How many times have you seen evacuation diagrams posted on walls, with a route marked “primary egress route”? Think about it: What is a primary egress route? How does someone making a plan predict the type of emergency and where that emergency condition is going to be located? Is there really such thing as a “primary” egress route?
The short answer is no — NFPA 101®, Life Safety Code®, does not address a “primary” egress route. All egress routes are primary routes, and occupants should know where all of the exits are located.
The code generally requires two exits remote from each other in buildings; if one is blocked by fire or for some other reason, occupants still have another way out of the building. Section 4.7 requires that egress and relocation drills be varied to simulate an actual emergency. If occupants are instructed that there is a primary egress route and the drill is conducted the same way every time using that route, they may not be aware of the other egress routes and options available in an emergency.
Evacuation diagrams can be of great value, and there are several important features they should include. Above all, evacuation diagrams should be simple — remember, these are tools designed to help people get out of buildings as quickly as possible, not plans to show the location of all building features. The plans should include major features of the building, such as elevators, to help people orient themselves. But the location of sprinkler valves, smoke control equipment, or other fire protection equipment is not important to the occupants who only want to know where the exits are located.
Some people can get their bearings with just a quick look at a map, while others may have difficulty, which is why the plans should include a “you are here” indicator to help people quickly orient themselves. The plans may include assembly points so occupants know where they should go after they have left the building. Major landmarks outside the building, such as street intersections, can further help occupants orient themselves.
In the Life Safety Code, the requirements for where an evacuation diagram is required are located in the “Marking of Means of Egress” section within each occupancy chapter. Only assembly occupancies require a posted evacuation plan. Hotels require a “floor diagram reflecting the actual floor arrangement, exit locations, and room identification” to be posted on the back of or adjacent to the guest room door. That requirement is ocated in the “Operating Features” section of Chapters 28 and 29.
The Life Safety Code says that, where a posted evacuation diagram is required, the diagram should include certain features. (Note that this requirement is located in the section that addresses egress marking in Chapter 7.) Those features include a floor diagram that reflects the actual floor arrangement, including exit locations. The diagram should correspond with the perspective of the person viewing it. How many times have you been confused by a posted floor diagram until you finally figured out that you would need to be standing on your head for the diagram to be correct?
Evacuation diagrams are certainly a good idea, provided they clearly and simply show occupants all of the choices available for evacuation. In an emergency, the primary egress is the one that gets you out of the building quickly and safely.
Chip Carson, P.E., is president of Carson Associates, Inc. a fire engineering and code consultancy.