The incident occurred in August 2012 when workers from Sing Wah Enterprise were called to electronics company Toshiba Tec Singapore to remove a hydrocarbon refrigerant from an air conditioning at its factory.
The call was in response to a Singapore Civil Defence Force (SCDF) circular announcing its intention to ban the use of hydrocarbons in existing air cooling units. Hydrocarbon refrigerant and technology suppliers in Singapore were first informed of the ban in 2010 when the SCDF said it had “decided not to continue to allow the use of HC as refrigerant in air conditioning systems owing to the hazards it imposes on the safety of occupants in buildings.
At the inquest in 2013, it was revealed that the workers carried out chemical flushing of the air conditioning coil and released the hydrocarbon refrigerant gas by using a hose connected to the compressor. One of the workers was tasked to remove waste water on the floor, but as soon as he switched on the vacuum cleaner, there was an explosion which caused a flash fire.
The coroner said that the refrigerant conversion process had caused the accumulation of hydrocarbon gas in the room and that a spark from the vacuum cleaner ignited the gas and this caused the explosion and fire.
All three workers were taken to hospital with burns. Bangladeshi worker Abadul Jaynal Sikder died in hospital four days later.
The coroner concluded that the workers probably didn’t understand the dangers posed by the gas in the air conditioner they were working on. Because of that, a spark from a vacuum cleaner turned what seemed like a straightforward task into a deadly one.
According to a report on the website of the Singapore newspaper Today, a district court has ordered Sing Wah Enterprise to pay a fine of SGD150,000 (€100,000) for failing to ensure the safety of the three workers.
Investigations were said to have shown that Sing Wah had not provided a risk assessment or safe work procedures for the gas conversion works assigned to the workers.
The workers also did not have a copy of the safety data sheet on the gas. Also the equipment used, such as the vacuum cleaner, was not explosion proof.
The court was urged to impose a lenient fine, as Sing Wah had not shied away from its responsibility, and had compensated the workers SGD350,000 (€230,000) in medical bills and repatriation fees.
Hydrocarbon refrigerants are being phased out in building air conditioning systems in Singapore by the end of 2016. They are also being banned in mobile air conditioning and commercial refrigeration systems such as coldrooms in supermarkets, food storage factories and industrial process refrigeration systems. Strict controls and safety measures have also been placed on their use in domestic refrigeration and small residential air conditioners.