Source: 23 May 2024, Channel News Asia
SINGAPORE: A PUB sub-contractor died on Thursday (May 23) after inhaling hydrogen sulphide gas while carrying out tank cleaning works at Choa Chu Kang Waterworks.
Two other workers who inhaled the gas are in intensive care. All three workers are foreigners.
The incident occurred at about 11.15am on Thursday.
“Three sub-contractor workers were carrying out routine tank cleaning works when they were found to have collapsed,” a PUB spokesperson said in a statement on Thursday afternoon.
“Preliminary investigations indicate that the workers had inhaled hydrogen sulphide, a gas produced from sludge which is a by-product of the water treatment process.”
All three workers were taken to Ng Teng Fong General Hospital in an unconscious state where one of them later died. Cardiopulmonary resuscitation was performed on one worker during the ambulance journey, said the Singapore Civil Defence Force (SCDF).
A spokesperson for the Ministry of Manpower (MOM) told CNA on Thursday night that the worker who died was a 40-year-old Indian national who was employed as a cleaning operations manager by Supersonic Maintenance Services.
The two injured workers are Malaysians.
One, aged 39, was also employed by Supersonic Maintenance Services while the other, aged 24, was employed by Stargroup Est. Both were employed as general workers.
TOXIC VAPOUR
In response to CNA’s queries, SCDF said it was alerted to a Hazardous Material (HazMat) incident at 11.25am.
Firefighters and HazMat specialists, wearing breathing gear, entered the area and identified the hydrogen sulphide.
Hydrogen sulphide is a colourless gas with a potent, unpleasant odour similar to that of rotten eggs or sewage. It is highly toxic and flammable.
Two water jets were used to disperse the vapour, said SCDF. This went on for an hour before HazMat specialists determined that there was no longer any hydrogen sulphide on the premises.
“PUB expresses our deepest condolences to the deceased’s family. We are in touch with our contractors and will render support to the workers’ family members,” the spokesperson said.
“Safety and health at all our workplaces are of utmost importance to PUB. We will cooperate fully with the investigation.”
As a precaution, the national water agency “has called a safety timeout for similar operations in confined spaces and is reviewing the associated safety measures”, the spokesperson added.
In response to CNA’s queries, PUB said that the safety timeout will apply to all its facilities and “will be lifted as and when we are satisfied that the necessary safety measures are in place”.
“The safety timeout will cover similar operations in confined tank spaces and PUB will ensure a thorough review of our safety procedures,” it said.
MOM said it is investigating the incident and has instructed PUB to stop all tank cleaning works.
The ministry added: “As a general safety measure, proper ventilation must be provided to prevent accumulation of toxic vapours. Workers must also be protected from excessive exposure to toxic vapours by equipping them with gas monitoring devices, and the appropriate personal protective equipment such as respirator mask and breathing apparatus.”
