What is "safety curtain"

n. a fireproof theater curtain to be dropped in case of fire

A safety curtain (or fire curtain in America) is a fire safety precaution used in large proscenium theatres. It is usually a heavy fibreglass or iron curtain located immediately behind the proscenium arch. Asbestos-based materials were originally used to manufacture the curtain, before the dangers of asbestos were discovered. The safety curtain is sometimes referred to as an iron in British theatres, regardless of the actual construction material.

Occupational safety and health regulations state that the safety curtain must be able to resist fire and thereby prevent (or at least hinder) fires starting on stage from spreading to the auditorium and the rest of the theatre, reducing injuries to audience members and members of staff.

The curtain is extremely heavy and therefore requires its own dedicated operating mechanisms. In an emergency, the stage manager can usually pull a lever backstage which will cause the curtain to fall rapidly into position. Alternatively, heat-sensitive components can be built into the rigging to automatically close this curtain in case of fire. Finally, it may be released electronically by a building's fire control system if any alarm box is operated. It can also be flown in and out, as regulations in some jurisdictions state that it must be shown to the audience, to prove its effective operation, for a certain amount of time during every performance. This usually occurs during the intermission.

In smaller theatres, a safety curtain is not usually required. Specifically, most United States building codes only require a fire curtain in theatres with a stage height of more than . The heavy, flame-retardant house tabs can provide some degree of fire separation.

In the UK, it is a requirement that a safety curtain must be fully down within the proscenium opening within 30 seconds of being released. In 1794 the Theatre Royal, Drury Lane became the first theatre to feature an iron safety curtain. Several other serious fires, notably that at the Theatre Royal, Exeter in 1887, led to the introduction of safety curtains on a wider scale.

Chicago's 1906 Iroquois Theatre fire resulted in over 600 deaths when theater's safety curtain got stuck midway down, along with other structural deficiencies in the building.