PITTSBURGH, Pa. — A natural gas leak caused an explosion that ripped open a University of Pittsburgh building and collapsed a portion of its roof on Jan. 20, 1977. Two people were killed and about 47 others were injured in the blast at Langley Hall.
Langley Hall’s lecture halls and laboratories were damaged by the blast, which occurred about 12:40 p.m. An estimated 160 students were in a physiology class in one of the lecture halls adjacent to the origin of the explosion and an undetermined number of other people were scattered throughout the building at the time.
Glass windows more than 75 feet away were blown out and buildings throughout Oakland were shaken, including the Cathedral of Learning, in which students on the sixth floor were watching President Jimmy Carter’s inauguration speech.
A strong odor immediately permeated the area, hindering first responders and causing numerous secondary injuries.
Carleen Curry, 35, a secretary from Pittsburgh and Patricia Hostetler, 20, a chemistry major from Donegal, were killed.
Hostetler’s boyfriend, psychology major Bob Cina, 21, had kissed her moments before the blast and became trapped under debris within sight of Hostetler’s body. Cina sustained multiple fractures in his back, but recovered. The couple were waiting to return notes to one of Cina’s classmates when the roof collapsed.
Curry was on the phone with a member of her family when the blast hit. She was killed instantly. Coroner Cyril Wecht later found methane present in Curry’s blood, which is a strong indicator of natural gas.
Initial reports put the death toll higher and officials were concerned more victims may have been trapped under tons of crumbled concrete. Heavy cranes were quickly brought to the scene to remove debris.
The disaster could have been much worse. Just 10 minutes before the blast, a psychology class full of 200 students had just been let out of the lecture hall immediately above the center of the explosion.
Thirty-five people were treated and released, four held for observation and six people were admitted to hospitals. A firefighter was reported to be in critical condition and two others suffered from gas inhalation.
Initially, natural gas had been ruled out as a cause by Pittsburgh’s Fire Chief, who said the odor was more like that of shoe polish. The building’s heat came from steam and none of the building’s labs were actively using gas lines at the time.
The odor was attributed to a toxic chemical called nitrobenzene that was used in the labs and thought early in the investigation to have been a factor. University of Pittsburgh chemists confirmed that the gas was responsible for the strong odor in the area after the explosion, but doubted it could have caused it, as it was not explosive.
Investigators for the State Public Utility Commission confirmed the likely cause when they found a break in a four-inch Equitable Gas line that also fed the Bunsen burners in the building’s labs. The line predated the structure and had been used for houses that used to be at that location. The branch line to Langley Halls’ labs was not damaged.
The explosion was centered on a crawl space underneath Room 221, a large lecture hall next to an electron microscope lab. Investigators also said Curry’s body was found along with cigarettes and matches in the ruins of an adjacent office. Adjoining buildings had “No Smoking” signs hastily posted as a precaution.
Langley Hall was completed in 1961 and named for Samuel Pierpont Langley, an astronomer and aviation pioneer. Langley was a former University of Pittsburgh professor and director of the Allegheny Observatory.
Following the explosion, Langley Hall was rebuilt and reopened in 1982.