CFMEU assistant secretary Joe McDonald.

The building industry watchdog has launched Federal Court action against WA's construction union and its assistant secretary Joe McDonald for the second time in 20 days over worksite conduct at Perth's new children's hospital.

Among the respondents listed for the latest action are Construction, Forestry, Mining and Energy Union national secretary David Noonan, WA secretary Mick Buchan and Mr McDonald.

Fair Work Building and Construction last night issued a statement alleging the CFMEU organised and controlled a blockade, involving up to 600 people, at the $1.2 billion hospital project site on July 18 last year.

The action prevented a "critical" concrete pour, which the FWBC says the union had prior knowledge of, in an alleged bid to coerce head contractor John Holland to agree to enterprise agreement demands.

"FWBC is alleging the unions and Noonan, McDonald, Buchan and (organiser Tawa) Harris knew . . . any disruptions to the concrete pour would affect project completion and contractual milestones, and that this would expose John Holland to significant financial detriment," a FWBC statement said.

"By 8.30am on July 18, about 600 people were gathered at the main site entrance. Access to the site was blocked and the concrete pour subsequently did not happen."

The crowd then moved to a nearby park where Mr Buchan allegedly stood on the back of a utility with a microphone and allegedly said: "We can pull the numbers when- ever we need them and we'll do whatever we need to do." Mr McDonald allegedly said: "We are the union and we called the shots today."

Earlier this month, FWBC began legal proceedings against the CFMEU, Mr McDonald and Mr Buchan over moves to block non-union "scabs" from entering the hospital site on May 3 last year, including allegedly gluing the locks on a shut gate.

A spokeswoman for John Holland said the company would not comment. The CFMEU was contacted for comment.

The West Australian

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