Two workers have been injured on Curtis Island, with one airlifted to hospital, prompting the CFMEU to question the safety measures being implemented on the Bechtel site.
Bechtel is investigating the cause of the accident, which occurred on a compressor deck at the QCLNG site while employees were moving a crane rail along a structural steel beam.
"During the process, a section of the crane rail slipped from the beam and dropped onto a team member's foot. A second team member was also grazed by the rail," Bechtel Gladstone general manager Kevin Berg said.
An emergency response team was called to treat both men, with a rescue helicopter called to take one of the workers to Rockhampton Hospital, The Observer reported.
"As a precaution, the employee with the foot injury was evacuated by helicopter to Rockhampton Hospital where it was determined he received fractures to bones in his foot," Berg said.
Workplace Health and Safety were notified of the incident, as were employees.
CFMEU representative Ben Loakes said he was concerned accidents would continue on the site.
"I think there is the potential to lead into something more serious than what we have today," he said.
"(Bechtel has) a lot of their American safety officers that wouldn't know their Australian legislation."
Berg called the claim "ridiculous" and said safety was taken seriously on the island.
"Safety assurance is proactively managed by supervisors, superintendents, area superintendents - who are predominantly Australians," he said.