The death of a 42-year-old driver who was crushed by an oil tanker in January arose from an unfortunate confluence of events, a coroner said yesterday.

Mr Chun Kum Soon died after his truck rolled forward and pinned him against a concrete wall at the construction site of Sengkang executive condominium The Vales.

Among other things, the truck's brakes were faulty and it had been parked on a mildly declining slope, next to a 1.8m-high wall. And at the same time that Mr Chun left his truck to refuel an excavator, his vehicle rolled forward.

State Coroner Marvin Bay yesterday said Mr Chun's death was an unfortunate industrial misadventure.

"Mr Chun's sad demise underscores the importance of regular and scrupulous maintenance of all functional aspects of heavy industrial vehicles, as well as the need for operators of these vehicles to conscientiously observe basic safety precautions in the course of their work," said the coroner.

Mr Chun worked for Ming Hup Trading and had gone to the construction site at about 3.15pm on Jan 8. Closed-circuit television footage played in court showed him driving into the site and reversing into a narrow 3.8m-wide passage.

About two minutes later, after he turned off the ignition, Mr Chun left his truck to prepare the refuelling hose. He stood between his truck and a wall - a gap of 26cm.

But a minute later, the vehicle rolled forward by 3.62m. Mr Chun was pinned at chest level by the middle part of the 7m-long truck and began shouting for help.

Workers rushed to get help, but Mr Chun's cries grew softer and he became unresponsive two minutes after the accident. Emergency services took nearly half an hour to carefully extricate him, but he was pronounced dead on the spot.

Police and Ministry of Manpower investigators found the tanker's handbrake not fully pulled up. The court heard Mr Chun had told his wife the truck's brakes had issues, and had to be serviced occasionally.

After the accident, the truck's parking brake was found to be 6 per cent functional. The brake linings on the brake shoes were also worn and disintegrated.

Four timber bars and a timber block used as wedges for the truck's wheels were later found inside the truck. Mr Chun left behind a wife, in her 30s, and a four-year-old son.