Defining the level of safety intended by the Life Safety Code
NFPA Journal®, July/August 2011
NFPA 101®, Life Safety Code®, is one of the few codes that provides a quantitative goal statement accompanied by a related set of objectives that, taken together, state the level of safety the code is trying to achieve. Most codes simply provide a plethora of requirements without necessarily defining the level of safety that compliance will accomplish. Understanding the level of safety the code is trying to achieve can help users focus on the intended goal, result in a more thorough application of its requirements, and help when judging an equivalency.
Section 4.1.1 states, “A goal of this Code is to provide an environment for the occupants that is reasonably safe from fire by the following means: (1) Protection of occupants not intimate with the initial fire development; (2) Improvement of the survivability of occupants intimate with the initial fire development.”
The first item intends that occupants of the building who are not intimate with the initial fire development will have enough time to evacuate from the fire area or relocate before the fire threatens them. This may be done by several means, including a fire alarm system to alert them, sprinklers to control the fire, controlled combustibility of interior finishes to reduce the speed of fire development, and adequate means of egress for the occupants to quickly leave the building if necessary.
The second item is a bit more interesting. “Intimate with the initial fire development” means that the person is so close to fire ignition that the developing fire could directly affect them. This may include direct contact with flames, radiant heat, or products of combustion. The code says the requirements may not absolutely protect anyone intimate with the fire, but may improve their chances of survival.
A hypothetical situation illustrates how this might work. A gentleman on a business trip has too much to drink one evening and returns to his hotel room. He sits on the edge of the bed and tries to light a cigarette with a match. He passes out as he strikes the match, which falls on the bed and causes the bed linens to smolder. The smoke alarm in his room activates to alert him, but he doesn’t hear it because he’s passed out. The smoldering fire eventually erupts into flames and becomes large enough to activate a sprinkler in the room, which causes the alarm system to sound throughout the hotel. Occupants not intimate with the initial fire development — that is, those in other rooms — are alerted and able to evacuate safely.
Whether the sprinkler activation in the room is enough to rouse the passed-out gentleman is anybody’s guess, but the code did provide reasonable measures to protect him and improve his chances of survival, even though he was intimate with the ignition. The activation of the smoke alarm was designed to alert him to the smoldering fire, and the sprinkler system was designed to control the fire and improve the chance of maintaining a tenable environment in the room.
Two additional goals found in Sections 4.1.2 and 4.1.3 of the code are to provide life safety during emergencies and reasonably safe emergency and non-emergency crowd movement.
Because the goal of the code is clearly stated, the code’s requirements can be better understood and more effectively applied.
Chip Carson, P.E., is president of Carson Associates, Inc., a fire engineering and code consultancy. He is a former member of NFPA's Board of Directors.