Intel officials say they have pinpointed the source of a gas leak at the company's plant in Chandler, but they have yet to determine what caused it.
Dozens of employees were evacuated from the plant Saturday morning when the leak was detected.
Intel spokesman Jason Bagley said Monday the leak was traced to a fitting on the exhaust system of one of the plant's high-tech tools.
The leak didn't 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. They had complained of breathing difficulties, skin and eye irritation and nausea.
Authorities initially believed the leak involved some type of nitrogen fumes, but Bagley says there was likely a mixture of gases in the line at the time.