SINGAPORE, Dec 6— A supervisor at an oil refinery on Jurong Island failed to ensure that hazardous gas and liquid pipelines were safely isolated before issuing a permit for workers to carry out maintenance works.

As a result, the sudden release of hydrogen sulphide and other hazardous material killed one worker, who suffered extensive chemical burns, and injured two others.

Ng Teck Chuan, 51, was sentenced to five months’ jail today after he pleaded guilty to committing a negligent act under the Workplace Safety and Health Act by approving works to be carried out without ensuring this could be done safely.


The incident happened at the plant, operated by Singapore Refining Company (SRC), on September 17, 2020.

Ministry of Manpower prosecuting officer Melvyn Low told the court that at the time of the accident, Ng was SRC’s senior process (day) supervisor and permit issuing authority. He had worked for SRC for 26 years.

Ng was trained in maintenance processes known as system blinding and de-blinding, steam-out, and repair work follow-up during maintenance or major work preparation.


He was also trained to issue permits related to this work.

System blinding refers to the inserting of objects known as spectacle blinds into the pipelines at a defined boundary between two processing units to stop any process flow and isolate one processing unit from the others.

The accident

On September 17, 2020, the gas desulphurisation (GD) unit and the amine treating (AT) unit had been shut down in preparation for maintenance which takes place every 4.5 years.

The GD unit’s function is to remove impurities such as sulphur from distillate fuels while the AT unit removes hydrogen sulphide from sour off gas — a by-product of a chemical process in petrochemical refining and waste-water treatment.

The deceased Palanivel Pandidurai and his colleague were tasked to carry out system blinding works of the GD unit while a foreman, who was in charge of both of these workers, supervised other system blinding works on another platform.

At around 5.55pm, after inserting the spectacle blind into one of the pipelines, there was a sudden release of low pressurised hydrogen sulphide gas and hazardous liquid material when Palanivel and his colleague re-tightened the bolts.

Both of them were overcome by the gas and collapsed.

The foreman was alerted to the incident and attempted to rescue the two workers but was also overcome by the gas and collapsed.

The three were eventually rescued and taken to Ng Teng Fong General Hospital.

Palanivel sustained partial chemical burns on 40 per cent of his total body surface area and had extensive blistering and peeling of the skin over his upper abdomen and back.

The court heard that he also suffered from breathing injuries due to the hydrogen sulphide exposure and later developed multiple organ failures during his stay in the intensive care unit. He succumbed to his injuries a few days later.

His colleague sustained superficial burns to his upper back, hip area and legs while the foreman suffered chemical injury to both eyes as well as abrasions to his mid-back region.

The negligent act

Investigations revealed that on the morning of September 17, the SRC operations morning shift team took over the duties from the midnight shift team, and were informed that the GD and AT units were not yet ready for system blinding works.

Ng then tasked his senior operations technician to prepare the pipelines for system blinding works, which included ensuring that sections had been made safe through proper isolation, and to update him on the status.

Even though Ng did not know the exact number of pipelines that were ready or whether exact precautions had in fact been taken to isolate the pipelines, Ng still issued a permit for system blinding works to commence.

This went against SRC’s internal safety regulations which required the job sites and all necessary isolations to be checked and considered safe before work could commence.

Low told the court that Ng, as the permit issuing authority, was responsible for ensuring that the relevant GD unit sections were safe.

This was critical to addressing the foreseeable risk of release of remnant pressurised hazardous gas and liquid left in the unit, he added.

‘Importance of workplace safety’

In seeking a jail term of between five and six months, Low said that Ng was the type of offender that the Workplace Safety and Health Act aims to deter.

He added that Ng was in a supervisory role to ensure that the maintenance works could commence safely before issuing the permit, and had been trained for this role.

“The court ought to impose a sufficiently deterrent sentence to not only highlight the importance of workplace safety but also to deter like-minded individuals in similar positions from committing similar offences,” said Low.

For committing a negligent act which endangered the safety or health of others, Ng could have been jailed for up to two years or fined up to S$30,000 (RM104,464), or both. — TODAY