A small explosion injured seven people yesterday afternoon at Intel's wafer-baking factory in Chandler, Arizona.

According to various reports, the explosion took place in a part of the Chandler facility that is being upgraded to support 22 nanometer chip fabrication, which Intel will ramp up later this year using its Tri-Gate 3D transistors.

Brad Miller, battalion chief at the Chandler Fire Department, told Reuters that the explosion, which he characterized as a "small blast", took place at around 2pm local time and that fire-suppression systems using water and foam quickly smothered the resulting blaze. The explosion was initially reported by Miller as taking place inside the chip plant, but it actually occurred in a support facility for storing chemicals.

An Intel spokesman told Reuters late last night that it was not an explosion at Fab 32, as the facility is called by Intel, but rather a brief fire. This would be inconsistent with battalion chief Miller's report that one of the seven people wounded at the Chandler facility suffered from shrapnel wounds; six others had less serious injuries, but a total of four were hospitalized last night.

The Chandler plant, like other Intel facilities, is heavily automated, and the explosion in the new 22 nanometer facility at Fab 32 had no effect on chip production in other parts of the fab, even as the running factory was evacuated as a safety precaution.

Fab 32 was opened in October 2007 and was Intel's first 45 nanometer fab and was upgraded to 32 nanometer processes in 2009. The factory employs over 1,000 people and makes tens of millions of chips per year.

The Chandler factory is one of three different chip plants that Intel operates in Arizona. The Fab 12 and Fab 32 facilities in Arizona are expected to account for the bulk of Intel's 22 nanometer production later this year. It is unclear at this point what effect the explosion/fire will have on the 22 nanometer ramp, if any. ®