Some Facts, Misconceptions and Commentary About Egress and Exits

 

A short, distantly related preamble:  I’ve heard it said that déjà vu is simply a crossed circuit in the brain, where instead of parking the elapsing moment into short term memory, a synapse misfires and directs the sensory perceptions into long term memory.  In that same instant of storing the memory, there’s also an immediate sensation of remembering it.  So much for romantic notions expressed in French language.

 

 

exitno exit

 

With that in mind, I occasionally will be in the midst of clarifying something to someone about the building code or the zoning regulation or the canons of good design, or what have you, and I am suddenly awash with that sensation of déjà vu.  But really, it’s not quite déjà vu.  It’s more just the revisiting of a concept or principle that is coming up in a new particular set of circumstances, much as it has come up in many similar sets of circumstances over the span of many years.  It’s probably better described as “professional practice”.

I was discussing a project with someone recently, and this exact phenomenon occurred.  In this instance, I found myself explaining, in terms of the building code, that an “egress window” is not an exit, and an exit is not an “egress window”.  “Here I am again”, I thought.

I have discussed this topic many times, actually, with various people in various situations.  In all instances, my counterparts in conversation had gotten stuck on what is more or less a catch phrase of my industry.  Namely, the phrase “two-means-of-egress”.  It always rolls out as if it were one multi-syllabic word.  Where are your two-means-of-egress?  Every building needs two-means-of-egress, right?  Well, actually, not really.  And by the way, what exactly do you mean by “means of egress”?

The topic tends to come up in residential projects, both single family and multi-family, or in mixed use buildings where residential is one of the uses.  Discussions about egress from all use groups other than residential are somewhat more straight-forward, I find.  Mainly because for those other use groups, discussions about egress are not burdened with the term “egress window”.  I review this a bit further as item #1 in the list below of some miscellaneous facts on exits and egress (there are many more, depending on your situation):

  1. Though it is clearly wedged into our lexicon, the term “egress window” does not actually occur in the IBC or the IRC (International Building Code and International Residential Code – two model codes that form the basis of the State Building Code).   When people speak of “egress window”, what they really mean is “emergency escape and rescue opening”.  I feel that the use of the word “egress” with “window” charges the popular phrase with a misleading connotation that in turn leads people to some basic misconceptions.
  2. The criteria for code compliant emergency escape and rescue openings do not meet the criteria for a required exit.  In fact, not even nearly.  This is because those two things are different in nature.  One is an apple, the other an orange.  One is about the emergency extraction (on one’s own or with the assistance of a firefighter) of an individual occupant and the other is more about safe, orderly, organized egress of building occupants en mass.
  3. In terms of the building code, an exit is not a singular, static thing but rather is a system of interconnected things.  In fact, the code establishes that an exit is comprised of three distinct components:  the exit access, the exit, and the exit discharge.
  4. Generally speaking, an emergency escape and rescue opening is required in sleeping rooms of dwellings and in habitable spaces of basements in dwellings, though there are exceptions in certain particular circumstances.
  5. Generally speaking, and except where particular circumstances are present, emergency escape and rescue openings are required to have minimum clear openings (24” high and 20” wide) with a minimum net clear area (5.7 sf generally).  These criteria are not based on a person escaping through the clear opening, but rather on a firefighter in full equipment entering through the clear opening.  Dimensions of exit components, on the other hand, are influenced by factors such as the building’s occupant load, among others, making the design of an egress system potentially quite complex.
  6. Where two exits are required to be provided from the building, an emergency escape and rescue opening cannot under any circumstance serve as one of those exits (see #2 above).
  7. Under certain circumstances, most uses can occupy buildings where only one exit is required.  Those circumstances provide inherent safety features, such as limited building height and area, limited occupancy and limited distance of travel to the point of exit access within the building; those provisions are more generous where the building is equipped with an approved automatic sprinkler system.

Egress is so very important in the design of a building.  In the event of tragic circumstances, its design may mean the difference between life and death.  If climbing through the opening of that window gets you out of a burning house with your life, then really, who cares what it’s called.

Few things are so serious as a building that is on fire.  I once escaped a building on fire when I lived in New York City.  My mother once escaped her burning house by jumping from her second story bedroom window.  So I hope it doesn’t appear that I am splitting hairs and parsing something so critically significant as egress provisions in buildings.  Nonetheless, I feel that even in the dense gravity of a concept like egress, it is important for those involved in building projects to appreciate the code in its spirit and its nuance, to grasp it as it is intended, and not as our catch phrases would lead us to misconceive.

 

 

figure running

 

 

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