There were disruptions for travellers on Thursday morning, with hundreds of airport ground staff walking off the job over better pay and conditions.

Hundreds of Certis security workers and Qantas freight staff downed tools across the country at 7.30am and did not return to work until about 9.30am.

Workers on strike at Sydney Airport. Today

The staff walked off the job to call for better pay, more full-time work opportunities and a less fragmented workforce.

The industrial action took place at airports in Sydney, Brisbane, Perth and Adelaide.

Travellers faced longer lines at security and baggage drop-off while the strike took place.

There was also a planned two-hour stoppage from 6pm on Thursday and a three-hour strike on Monday at Sydney Airport.

Transport Workers Union national secretary Michael Kaine said people were concerned about “insecure work, highly casualised work, low guaranteed hours and poor”.

He said the workers were on the lowest pay in the industry.

“How does that make any sense when we’ve got qantas reaping in $2 billion worth of profit in this financial year,” Kaine said.

Sydney Airport has urged passengers to allow extra travel time and prepare for delays and disruptions.

“This is to send a message to Qantas and to Sydney Airport that all those millions that are getting in profit, they need a bit back here for fair pay, for secure jobs, so these workers can support themselves and their families,” Kaine said.

“It’s not a hard equation.”

Qantas said it did not anticipate the ground workers’ strike would interrupt services or cause delays for passengers.

Kaine said any disruption could be laid at the feet of Sydney Airport and Qantas.