are consistent with commonwealth public sector requirements.
CASA has been contacted for comment.
