A man killed in a workplace accident which has left a second employee fighting for life has been remembered as a “beautiful soul”.

Paulo Mau’u, 40, and colleague Aymen Alahmad, 30, suffered critical injuries at a Meriton construction site on Pennant Hills Rd, near Shirley St, in Carlingford, in Sydney’s northwest, about 9am on Tuesday.

Mau’u was taken to Westmead Hospital while Alahmad was taken to Royal North Shore Hospital.

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Mau’u later died in hospital while Alahmad remains in a critical condition fighting for life.

It’s believed the men were injured by concrete pumping equipment.

Tributes have begun pouring in for Mau’u, with devastated loved ones urging others to “never take life for granted”.

“We never really know when the last time you see someone is the ‘last time’,” one friend said.

“RIP ma uso (Samoan for “my brother”). Couldn’t believe the news, will forever miss your good vibes and energy.

“Love ya ma uso. You truly will be missed.”

“Rest in peace brother,” another friend wrote. “I’m really hurt. Never forget you.”

According to his social media profiles, Mau’u was a “proud Samoan” who migrated to Australia from New Zealand.

Meriton on Tuesday said the company was “devastated” by what had happened.

“Our hearts go out to their families, friends, and colleagues during this incredibly difficult time,” it said.

“We extend our deepest condolences and stand with them in their grief and pain.”

Meriton said safety at its construction sites was its highest priority and it was “co-operating fully” with SafeWork NSW.

Police are investigating and the incident has been referred to SafeWork NSW.

There was another incident at the same worksite in June when roads were closed due to an unstable crane.

One or two of the crane’s two anchor pins had failed, causing it to tilt at the base.

At least 350 workers and nearby residents were evacuated as a precaution.

No one was injured.