A chemical reactant explosion at Sisler Hall seriously injured a student and shut down traffic around 5:45 p.m. Wednesday, and authorities said the building will be closed all day today.
Gainesville Fire Rescue Department Chief Gene Prince said a student, whose name was not released, was working alone in a lab on the second floor "under a protective hood" when the explosion occurred.
Paramedics transported the student to Shands at UF in serious condition to be treated for burns.
Firefighter Andrew Marsh, 25, was one of the first to enter the building. He suffered minor burns to his eyes and face and was later released in good condition.
After the explosion, a GFR hazardous materials unit set up a makeshift bathing station in front of Sisler Hall where the team hosed people down outside the building. Police blocked off the surrounding traffic area, which created a backlog of about seven city buses waiting to pass the corner of Union Road and Buckman Drive.
According to GFR, one of the known agents involved in the research is sodium azide, a chemical found in some rocket propellants and car airbags.
The Centers for Disease Control and Prevention identifies sodium azide as a potentially deadly chemical that, when involved in an explosion, can cause burns and expose people to toxic gas.
Brittany Garner, a 19-year-old psychology sophomore, was in a group of students who waited on the corner and found out her General Chemistry class was canceled.
"It has to be an upper-level class," she said, "because our labs don't start until next week."
Officials remained at the scene for more than four hours. Sisler Hall will remain closed for at least 24 hours pending an investigation, according to GFR and GPD.
A firefighter hoses down Union Road after a chemical reactant explosion at Sisler Hall on Wednesday evening.
A Gainesville Fire Rescue Department worker stands in front of a fire engine after hosing down Union Road.
A self-contained breathing apparatus, used by firemen to prevent the inhalation of contaminated air, sits on the ground ready to be used for entry into Sisler Hall.
Gainesville Fire Rescue workers don hazardous materials suits in preparation for entering Sisler Hall on Wednesday night.
UF students watch as Gainesville Fire Rescue Chief Gene Prince is interviewed about the chemical explosion at Sisler Hall on Wednesday.