Chemical Industries (Far East) Limited was fined $200,000 for a chlorine leak from a 1-ton container at its Jalan Samulun storage facility, which occurred on 4 September 2016.
In a press release on Monday (24 September), the Ministry of Manpower (MOM) shared that two emergency responders and five members of the public outside the workplace were exposed to the escaping chlorine gas in this accident.
The authority stated that chemical Industries (Far East) Limited had pleaded guilty to a charge under section 12(2) of the Workplace Safety and Health Act for failing to take reasonably practicable measures necessary to ensure the safety and health of persons who may be affected by its undertaking.
On 4 September 2016, liquid chlorine leaked from a 1-ton cylinder (“ton container”) stored in a chlorine storage facility occupied by Chemical Industries (Far East) Limited. The leak triggered an alarm from one of the chlorine detectors installed, and a worker activated the chlorine gas emergency scrubber and exhaust system.
Two workers then donned personal protective equipment and attempted to stop the leak, but were unsuccessful. Chemical Industries (Far East) Limited then called in the SCDF, and the leak was mitigated shortly after.
Two SCDF responders and five members of the public outside the workplace were momentarily exposed to the leaked chlorine gas. They were admitted to Ng Teng Fong hospital for treatment, ranging from eye irritation to difficulties in breathing, and were discharged on the same day.
According to the ministry, investigations revealed that the company had failed to maintain the integrity of the fusible plug of the chlorine ton container, which was found to be severely corroded and resulted in the leak.
A fusible plug is a fitting fastened onto the ton container to relieve the internal pressure inside the container in the event of an external fire. The company did not conduct any inspection of the fusible plugs during the external inspection of the ton containers prior to each filling, which would have revealed pre-existing corrosion damage of the fusible plug.
It then said that the company also failed to establish and implement a detailed and effective emergency response plan (“ERP”). The company’s ERP covered the scenario of a chlorine leak and assumed that the chlorine would leak slowly as a gas instead of liquid under pressure. The emergency response for liquid chlorine leak scenario was not documented under the ERP.
The ministry stated that on the day of the leak, the ton container had to be rolled over to position the leaking fusible plug to its topmost position which would convert the liquid leak to a gas leak. Converting to a gas leak would reduce the rate of chlorine mass leaking out of the corroded connection significantly, allowing emergency responders to approach the ton container and seal the corroded connection preventing further leaks.
However, when the incident occurred, the worker was unable to do so as the leaking container was stored between many other ton containers with no gaps. The company’s ERP for a liquid chlorine leak was thus ineffective.
Investigations by MOM also revealed that the company failed to install its emergency scrubber and exhaust system according to design and maintain a safe air change rate in the workplace. There were 12 suction pipes located inside the perimeter of the building to extract air from the warehouse.
Some of the suction pipes within the warehouse were found to be covered with mesh filters, and no calculations were conducted to verify that these filters would not reduce the flowrate of air into the emergency scrubber and exhaust system.
Air flowrate measurements from the suction was not conducted to verify the efficiency of the exhaust system, and investigations revealed that the rate at which the contaminated air was extracted did not meet general ventilation standards.
Er. Go Heng Huat, MOM’s Director of the Major Hazards Department, said, “The company had failed to properly maintain and store the ton containers, establish a proper emergency response plan to address chlorine leaks and implement an effective exhaust system for extracting and channelling contaminated air to the scrubber."
"The multiple safety breaches showed a clear disregard of the hazards at the workplace and had posed a safety risk to the public. The MOM will not hesitate to prosecute companies that flout safety regulations," he added.