by Thom Zaremba, shareholder at Roetzel & Andress

The most dreaded sound in any building should be the sound of fire or smoke alarms. Unfortunately, false alarms desensitize most of us to the potential seriousness of a real building fire, which, depending on fire loads and the operation of active fire suppression devices, can spread throughout a building at remarkable speed. If heat, oxygen and fuel are all present, a small flame can become a major building fire in less than 30 seconds.

Fire-rated glass can play an essential role in egress systems. Photo: TGP.

Knowing this, can buildings be made safer in the event of a fire? The answer is yes, and it lies in how the building’s means of egress are designed and constructed. Why? Because the means of egress is a building occupant’s only fire-protected, safe path out of a building. It’s safe because the exit portion of a means of egress system is normally a fire barrier made of fire-rated glass or other wall materials that will keep those passing through the exit safe from the flames, heat, smoke and hot gasses generated in a fire for about two hours.

So, what is the “means of egress?” The 2024 edition of the International Building Code (IBC) defines means of egress as “a continuous and unobstructed path of vertical and horizontal egress travel from any occupied portion of a building or structure to a public way. A means of egress consists of three separate and distinct parts: the exit access, the exit and the exit discharge.”

Of its three parts, exit access is arguably the most important, but it’s also the most elusive and overlooked when it comes to the safety of building occupants. Why? While the exit part of a means of egress system is constructed as a haven safe from fire with entrances clearly marked with lighted exit signs, in most cases, the exit access leading to the exit is not protected from fire or marked with signs that help with finding it.

The IBC defines exit access as “that portion of the means of egress system that leads from any occupied portion of an occupied building or structure to an exit.”

If you’re in an open building design, one without hallways or corridors, you’re basically on your own to find the exit access. The best way is to look around until you find an exit sign. Whatever path gets you there is your exit access. If you’re not in an open building, the corridors are usually the exit access routes, making them easier to find, but – remember – they’re not typically constructed to protect you from fire or smoke, so move through them quickly to reach the exit sign marking the entrance to the exit.

Buildings built before 2000 almost always had exit access corridors protected by one-hour fire-protection-rated glass or other fire-rated construction materials. However, the IBC has largely eliminated those fire-safe construction features, except in a very limited number of occupancies. This was done due to a policy known as sprinkler trade-offs. Under it, virtually all the fire-safe construction materials used to build exit access corridors leading to exits were eliminated, largely for economic reasons. It was thought that the cost of the materials used to protect exit access corridors from fire could, instead, be used to offset part of the cost of requiring automatic fire suppression devices, such as sprinklers.

Is the sprinkler trade-off policy a good thing or a bad thing? It depends. If the sprinkler system works properly and controls the fire until you have time to safely travel the distance necessary to get through the exit, access the exit and escape a building fire, that’s a good thing. However, if, for any reason, they fail to operate or control the fire … well … consider yourself lucky if the exit access in your building was built before the sprinkler trade-off policy, using fire-rated glass and other materials that will keep the fire from reaching you.

Last but not least, what is the exit discharge? It’s where the exit terminates, and you’re discharged safely into a public way outside the building, away from the fire.

Cheers! Here’s to making it safely through the elusive exit access to the fire-safe exit and out the exit discharge if those fire and smoke alarms turn out real!

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