At least 35 people were treated after a maintenance worker accidentally created a gas that caused peoples lungs to fill with fluid at the Shadow Brook Elementary Swim Club in San Jose Thursday.
Emergency crews arrived at the scene at 1079 Shadow Brook Drive and began decontaminating multiple people, mostly children ages 10 to late teens, who were then transferred to the hospital as a precaution, officials confirmed.
"Very scary," said parent Sayed Haq. "I didn’t know it was going to be a big deal until I got here. Apparently it was pretty serious."
Witnesses say swimmers began saying they were feeling nauseated and some were coughing just before noon.
The maintenance worker reportedly mixed chlorine and muriadic acid by mistake, creating the gas.
"Chlorine gas can produce some serious symptoms if you inhale it," said Captain of the Santa Clara County Fire Department, Bill Murphy.
Patients were transferred to Valley Medical Center, Kaiser Medical Center and Stanford Medical Center.
"Its pretty scary," said Sayed. "Especially when kids are involved. All parents would be concerned."
No additional information was immediately released.