The Subsea 7 site is a major load-out facility for the Chevron-operated Gorgon LNG project.

The shutdown ended on May 31.

Maritime Union of Australia WA assistant state secretary Will Tracey said the closing of the Subsea 7 site for 10 days due to a series of safety incidents was "just the latest in a long line of management stuff-ups, which are damaging this project [Gorgon]".

On May 13 a 250-tonne crane rolled over onsite during a slewing manoeuvre.

It was followed two days later by a Tutt Bryant 25t Franna crane also tipping over while moving 10t counterweights.

On May 18 there was almost a third crane toppling incident. A Sarens 350t was lifting mooring equipment in and around a barge with its boom extended when it bounced on its outriggers.

According to a witness that incident could have led to the third crane collapse on the site in that week.

Then on May 21 a BAE contractor fell into the water between a barge and the wharf at about 8.50pm.

It appears the worker was not "buddied up" and nobody actually saw him go into the water.

Fortunately it seems two workmates heard the splash and went to investigate and they were able to get him out of the water.

Tracey said the site shutdown had been sparked by Chevron.

A Chevron spokeswoman said the company worked closely with all of its contractors to promote a safe workplace.

"Operations at AMC were temporarily ceased by Subsea 7 at the time of the incident in order to conduct detailed reviews of existing safety procedures and practices and to remind all workers to follow the safety procedures.

"Operations have now resumed.

"Gorgon remains on schedule for first gas in mid-2015."