Codes: Accessible Means of Egress (MOE)
When the first accessibility standards were developed (i.e. ANSI – A117.1), there were no provisions for accessible means of egress. The primary focus was to allow the disabled to enter and use a building. It may have been assumed that if you can enter, one could leave, but the approach is not the same. The philosophy, at least in high-rise buildings, has been to notify the floor below and two floors above the floor of incident. The fire alarm system does not sound a total building signal for evacuation. Once a signal has been initiated, occupants should evacuate using the MOE system within the building. Elevators have been, for the longest of time, signed to state “Do not use in an emergency.” This has all changed since 9/11.
So when an evacuation signal is initiated, what does a disabled person need to do?
Although Chapter 11A and B are not changing, there are other sections of the Code in the IBC which affect disabled access. Exiting requirements will remain in Chapter 10, but will also include IBC requirements for means of egress (MOE) for the disabled.
Under the 2015 IBC, the following are considered accessible means of egress elements:
• Elevators, Section 1009.2.1
• Areas of refuge, Section 1009.6
• Horizontal exits, Section 1026
Section 1009.2.1 of the 2015 IBC and 2016 CBC, requires buildings with accessible floors located four or more stories above or below the level of discharge that at least one accessible means of egress be by elevator. Additionally, elevator access is required to be associated with an area of refuge or a horizontal exit. Under the CBC and the ADA, areas of refuge are seldom incorporated into the design because buildings have been monitored by automatic sprinkler systems. The area of refuge will be required either within a stair enclosure, as shown in the illustration from the IBC Commentary, or an area that provides direct access to a stair or accessible elevator. Buildings and floors with sprinklers and a horizontal exit would be exempt from the requirements for areas of refuge. Although the activation of sprinklers allows time for occupants to exit a building, sprinklers alone do not provide equal facilitation for all occupants. A sprinkler system may limit the growth and spread of a fire, but smoke may continue to be generated and move through the building.
Although areas of refuge and horizontal exits do provide an additional protection from products of combustion (smoke and heat).
An important point that Kerwin mentions is the idea of equivalency. When we create an area of refuge, imagine the experience of a person using a wheelchair, in an emergency, being “trapped” in that enclosure while everyone escapes past, leaving them behind. Even though the Area of Refuge is a relatively safe spot, getting to the public way is better.
A horizontal exit is a more equitable solution; everyone exits together to a fire-separated portion of the building. I find lots of architects don’t know exactly what a horizontal exit is, so certainly few laypeople do. And Kerwin is right that they are not well signed.
Although you can’t always avoid an area of refuge, I encourage you to first try hard to exit everyone directly to grade. Establish this in your earliest diagrams of your project, and it will be easier to incorporate. As a second-best option, use horizontal exits that are well-signed. You may also find other advantages, such as reduction of the number of required exit stairs, when you incorporate horizontal exits. But I think the biggest benefit is that you’ll be treating your building users more equitably.