A piece of faulty laboratory equipment caused an explosion at a Jurong industrial gas supply firm in October last year which killed a new mother and hurt seven others.
The blast was so powerful that it blew two workers off their chairs and caused part of the laboratory ceiling to collapse.
Calling 30-year-old Krysten Lim Siaw Chian's death a result of a "tragic industrial misadventure", State Coroner Marvin Bay yesterday urged companies involved in the storing and processing of volatile substances to comply strictly with safety precautions.
He said such firms must be "ever mindful of the catastrophic consequences that can ensue from any deviation from the stipulated specifications of component parts of equipment used in their industries".
Ms Lim, who had returned to work from maternity leave a month earlier, was a chemist at Leeden National Oxygen, which is involved in the storage, mixing and bottling of industrial gases such as hydrogen, helium, nitrogen and argon.
The 11.2m-by-6.6m laboratory she worked in had many gas cylinders filled with both inert and flammable gases, such as hydrogen, nitrogen and various hydrocarbons.
Ms Lim was analysing the components and concentration of gases from a cylinder containing methane, oxygen and nitrogen at about 9.30am on Oct 12 last year when a regulator valve suddenly leaked.
A joint in the valve had been welded together unevenly. But the joint was not supposed to have a welded component in it in the first place.
Heat was generated during the fracture of the metal valve and also when gas escaped through the failed weld joint, creating a spark.
The oxygen-rich environment allowed methane to be readily ignited. The fire then rapidly moved into the cylinder and the rapid overpressure resulted in the canister exploding.
The ensuing blaze engulfed the ground-floor laboratory in Tanjong Kling Road. All four of the laboratory's brick and concrete walls were dislodged. Ms Lim's charred remains were found on six occasions over a two-month period. They were identified using her infant daughter's DNA.
The wake for Ms Lim, who had received Singapore citizenship just a month before she died, was held in Skudai, Johor.
Outside the coroner's court yesterday, her husband, Mr Ooi Peng Fung, said: "It has been a painful year and it's challenging to raise my daughter as a single parent."
He said relatives are helping to look after his 11/2-year-old daughter, and added that he appreciated the effort put into investigating the cause of the accident but hopes that action will be taken to prevent such accidents from happening in the future. He declined to comment when asked if he was considering a civil suit against Leeden.