CHENGDU, CHINA -- A build up of combustible dust, a safety scourge in the woodworking industry, was implicated in the fiery blast that killed three workers and injured 15 others last week at the FoxConn Technology factory where the iPad2 and other Apple products are manufactured.

The blast is believed to have occurred in the facility's polishing shop, according to multiple news reports. Foxconn said in a statement that it has closed down that plant, and all others carrying on similar work, so that it can conduct a complete safety inspection and determine what caused the explosion.

"The cause of this tragic accident is still being investigated by a joint investigation task force led by government officials and law enforcement authorities, but that task force has communicated initial findings that the accident was caused by an explosion of combustible dust in a duct," the company said in a statement. "Foxconn is cooperating fully with all relevant government bodies to carry out a full investigation into the specific root cause of the accident and the company is taking all necessary actions to ensure the safety of employees at this and all other production facilities."

A representative of the Hong Kong-based Students & Scholars Against Corporate Misbehavior, said workers at the plant told them that the polishing department windows were shut and there aluminum dust was visible floating in the air.

The company said it had a one week of inventory of the iPad2. The plant also manufactures Apple's iPhone 4.

Chinese officials have asked Foxconn Technology Group and other Taiwanese companies to take greater efforts to ensure the safety of workers in their mainland China factories.Foxconn's treatment of Chinese workers came under scrutiny last year following multiple reports of Foxconn workers who committed suicide after allegedly being pushed too hard to meet the world demand for Apple products.

Foxconn is a division of Hon Hai Precision Industry Co., which manufactures mobile phones, computers and other products under contract for Apple Inc., plus Hewlett Packard Inc. and other companies.The company employs more than 1 million people in China at numerous huge factory operations.

The Occupational Safety and Health Administration is in the process of gathering information that could be used to create a mandatory combustible dust standard, including for wood dust.

Posted by Rich Christianson

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