Choosing the best safety measures for your building’s vertical exit enclosures (referred to here as “enclosures”) is key to preventing injuries and casualties during evacuations, tragedies that often result in lawsuits. To protect themselves and their building occupants against tragic evacuation scenarios, concerned building owners across the U.S. follow the safety measures for enclosures set forth in the International Building Code (IBC) and the International Fire Code (IFC), which regulate the construction quality, structural stability, and egress safety of commercial and residential R1 buildings that feature occupancy above 75 feet from the lowest level of fire vehicle access.
A version of the IBC, which regulates new construction, has been adopted by all 50 states, and a version of the IFC, which regulates new and existing construction, has been adopted by at least 42 states, making them the most followed building codes in the U.S. To understand why the codes’ egress guidelines for enclosures are critical to evacuation safety, it helps to understand the pitfalls of the safety measures that they replace: backup lighting and reflective safety signage.
Luminescent Safety Measures Vs. Traditional Ones
The codes require that enclosures contain the following implements to ensure the evacuation safety during low visibility:
• Luminescent egress markings, which are applied to the leading edges of stairs and landings, handrails and their extensions, the perimeter of landing areas, potential obstacles, and the doorframes and hardware of exit leading doors; and
• Luminescent safety signs, particularly running man signs, which are placed on exit leading doors; fire exit signs, which are placed at building exits; and floor identification signs, which feature the following information to inform evacuees of their location and the direction of building exits: identification of the stair or ramp, floor level (also in Braille), total number of floors in the enclosure, and the level of and direction toward the exit.
Instead of electricity-free, maintenance-free luminescent signs and markings, enclosures traditionally contain backup lighting and reflective signs, a scenario that requires the lighting to work as expected in order to illuminate the signage. Unfortunately, backup lighting has two weaknesses that could compromise its effectiveness: it’s radiance can get lost in smoke and heavy dust, and it fails if emergency generators fail, as happened during the 1993 World Trade Center bombing.
Such a failure means that building occupants traverse stairwells in the dark, unable to locate critical signage that informs them of their location and how to reach exits. Due to the photoluminescence of IFC and IBC approved luminous egress systems, this situation never happens when your stairwells meet the codes’ guidelines. Instead of evacuations being characterized by panic and egress jams, the guidelines help to insure that they happen with efficiency and expedience.