It happened at 9:44 a.m. Wednesday at the DaVita Dialysis Center in the 300 block of Callowhill Street.
Initial reports indicated some kind of chemical may have been poured into a drain at the facility, producing strong fumes.
First responders evacuated the facility as they investigated the source.
The incident was under control by 10:30 a.m., officials said.
One person was taken to the hospital for observation.
Officials said the cause of the fumes was work being done by a Verizon cable crew.