NFPA 101(R), Life Safety Code(R), offers guidance to those designing egress paths.

Those designing and evaluating egress systems are often concerned about rooms or spaces from which the egress path doesn't directly lead to an exit access corridor. This arrangement is typically referred to by codes such as NFPA 101(R), Life Safety Code(R), as "egress through adjoining areas."

Recently, I was asked to evaluate such an egress path in a hospital's administrative area. This path, which provided two hospital employees with their only way out of the area, passed through a cashier space with a locked door. In accordance with Section 7.5.2.1 of NFPA 101, I recommended moving the employees' work space so they no longer had to pass through the locked area. Section 7.5.2.1 states that the doors in any rooms or space adjoining an egress path through which people have to pass must be unlocked. This requirement is consistent with the basic principles of egress: occupants must control their egress paths, and special knowledge, effort, tools, or keys should never be required to open any door in such a path.

Section 7.5.1.7 further restricts egress through adjoining areas by stating that such spaces may not be used as hazardous areas. If a storage room contains combustibles, for example, the egress path shouldn't pass through it.

This requirement is often misunderstood. Recently, I was asked whether the exit path from supervisors' offices in a manufacturing complex could pass through an adjacent industrial area, which some felt posed a higher hazard than the offices. A corridor between the offices and the industrial area wasn't a desirable option because it would reduce the supervisors' ability to monitor employees. But was one necessary?

The answer in this case was "no." Since the industrial area was the primary use of the building and the offices weren't, the industrial area couldn't be considered a hazardous area, and the offices' occupants could pass through it. The various egress requirements for the supervisors' offices were the same for every other area of the complex.

If the same industrial process were present in an office building, however, I may have required that the process area be identified as a hazardous area, which would've prohibited emergency evacuation through it. The primary egress requirements would be based on the hazards anticipated in a business occupancy, rather than those found in an industrial operation. Furthermore, there's a difference between permitting the supervisors of an industrial area to leave their offices through that area and allowing occupants of an office building to leave through an accessory repair area.

Accessory spaces

Section 7.5.1.7 of NFPA 101 also requires that the space through which egress is required be accessory to the space it serves. This means that the activity performed in the accessory space is related to the activity performed in the space from which individuals will evacuate and that it will be occupied at the same time. Such spaces include office or restaurant waiting areas, small offices adjacent to industrial or mercantile areas, and offices or storage rooms adjacent to classrooms.

For example, the egress path from my office passes through an administrative area before it reaches an exit access corridor. Since I often walk through this area, I'm familiar with its use and operation, and this familiarity makes the area an accessory space for my office. However,

it isn't an accessory space for other tenants in my building because they don't routinely pass through it and thus aren't familiar with what happens there. We could be in the process of replacing the carpet in that area, which would impede travel, and they would have no way of knowing that anything was amiss.

When egress is provided through an adjoining area, the occupant load of the area becomes cumulative. If the occupant load reaches 50 people, Section 7.2.1.4.2 says that the doors that serve those 50 people must swing in the direction of egress travel. In assembly occupancies with large occupant loads, latching doors serving the aggregate area through which all the occupants will pass in an evacuation must have panic hardware.

Finally, NFPA 101 allows egress paths to pass through several accessory areas if they meet the various egress arrangement requirements, such as common path of travel and remoteness from the suite. The exception is health care occupancies, in which the allowable distance to the door of a suite is reduced when the egress path passes through multiple intervening rooms-and only two intervening rooms are permitted. In most other occupancies, as many intervening rooms as possible are permitted, as long as the occupancy meets all other egress requirements.

In sum, then, NFPA 101 permits egress paths to pass through adjoining spaces, provided certain code requirements are met. As long as the paths are designed to meet Life Safety Code requirements, they'll provide a reasonable degree of safety.

FOR MORE INFORMATION ON NFPA 101(R), LIFE SAFETY CODE(R), CHECK OUT WWW.NFPA.ORG.