CHANDLER, Ariz. (AP) -- Investigators were trying to determine Saturday what caused the exhaust system of one of the high-tech tools inside Intel's manufacturing plant in Chandler to spring a leak and expose dozens of workers to nitrogen fumes.
The leak did not interrupt the making of any computer chip wafers or microprocessors, but it resulted in 12 contract workers being sent to the hospital. In all, the Chandler fire department treated 43 people after responding to the leak.
"What we saw was a lot of breathing issues, and we did see some skin irritation and eye irritation and a little bit of nausea from some of our patients," said Chandler Fire Battalion Chief Tom Dwiggins.
All of the patients were in stable condition, he said.
The leak was contained by 8:15 a.m., and Dwiggins said crews surveyed the area to ensure there were no more leaks before turning the area back over to Intel officials.
Company spokeswoman Rachel Sutherland said the leak originated with the exhaust system of one of the production tools in an area known as Fab 32, which is located at one of two campuses in Chandler.
Officials believe the leak may have been the result of a faulty O-ring, but the investigation was continuing, Sutherland said.
Two years ago, seven people were injured when a flash fire started inside a solvent-collection room at the plant. Later that year, eight people were treated for smoke inhalation after welders outside the plant caught nearby plastic on fire.
Intel has been operating in Arizona for more than 30 years and has about 11,000 employees between its campuses in Chandler.
The company has also invested more than $300 million to build a new research and development facility in Chandler. Billions more are being invested in the construction of a third semiconductor manufacturing plant, dubbed Fab 42, that will open later this year.