SINGAPORE, July 17 — A contractor engaged by Singapore’s national water agency PUB for tank cleaning operations has been charged yesterday over alleged workplace safety lapses after two workers died following exposure to toxic gas at Choa Chu Kang Waterworks last year.

Channel NewsAsia reported that Stargroup was charged for failing to implement reasonably practicable measures to minimise workplace risks.

The company had been hired by PUB for routine tank cleaning operations at the waterworks.

On May 23, 2024, four workers from Stargroup and its subcontractor were cleaning a water treatment process tank when three workers later collapsed after entering an enclosed passage beneath the tank to close hand valves.

The three workers were taken to Ng Teng Fong General Hospital, where two died on May 24 and May 28, 2024. The third worker was discharged after receiving treatment.

According to the report, the Ministry of Manpower (MOM) said investigations found the workers had been exposed to hydrogen sulphide gas, a toxic gas that can be fatal even at low concentrations.

Sensors at the location had recorded hydrogen sulphide levels exceeding safe thresholds, and an alarm had been triggered at the time of the incident, MOM said.

The authorised manager for confined space entry permits at Stargroup, Lim Beng Hock, was also charged for allegedly failing to exercise due diligence in issuing the permits.

PUB said it took a serious view of Stargroup’s safety lapses and had blacklisted the company for 18 months from August 2024, preventing it from tendering for PUB projects during that period.

MOM also issued PUB the maximum composition fine of S$5,000 under the Workplace Safety and Health Act for allowing employees to enter confined spaces for short periods without adequate ventilation on previous occasions.

A PUB officer was also issued a stern warning for failing to cooperate with his employer to enable compliance with workplace safety laws.

MOM reminded employers conducting confined space work to carry out risk assessments, test atmospheric conditions, provide appropriate protective equipment and ensure trained standby personnel are stationed outside confined spaces at all times.