Classes in Dennison Hall were interrupted Tuesday afternoon when built-up smoke in the building caused the fire alarms to go off.
Fire alarms initially triggered at around 2:20 p.m. People were allowed to re-enter the building at about 3:00 p.m.
Firefighters exiting the building at around 2:45 p.m. said that there was an excess smoke buildup in an area of the building where welding was taking place.
Department of Public Safety spokeswoman Diane Brown confirmed that the origin of the smoke was from some welding being done in the basement by contract workers.
The smoke triggered the fire alarms, the firefighters said, and there was no fire in the building. Brown said there was no damage to the building.
DPS officers on the scene said that when the smoke alarm went off, the building was evacuated.
Students who were in the building at the time that the fire alarms went off reported a delay in the triggering of some of the fire alarms.
LSA senior Joel Williams, who was in the building, said that the smoke alarms in the classrooms failed to go off when students could hear the fire alarms ringing in the stairwells.
Robert Newman, an LSA senior, said students in his class were not evacuated until 15 to 20 minutes after they initially heard the fire alarms going off in the stairwells.
Brown said that in high-rise buildings, which Dennison qualifies as under the fire code, fire alarms only ring on the floor on which the alarm is manually pulled, on the floors immediately above and below that floor, and in the stairwells.
She said that most likely somebody smelled the fumes and pulled the alarm causing only those select alarms to ring. When DPS officers went through the building to find the source of the smoke, Brown said, they determined that additional floors should be evacuated, which is why the entire building was eventually evacuated.
Since there was no actual fire, there was nothing to activate the building’s entire fire alarm system, she said.
Brown said the fire alarm had last been tested in February.
Brown said that she had heard reports that some students ignored the fire alarms when they rang and continued what they were doing.
“When they hear a fire alarm they need to evacuate for their own safety and the safety of others,” she said.
LSA junior Matt Sisson said that a friend was taking an exam at the time the fire alarms triggered and that the exam had been postponed.