An office building in Metro Center was evacuated Thursday morning after several workers fell ill.
The five-story building is located at 2 Vantage Way off Great Circle Road and houses the offices of CGS Administrators, a health care company based in Nashville.
The location is a few blocks away from where a massive fire sparked underneath a propane tank earlier Thursday morning and the two events are unrelated, according to Nashville Fire officials.
The building was evacuated around 9:30 a.m. after workers complained of headaches, nausea and breathing difficulties.
Twenty-three people, primarily from the second floor, were taken to area hospitals with non-serious illnesses ranging from headaches to high blood pressure.
Some of the first people transported tested positive for elevated levels of carbon monoxide.
However, firefighters monitored the air when they arrived at the building and it was fine.
"We brought our HAZMAT crews in to actually monitor the air to determine if there was a chemical inside this building, specifically on the second floor. We could find nothing. We have not detected any type of chemical in this building," said Chief Dep. Kim Lawson.
It appears the situation was temporary. Officials are still looking for the source.
"This is the time of year anybody who burns any type of fuel should consider putting a carbon monoxide detector in their home," said Lawson.
In a statement, CGS Administrators spokesperson Adam Myrick said, "Based on the recommendation of emergency officials, we evacuated portions of our corporate headquarters in Metro Center after a number of employees reported various medical concerns. Air monitoring results do not indicate any threat to public health inside the building."
Employees have been allowed to reenter the building.
Myrick continued, "We'll continue to monitor the situation and work with first responders to ensure the health and safety of our valued employees."