All city schools will get carbon monoxide detectors by Dec. 1, CPS officials said Monday. View Full Caption DNAinfo/Heather Cherone

JEFFERSON PARK — All city schools will get carbon monoxide detectors after an investigation of an incident that sickened 89 people at a Jefferson Park school found "shocking things," Chicago Public Schools CEO Forrest Claypool said Monday.

When the boiler malfunctioned at Prussing Elementary School at 9:30 a.m. Oct. 30, the Jefferson Park school had no carbon monoxide detectors, which are not required by state law or city ordinance.

"Serious mistakes were made and problems revealed," Claypool said at a meeting Monday evening of the Prussing Local School Council.

More than 5,000 carbon monoxide detectors will be installed in public schools across Chicago by Dec. 1, Claypool said.

"We have learned a valuable lesson," Claypool said.

In addition, the Chicago Fire Department will change its protocol involving students evacuated from a school in a mass casualty event like the one at Prussing, Chicago Fire Department Commissioner Jose Santiago said.

Paramedics will be required to inform the city's Office of Emergency Management and Communications of each student's name and what hospital he or she is being taken to, Santiago said. That way, officials can give parents accurate information about their child's location, he said.

An effort is in the works to create a digital patient-tracking system with scannable bracelets to ensure that the location of all patients treated by paramedics is constantly available, Santiago said.

"That's the long-term solution," Santiago said.

Some parents of Prussing students said they waited to pick up their children for hours at Smyser Elementary School in Portage Park, where uninjured students were taken, only to find out they were still at Prussing Elementary School.

Other parents said they were sent to the wrong hospital to find their son or daughter, leaving them unattended for hours after being sickened by the poisonous gas.

"Far too much time elapsed between the incident and when parents were notified of where their children were,” Claypool said. “If I were a parent of a student here, I would have been enraged.”

In addition, principals will be retrained on the district's emergency protocols, Claypool said.

Several lawsuits have already been filed against the CPS in connection with the incident.

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