National Jewish Health spokesman William Allstetter says most of those evacuated Monday were staff members. About 35 people were taken to other hospitals for treatment, mostly for nausea and respiratory irritation.
The evacuations included about 90 children who were at the hospital.
Allstetter says chlorine and hydrochloric acid were spilled or inadvertently mixed during maintenance work at a swimming pool on the hospital campus.
Allstetter says three buildings were evacuated, but the main hospital wasn't affected and doctors are still seeing patients.
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