Even when he knew he was risking his life, Mr Zhai Hailei jumped in to save his friend.
Sadly, Mr Zhai, 25, and Mr Yang Zhonghua, 37, died days after being found by other colleagues in a waste-water pit.
Both Chinese nationals were employees of Nam Heng Leather Dyeing at Tai Seng Industrial Estate, near Upper Paya Lebar Road, where the accident happened on Dec 26 last year.
At work, Mr Zhai and Mr Yang would often spend time chatting during their breaks.
On their days off, the two were just as inseparable.
After the accident, the good friends died within hours of each other on Jan 4 - Mr Yang at 10.55am and Mr Zhai at 8.30pm.
In his findings yesterday, State Coroner Marvin Bay said the deaths were "misadventures of an industrial nature".
He said Mr Yang most likely fell into the water, which was 2.5m deep, as he was disorientated by the harmful hydrogen sulphide fumes in the vicinity while "perched precariously" above the water pit (also called a sump).
Mr Bay said: "(Mr Zhai) perished as a result of his valiant, but ultimately futile, attempt to save his co-worker and friend."
On Dec 26, Mr Yang had reported for work as usual at 8.30am and company foreman Chew Hock Seng, 61, told him to collect two plastic sieves that were hooked onto a metal beam directly above the sump.
A closed-circuit camera captured Mr Yang entering the sump area at 8.48am and he disappeared soon after.
Suspecting that he could have fallen in, Mr Chew asked Mr Zhai to search the area.
The camera captured Mr Zhai near the sump and he, too, disappeared moments later.
After five minutes, a panic-stricken Mr Chew alerted all the other workers to search for the two men.
He told his manager, Mr Ang Keat Hong, 39, about the situation and the younger man went to the sump to look for the workers.
As Mr Ang was removing a makeshift platform made of wooden planks there, he caught sight of an unconscious Mr Yang in the water.
The Chinese national was pulled out and his friend, who was also unconscious, was spotted minutes later.
Both men, who were wearing slippers instead of anti-slip safety boots, were rushed to Changi General Hospital but died eight days later.
They died due to a deprivation of oxygen to the brain with blood poisoning, following a near-drowning.
Mr Bay said yesterday that a person attempting to retrieve the sieves on that day would have to be perched in a very precarious position - a squat.
The person would also have to crane his head forward to properly locate and get hold of the sieves.
He said: "The unsteady weight distribution would predispose a person to fall over if he slipped or was temporarily disorientated by a moderately high concentration of hydrogen sulphide gas, as I believe would have been the case here.
"The disorientation by the gas would have further compromised his ability to call for help or struggle once he was in the water."
The coroner said that the level of hydrogen sulphide near the sump was found to be 9.2 parts per million (ppm) at 5pm that day.
Because the incident took place about eight hours before this reading was taken, he said that the level of the gas there was most likely significantly higher earlier in the day.
At 9.2ppm, the gas can cause eye irritation.
"The gas, which attacks the central nervous system, can in progressively higher concentrations cause… dizziness, fatigue and weakness," he said.
He said Mr Zhai, who was known to have an impulsive streak, most likely mounted a single-handed attempt to rescue his friend.
Mr Ang, who was present when the coroner delivered his findings, told reporters outside the courtroom that his company had stepped up their safety measures following this tragedy.
He said that the sump is now covered by grating and two ladders have been installed in it so that workers who fall inside can easily climb out.
Besides ensuring that its employees don safety boots, he said that the company had also installed more lights near the sump and improved ventilation.
Mr Ang said that the company had already given monetary compensation to the dead men's families. But he declined to reveal the amount.
He said: "The coroner's findings are fair. It was an unfortunate incident. The accident shouldn't have happened."
This article was first published on Oct 22, 2014.
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