The Pittsburgh gasometer explosion, or Equitable Gas

EQT

EQT Partners is a private equity firm with approximately €13 billion in equity capital. Founded in 1994 by Investor AB, EQT Partners manages, through holding companies, numerous funds under the EQT banner. The company employs more than 220 people, of which are approximately 120 investment...

 explosion, was a bizarre accident that took place in Pittsburgh, Pennsylvania

Pennsylvania

The Commonwealth of Pennsylvania is a U.S. state that is located in the Northeastern and Mid-Atlantic regions of the United States. The state borders Delaware and Maryland to the south, West Virginia to the southwest, Ohio to the west, New York and Ontario, Canada, to the north, and New Jersey to...

 on the morning of November 14, 1927. A huge cylindrical gasometer

Gasometer

A gas holder is a large container where natural gas or town gas is stored near atmospheric pressure at ambient temperatures. The volume of the container follows the quantity of stored gas, with pressure coming from the weight of a movable cap...

, the largest in the world at that time, developed a leak, and repairmen were sent to fix it. The repairmen used an open flame blowtorch to find the leak. This turned out to be a serious mistake. The leak was found, but the tank full of natural gas then floated into the air like a balloon

Balloon

A balloon is an inflatable flexible bag filled with a gas, such as helium, hydrogen, nitrous oxide, oxygen, or air. Modern balloons can be made from materials such as rubber, latex, polychloroprene, or a nylon fabric, while some early balloons were made of dried animal bladders, such as the pig...

and exploded, causing a rain of fire and metal over a one mile radius. 28 people were killed and hundreds were injured.