TRANSCRIPT
How do occupants know where exits are located?
INTRODUCTION So, in this series we’ve introduced concepts on exits, exit access, exit discharge, and in our last two videos we talked on arrangement of exits and where we ideally have the exits located. The path to exits are marked by exit signs. Where exactly are exit signs required? What color does it need to be? Why do I sometimes see them on the floor? We’ll get into all of that in this segment. EXIT SIGNS So first, let’s start by defining what is an exit sign? It is a sign that is constantly illuminated in large letters indicating where exits are located. IBC requires the letters to be a minimum of 3/4” high with 2” wide letters. This sign may incorporate directional arrows to guide occupants in a certain direction. LOCATIONS REQUIRED (AT EXITS) Where are exit signs required? Well, in a lot of places. The exact number will depend on the size of the building and the configuration of the egress system. To start, let’s consider the exits. Hey! I know what an exit is. Good, then you were paying attention in the previous videos. In case you weren’t, refer back to the previous videos defining the different types of exits. Exit signs are required to be placed directly adjacent to exits. Usually, the exit sign is mounted on the wall or ceiling directly above the door to the exit or in the corridor in the field of vision of an approaching occupant, pointing at the door. Not only must exits be marked with exit signs but exit access must be too. IBC REQUIREMENTS In the IBC 2021 edition, the requirements for exit signs are located in Chapter 10, which establishes the means of egress requirements. Section 1013 of Chapter 10 establishes all of the requirements for Exit Signs. Specifically, section 1013.1 identifies where exit signs are required, with respect to exits and exit access, it provides the maximum distance between exit signs in corridors and provides exceptions for when exit signs are not required. NFPA 101 REQUIREMENTS In NFPA 101, the general requirements for exit signs are described in Section 7.10. Like other portions of NFPA 101, the requirement that establishes the need for exit signs is based on the individual occupancy chapters of 11 through 43. These will be found in the Chapter then the subsection X.2.10. For example, for New Business, the exit sign marking is required by 38.2.10 and shall be designed in accordance with Section 7.10. EXIT SIGNS EVERYWHERE? From the previous videos, we defined exit access as the path that an occupant takes to reach the exit. In that video we discussed that the exit access forms a large portion of the building footprint, so does that mean we need exit signs everywhere? Not necessarily. Let’s first discuss a prominent exception to the exit sign requirement. EXIT SIGN EXCEPTION: ONE EXIT OR EXIT ACCESS In the previous videos, we discussed that generally speaking, all rooms or spaces must have two exit access pathways (two ways out), excluding rooms with an occupant load less than 50. There are rooms with fewer than 50 occupants which do require two ways out because of their travel distance, called common path of travel, but we’ll get into that in a later video. Per the IBC, exit signs are not required in rooms or areas that require only one exit or exit access. This is stated explicitly in IBC Section 1013.1 Exception 1. In NFPA 101, exit signs can be omitted where the exit or way to reach the exit is readily apparent to occupants. This is listed in 7.10.1.5.1. But if the room only requires one way out, no exit signs are required per IBC. Why? Well, if the room only has one door, the way out is obvious. NFPA 101 would permit omitting the exit sign in this case. Now, there could be cases where a room only requires one way out but has more than one door, like an office with a small storage closet. In this case, the occupant of the office is likely familiar with their surroundings, and it would be clear to the occupant that the storage closet is not the way out. More than likely, an exit sign would not be required in this situation. A trickier example would be a business suite with fewer than 50 occupants. Maybe it has a few small offices, a storage room and a small conference room – all of these rooms open up into the lobby of the suite. Per IBC, if this entire suite is less than 50 people, then technically an exit sign is not required. However, NFPA 101 would still require the exit sign if the way out is not readily apparent. Even if a project is following IBC only (and not NFPA 101), it would be good practice to put one at the main entry/exit to this business suite, since there are many doors, and it may not be immediately obvious which one is the exit. So, exit signs are not required to mark the way out of small rooms where the way out is obvious but they’re required everywhere else? CORRIDOR EXAMPLE Well, let’s start the exit and work our way backwards. The exit itself must be marked. This will typically be a door, either a door to the exterior or a door to the interior exit stair. Of course, occupants have to get to this door. Where are they coming from? In a building with a system of corridors, it would be from the corridor. Could occupants approach from either direction down this corridor toward the exit? Then an exit sign must be provided to indicate the exit’s location from either direction of travel. More than likely the corridor isn’t a straight line, it probably has some turns. So exit signs must be provided to indicate that an occupant must turn to travel down the corridor which will lead to the exit. Are there any intervening doors the occupant must travel through to reach this corridor? Those must be provided with exit signs too. Eventually, we will have “walked backwards” to the room we start in. Also consider this in the “walking forwards” direction and assume there is an occupant in every room. Does that room require two exit access doors? If so, then both exit access doors must be provided with exit signs. Is the way out not obvious? Then exit signs might be required. Once the occupant has left that room, where do they go? What is their path to the nearest exit? If the occupant looks left down a corridor, then looks right down a corridor, how do they know which way they should go? There must be an exit sign directing them along their path. Any turn required would also require an exit sign pointing the occupant where to go. IBC Section 1013.1 and NFPA 101 Section 7.10.1.5.2 requires that the maximum distance between exit signs in a corridor is 100 feet, so in very long corridors, we must place additional exit signs to remind the occupant to continue traveling in the direction they are heading. When designing for exit signs, it’s helpful to remember the phrase “readily visible in any direction of egress travel.” Some would say “if there’s ever a point where an exit sign is not visible, you need to add more.” That’s not exactly what the code says, but it is helpful advice for someone just starting out. I would recommend drawing a travel path from every room and ensure that along that travel path, exit signs are provided to guide the occupant along every turn, and through every door they must travel until they have reached the exit. SIGNAGE REQUIREMENTS Does code require that the letters be red or green? You won’t find this written down in the model codes, IBC or NFPA 101. It comes down to local jurisdictional requirements. It’s best to check with your local AHJ on this one. SIGNS ON THE FLOOR? Why are they sometimes on the floor? In the IBC, this is a requirement for Residential, specifically R-1 occupancies. Floor-level exit signs are not required in other occupancies. The purpose of a floor level sign is that because smoke rises. If smoke were to block the ceiling mounted exit signs, the floor level signs would still be visible to occupants. Because occupants in R-1 occupancies might be sleeping and typically unfamiliar with their surroundings, this provides an additional level of safety in case the corridor was filled with smoke. But except in R-1 occupancies, these floor level signs aren’t required. In NFPA 101, floor proximity signs are only required in Special Amusement Buildings, which can be found in 12.4.7.7.2. Because these occupancies can contain mirrors, mazes or other features to intentionally distract occupants or obscure exits, this provides an additional level of safety in case of a delayed evacuation where smoke has filled the upper portion of a space and blocked the ceiling level exit sign. For NFPA 101 based projects, floor proximity signs are not required in other occupancies. SUMMARY So how do occupants know where exits are located? Exit signs guide occupants to the nearest exit. Exit signs are required immediately adjacent to all exits. Exit signs are also required along the exit access, the path an occupant is required to travel until they have reached the exit. Excluding small rooms which only require a single exit access door, exit signage must be provided from all rooms and spaces to guide the occupant until they have reached the exit. In the next segment we’ll work through some different situations on where exit signage needs to be located. Our next video topic will cover the number and size of the required exits. I’m Steven Barrett, this is MeyerFire University.
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