Irish national Barry Breslin has been identified as the worker killed in a workplace incident on a Perth highway

A 35-year-old man killed at a construction site next to a busy Perth highway has been identified as a “beloved” father and fiancé from Ireland.

Barry Breslin, from Straleel, Kilcar, received an outpouring of honors after he was critically injured in an incident involving an excavator just before 12pm on Thursday.

It happened on the southern exit of the Mitchell Fwy to Warwick Rd in Greenwood, in the city's northern suburbs.

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The worker suffered serious head injuries and was taken to Royal Perth Hospital, where he died a short time later.

“The tragic death of Barry Breslin occurred following an accident in Perth, Australia,” an obituary reads.

“Beloved father of his son Tommy. He is sadly missed by his loving fiancée Melissa, his parents Mary and Seamus, his brothers Owen (Beth and Hazel) and Shane (Gerard).”

Funeral arrangements have not been announced.

Breslin's former Gaelic club CLG Cill Chartha said he was “shocked” by his death.

“Barry played for the club at an underage level for many years and is fondly remembered by the players and everyone involved at the time,” the club said in a post on social media.

“To his mother Mary, a tireless volunteer and supporter of our club over the years, our thoughts are with you and your family and we extend our prayers to you all at this sad time.”

In another tribute, Breslin was described as a “good young man.”

“Sincere condolences to the Breslin and Byrne families on the loss of Barry,” the post reads.

“A good young man whose life was taken too soon. May Barry rest in peace forever.”

The WA branch of the CFMEU said Breslin was working on the Smart Freeway project when he died.

“Our investigation has only just begun,” the union said.

“We know the incident involved an excavator and lifting equipment (but) we will not speculate on the tragic circumstances until we have the facts.

“All we know is that tragically one worker did not return home today.”

WorkSafe investigators are now investigating how the fatal incident occurred “to ensure compliance and prevent future incidents of a similar nature.”

“The man was reportedly struck by a piece of falling equipment,” WorkSafe said.

Commissioner Sally North said work-related deaths were a tragedy and expressed her condolences to the man's family.

According to the CFMEU, Breslin's death is the 10th construction fatality in Washington this year.

A report will be prepared for the coroner.