The man was allegedly crushed after a crane lifting a large steel beam slipped and fell.

The 35-year-old man died on the scene, while another man was also injured during the accident.

Martin O'Malley, CFMEU C&G State Secretary, said the beam was being lifted with soft slings when the sling broke.

He said the workers had allegedly been instructed to use the slings instead of chains so the beams would not be scratched, avoiding the need for any rework.

Many companies use soft slings connected to cranes which wrap around steel beams, but they can easily break, putting workers at risk.

The family has requested not to speak to the media regarding this tragic incident and would like their privacy respected to allow them to mourn.

Police are preparing a report for the State Coroner and Safework SA is also investigating the incident.