Hazardous materials crews from Scottsdale and Phoenix cleared a Scottsdale meat storage plant of carbon monoxide after several workers complained of headaches Friday morning.
One worker drove himself to a hospital while three others were taken to hospitals as a precautionary measure, said Jay Ducote of the Scottsdale Fire Department.
In all, nine workers complained of headaches about 7 a.m. when the call was received and nearby businesses were evacuated, Ducote said.
Hazmat crews found high readings of carbon monoxide in the plant warehouse at 7862 E. Gray Rd., in the area of Hayden and Thunderbird roads.
Crews ventilated the area until the CO level returned to normal, Ducote said.
The problem was caused by a propane-powered forklift that was taken out for inspection, Ducote said.
Owners were eventually allowed back into their businesses, he said.
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