IRVINE – Two UCI science students were performing standard late-night research Tuesday when they became ill after inhaling toxic fumes coming from another experiment, which ultimately prompted the building to be evacuated and three campus custodians to be briefly hospitalized, officials said.

Orange County Fire Authority officials responded to reports of a possible chemical spill around midnight at the UCI campus after a custodian crew responded to the classroom and became ill, OCFA Capt. Steve Concialdi said.

Twenty-five firefighters, 10 of whom are hazardous material specialists, arrived at the biochemistry building, at 517 Biological Court, and the hazmat team geared up in full-body gray suits.

With tape around their ankles and wrists and breathing apparatuses to provide them with clean air, they pulled the fire alarm to make sure everyone was out of the building before canvassing it.

Around 1:45 a.m., officials determined a containment box found in the classroom where the two research students were working is where the fumes originated. It’s suspected that the box leaked a noxious gas while in a self-cleaning mode, Concialdi said.

(A containment box is a sealed container, clear and usually the size of a large fish tank, that is designed to allow scientists to manipulate hazardous substances by using attached gloves.)

Fire authorities did not know what the gas was, only that it caused the researchers, as well as the five-person custodial crew to become dizzy, nauseous and experience shortness of breath.

Three of the custodians, a 36 and 34 year old man and 32-year-old woman, were taken to Hoag Hospital in Irvine with minor injuries and all were released before dawn, Concialdi said.

UCI police deemed the campus building safe around 2:30 a.m.

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