Bosun's chair

A bosun's chair (or boatswain's chair) is a device used to suspend a person from a rope to perform work aloft. Originally just a short plank or swath of heavy canvas, many modern bosun's chairs incorporate safety devices similar to those found in rock climbing harnesses.

In addition to the maritime applications they were developed for, bosun's chairs are also used for working at height in various maintenance industries. In commercial window cleaning, the term bosun's chair describes devices suspended from rope and equipped with seatboards, such as descent-only controlled descent apparatuses (CDAs).

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