Orange County Fire Authority firefighters responded to the hazardous materials situation just before 9:15 a.m. Friday in the 6500 block of Caballero Boulevard, according to the agency.
OCFA officials initially said 12 employees at the business were decontaminated, and 11 were taken to hospitals. By the end of the day, a total of 14 people had been treated, and 13 were taken to hospitals, all of them described as being stable.
Late Friday night, OCFA officials said the leaking material was determined to be ammonia, and the leak had been capped. It was unclear what caused the leak.
On Saturday, fire officials said cause of the release was determined to be accidental due to equipment striking an ammonia distribution line.
City News Service contributed to this report.