Dust build-up could have led to Jiangsu factory disaster, says expert
The deadly explosion at a car parts factory in Jiangsu could have been caused by the ignition of accumulated dust although the mainland had safety standards aimed at preventing such accidents, a work safety expert said.
Metallic dust would have been a "major" risk at the factory, which polished car wheels, Zhang Xiaoliang, an associate professor of work safety engineering at the Shanghai Institute of Technology, said in an interview on Sina.com.cn.
"The explosion occurred in the polishing workshop. Polishing generates metallic dust, which is extremely fine, sometimes smaller than one micrometre," he said.
Besides iron, other metals such as aluminium and magnesium could have been present. If mixed together at a high enough concentration, a spark could trigger an explosion.
"The heat can reach 2,000-3,000 degrees Celsius, which is much hotter than ordinary fire," Zhang said. That could blow a building apart, collapse walls and seriously burn victims, he said.
Zhang said metallic dust may have fallen on the floor, which is why factories used air ventilation or dust removal systems to avoid an accumulation.
While workers were probably aware of the danger the dust posed to bodily health, they might not know it was also highly flammable, he said. The powder can be so fine that workers would not see it, he added.
Zhang said the trigger for the explosion could have come from many sources, such as welding, electronic devices or even a hammer dropping on the floor.
In May 2011, three people were killed in a dust-related blast at a Foxconn factory in Chengdu, Sichuan province.
Zhang said the government had launched an effort to address dust explosion risk in 2012 but accidents continued to happen.