CHICAGO (WLS) -- Almost 40 U.S. Postal Office employees at a River North facility were treated Saturday morning for heat-related illnesses, including dizziness and nausea, after temperatures inside the building reached nearly 100 degrees, a Chicago fire official said.
Thirteen employees were hospitalized and another 23 workers were treated at the scene of the facility at West Ohio and North Dearborn streets.
"It's hot in this building. Extremely hot. No air conditioning," said postal worker Kenneth Norman early Saturday.
An air conditioner had malfunctioned, a USPS spokesman said. Employees said temperatures were nearly 100 degrees since mid-week.
On Saturday, employees were working at the facility since 5 a.m. A supervisor who was throwing up was among those who were treated. A CTA cooling bus was also sent to the scene.
"You go through the door...you could feel like an oven on and you can't open windows up there so everybody just started getting dizzy and throwing up, getting sick," said postal worker Aileen Harris.
The facility was evacuated and closed on Saturday, and will remain closed on Sunday. The closure impacted three zip codes - 60610, 60611 and 60654 - where residents did not receive mail on Saturday.
The facility will resume normal service on Monday.
"We're not going to have the rest of our employees work in there, it's clearly unsafe," said USPS Chicago District spokesperson Mark Reynolds. "We value the safety of our employees."