Following an incident at Choa Chu Kang Waterworks that took the lives of two workers and injured another, work has resumed for all PUB facilities, with the exception of Choa Chu Kang Waterworks.

Investigations ongoing

In a written reply to questions posed by Members of Parliament (MP) Poh Li San and Melvin Yong, the Minister for Sustainability and the Environment, Grace Fu, stated that as the Ministry of Manpower (MOM) is currently investigating the incident, she can only provide a limited amount of information.

The three contractor workers were performing a routine cleaning of a water treatment process tank at Choa Chu Kang Waterworks on May 23, 2024, when they were found to have collapsed, she explained.

Fu noted that initial investigations indicated they had inhaled hydrogen sulphide, a gas typically emitted when sludge is being drained from the tank.

Hydrogen sulphide sensors showed that levels of the gas were higher than normal at the time and location of the incident, she added.

Aftermath

As a precaution, PUB issued a board-wide safety time-out immediately after the incident, Fu said.

"During the time-out, PUB carried out comprehensive checks on its processes and safety procedures, both at Choa Chu Kang Waterworks and across PUB," she said.

Checks were specifically focused on managing work in confined spaces and locations where there are risks of exposure to toxic gases and chemicals.

Work resumed across PUB after confirming that safety procedures were adequate and in place, she added.

However, work at Choa Chu Kang Waterworks remains halted due to MOM’s Stop Work Order.

Fu expressed her condolences to the families and loved ones of the two workers who lost their lives.

She also wished the third worker a swift and full recovery following his discharge from the hospital on Jun. 22, 2024.

Non-constituency MP Hazel Poa also inquired whether the Ministry of Manpower could provide an update on the investigation into the incident and the safety measures being implemented to prevent a recurrence.

In a written reply, Minister for Manpower Tan See Leng stated that investigations are ongoing and they were unable to provide further details.

Regarding safety measures, Tan emphasised that workplaces must implement precautions to mitigate risks associated with working in confined spaces, as outlined in the Workplace Safety and Health (Confined Spaces) Regulations.

These measures include conducting gas tests by a competent assessor to ensure the atmosphere within the confined space is free from contaminants, ensuring effective ventilation, providing adequate worker training, using appropriate protective equipment, and having an emergency rescue plan in place.

Top photo from PUB/Facebook