Crash bar

A crash bar (also known as a panic bar, exit device,panic device, or a push bar) is a type of door handle that permits opening the door quickly during emergency conditions. The mechanism consists of a spring-loaded metal bar fixed horizontally to the inside of an outward-opening door. When the lever is either pushed or depressed, it activates a mechanism which unlatches the door, allowing occupants quickly exit the building.

Doors fitted with crash bars are commonly used in commercial and other public buildings, and are mandated by some fire safety standards. They are sometimes intended solely for emergency use, but in many buildings the crash bar functions as the primary mechanism for opening a door in normal circumstances as well.

Following the events of the Victoria Hall disaster in Sunderland, England in 1883 in which 183 children died because a door had been bolted at the bottom of a stairwell, the British government began legal moves to enforce minimum standards for building safety. This slowly led to the legal requirement that venues must have a minimum number of outward opening doors as well as locks which could be opened from the inside. Motivated by the Sunderland disaster, Robert Alexander Briggs (1868 - 1963) invented the panic bolt which was granted a UK patent on 13th August 1892.

However these moves were not globally copied. For example, in the United States, 605 people died in the Iroquois Theater Fire in Chicago in December 1903 because iron gates blocked exits. Five years later 174 people in Ohio died in the Collinwood school fire, which led to a national outcry in the U.S. for greater fire safety in buildings.

By the end of the 20th century, most countries had building codes (or regulations) which require all public buildings have a minimum number of fire and emergency exits. Crash bars are fitted to these types of doors because they are proven to save lives in the event of human stampedes. Panic can often occur during mass building evacuations caused by fires or explosions.

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