Seven fire trucks responded Thursday morning when a fire started during an experiment in the Engineering Research Building, that filled the building with smoke.
The fire began around 10:30 a.m. in the basement of the building, where the Pegasus Torodal Experiment is located. UW-Madison officials have yet to announce the extent of the damage.
\It's a plasma physics experiment,"" said Greg Garstka, an assistant scientist in the engineering physics department who is working on the experiment.
The experiment, which is related to fusion energy, has strict safety rules that do not allow anyone to enter the room while it is being conducted. When the fire began, the research team was conducting the experiment from another room.
""We were looking at it through closed-circuit TV and saw a fire,"" said Zeke Ungerberg, a UW-Madison graduate student in engineering physics who was among those conducting the experiment.
Garstka said that due to the nature of the experiment, there have been fires before. However, none have been this severe.
""We've had smaller explosions before, but this is the first one that's been this serious,"" Garstka said.
According to Jake Blanchard, an associate professor of engineering physics, the experiment involves capacitor banks that store a large amount of energy and release it all at once.
The fire began when a diode, or an oil-containing instrument that only allows current to flow in one direction, malfunctioned and allowed oil to leak. The oil, which was near a pressurized air line, ignited.
""One of the diodes failed, they're pretty sure, and they have oil in them,"" said Steffi Diem, a UW-Madison junior who is working on the experiment. ""The oil got hot enough [and] ignited and blew it's steam and there's a pressurized air line right by that, so we think that's what set the fire.""
Soon after the researchers saw the fire, their television cut out and the fire alarm sounded.
The fire itself was relatively small. Despite this, smoke quickly traveled from the basement to the top of the 14-story structure.
A Madison firefighter on the scene said that the fire was ""knocked down"" within half an hour, but firefighters remained in the building to clear smoke from the upper floors.
The large amount of smoke was difficult to get out of the building because there is little ventilation in the structure.
""They had to cut the power [in the basement] because we work with high voltage so there are no fans [and] no ventilation,"" Ungerberg said.
The Madison Fire Department had to bring in positive pressure fans to alleviate the problem.
Everyone in the building at the time was evacuated. Diem said the the researchers were allowed to return at approximately 2 p.m.
Damage in the building was confined to the basement.
