Urbana, IL — Urbana firefighters continue to investigate a gas leak that caused an explosion Monday at a privately owned dormitory on the University of Illinois campus.

Urbana Fire Chief Chuck Lauss said 56 students were evacuated from Hendrick House, 904 W. Green St., after the explosion at 9:22 p.m. No one was hurt.

An employee whom Lauss called “very blessed” was investigating the heavy gas smell in the mechanical room in the basement. He checked things out, then left to call the company that does heating, air conditioning and mechanical work for the dorm.

Lauss said the man had just stepped outside the building when he heard the explosion.

“He said it was probably about a minute,” Lauss said, adding that man was not hurt.

The explosion affected a small single-story building attached to the north side of Hendrick House at its rear dock.

“It blew the roof completely off of it,” the chief said.

The building houses a walk-in freezer. He estimated it to be about 24 feet square.

“There was heavy structural damage,” he said. “The steel trusses on the roof … have a lot of damage. It appears the walls are cracked and pushed out a bit.”

Lauss said the first firefighters arrived on scene just two minutes after getting the call.

There was no fire, but they also noticed the heavy odor of natural gas. He said residents were already evacuating. There was also debris from the damaged building, mostly in the parking lot on the dorm’s north side but some on Lincoln Avenue as well.

Hendrick House officials were able to relocate the residents to Daniels Hall across the street.

“Our crews’ focus was on what the issue was,” Lauss said. “They took the detection equipment in and noticed a heavy presence of natural gas on the north side of the building where the explosion happened.

“We called for our MABAS ventilation fan, which is a huge, huge fan that they pull on the back of a pickup truck,” he said, using the acronym for the Mutual Aid Box Alarm System. “We set that up on the south side of the building and started ventilation to get the gas moved out of the building.”

“We back it up to the front of the building and get it started and open limited amounts of the building,” the chief said. “That creates positive pressure and moves air out of the building much faster. We vented it for about an hour to 90 minutes and got to the point where we could get in.”

All 16 firefighters on shift plus the chief responded. Cornbelt firefighters brought the fan. The chief said the pre-planning and training the department routinely does paid off.

“They will look for areas to quickly evacuate people from and to,” he said of the pre-planning. “Our number-one priority is life safety and to get those residents out. They have an idea when they get there where they need to be.

“The firefighters, as usual, were extremely professional and caring with making sure everyone was evacuated and finding out what they needed to do,” he said. They were also able to shut down utilities immediately.

The Champaign-Urbana Mass Transit District sent a bus to help with moving the residents.

“We turned the building back to the owners about 2:15 (Tuesday) morning,” Lauss said, adding that they are “not even close” to completing the investigation.

Besides investigators from his department and the Office of the State Fire Marshal, Lauss said insurance officials are expected to have their inspectors try to figure out what happened and to see if there is structural damage to either of the two towers.

The dormitory can accommodate 364 students, according to its website.

“We will not be repopulating the building until the building has been thoroughly investigated and the cause of the leak has been taken care of,” according to a post on that site. “We will do our best to keep you and the students updated on the progress and make sure that everyone keeps safe during this.”

Lauss said residents were allowed in the building to get personal items Tuesday but will not be staying there until the problem is identified and resolved.