UPDATE: 12:30 PM TUESDAY: TVA is continuing to look into what caused a pipe to burst Monday morning in a fire suppression system, leading to the release of a fire suppressant within the utility giant's data center downtown.
Spokesman Jim Hopson told 10News on Tuesday that the suppressant was in fact what's known as Ecaro and not halon gas as first thought.
Ecaro is an agent that's stored in sealed cylinders and then released through nozzles that operate within a piping system, according to the maker. Ecaro acts similarly to halon, Hopson said, but doesn't cause ozone depletion as the older and since discontinued halon system does.
A pressurized pipe within the suppression system burst, according to Hopson. The Ecaro agent then got into the data center and surrounding areas, he said.
Ecaro is used specifically because it won't damage sensitive equipment such as computers. The data center was not affected by the release, although there was minor damage around the piping where the actual burst occurred, according to Hopson.
"There were no interruptions to TVA's information technology systems, which are designed with multiple backups in various locations that provide a robust level of redundant capabilities," Hopson said in a statement to 10News.
The East and West Towers were evacuated as a precaution. Employees went back in about 12:30 p.m. Monday.
PREVIOUS STORY: A rupture in a Halon fire suppression pipe caused employees to evacuate the TVA data center in the east tower in Downtown Knoxville Monday morning.
Initially, there were reports of an explosion by people in the area. However, the Tennessee Valley Authority said there was no fire and no explosion.
Knoxville Fire Department Captain DJ Corcoran said the fire alarm call came in at 10:45 a.m. He said the TVA employees self-evacuated.
The data center is the the basement. According to authorities on scene, three people were in the room at the time.
In a tweet, the TVA also said there were no injuries and all employees were accounted for.
While the incident happened in the east tower, as a precaution, both towers were evacuated involving roughly 1,000 people, investigators said.
The burst released halon gas, according to authorities on scene.
Halon is a liquefied, compressed gas that stops the spread of fire by chemically disrupting combustion. It is used as suppressant in place of traditional suppresants, such as water, because it won't hurt valuable equipment like computers.
The Knoxville Fire Department was still on scene at 11:30 a.m. Monday and said it's unclear what caused the burst. At this point, it's being called a maintenance issue.
Crews plan to flush out all the halon gas that escaped before allowing employees back into the building. Authorities on scene said it's unclear how long that process will take.
No fire or explosion at TVA towers in downtown Knoxville. Rupture in Halon fire suppression pipe caused employees to be evacuated. No injuries and all employees accounted for.
— TN Valley Authority (@TVAnews) November 13, 2017
