By Jake SpringThe Daily Northwestern
Students and faculty evacuated four North Campus buildings Wednesday after a suspected leak of a chemical that gives natural gas its smell, authorities said.
The Evanston Fire Department arrived at the Technological Institute at about 1:30 p.m. after responding to a call about a gas leak.
When firefighters arrived on the scene and smelled something similar to natural gas, they pulled the fire alarms and evacuated the building.
Cook Hall, the Francis Searle Building and the Pancoe Life Sciences Pavilion were also evacuated.
When no source was discovered and the smell disappeared, EFD reopened the buildings.
The release of the buildings back to students and staff was staggered, with Tech being released last at about 2:30 p.m.
The probable cause was a spill of the chemical mercaptan, which is added to natural gas to give it a noticeable scent, said Fire Chief Alan Berkowsky of EFD.
“The call came in as an odor investigation, the smell of natural gas,” he said. “Just a small drop of that chemical can give the impression of a large gas leak.”
After monitoring the buildings using gas detectors, no natural gas was found in the air. All evidence indicated a mercaptan spill rather than a gas leak, Berkowsky said.
“It dissipated pretty quickly,” he said. “Our meters didn’t pick up anything and no one was symptomatic.”
A “situation almost identical to this” occurred about six months ago and has further convinced Bukowski that the chemical spurred the incident, he said.
In April a beaker of mercaptan spilled in the Center for Nanofabrication and Molecular Self-Assembly, causing four North Campus buildings to be evacuated.
Wednesday’s incident follows less than a week after Tech was evacuated for an unrelated chemical explosion that injured two students.
Hundreds of students milled in the rain outside, not knowing whether their classes would be canceled, and many students left the scene.
The psychology course Human Sexuality began 30 minutes late because of the evacuation.
Fewer than half of the 347 students attended the class in the Ryan Family Auditorium in Tech.
“You are dedicated and faithful,” Psychology Professor J. Michael Bailey said, addressing the class. “Sorry about that, I didn’t do it.”
One Weinberg sophomore sat in a nearly empty lecture room not knowing whether his astronomy class would be held. He heard the alarm go off from his room in Foster House.
“When I got here, everyone had already evacuated,” Mark Duric said. “I didn’t know what was going on.”
Reach Jake Spring at [email protected].
