These terms are used every day in a skilled nursing facility, and sometimes interchangeably. However, they have different meanings. In fact, “smoke wall” is not even a term used in any code or standard that Florida or CMS has adopted.
Instead, “smoke barrier” is the accepted term and, according to NFPA 101 Chapter 8, has specific requirements. NFPA 101, 2012 edition, 220.127.116.11 and 18.104.22.168 say:
22.214.171.124 Smoke barriers required by this Code shall be continuous from an outside wall to an outside wall, from a floor to a floor, or from a smoke barrier to a smoke barrier, or by use of a combination thereof.
126.96.36.199 Smoke barriers shall be continuous through all concealed spaces, such as those found above a ceiling, including interstitial spaces.
The requirements for “continuity” or “continuous” barriers of 188.8.131.52 and 184.108.40.206 are fundamental conditions of a smoke barrier, and key elements in their construction and utilization.
Openings are a consideration
Smoke barriers and fire barriers are often constructed in the same manner, so what makes one barrier a smoke barrier and the other a fire barrier?
The determination is made by how the openings in the barrier are protected. The most common opening in a barrier is the door. The type of door that is installed in a barrier determines whether it is a smoke barrier or fire barrier.
Take for example a wall that is constructed of a 5/8” layer of drywall, studs, and another layer of 5/8” drywall. The wall goes from the floor through the ceiling all the way to the roof, and it runs from outside wall to outside wall of the facility. This makes for a barrier with a 1-hour fire resistance rating, and the door will determine whether it is a smoke barrier or a fire barrier.
If a positive latching door with a 45-minute fire protection rating is installed in the barrier, it will be a one-hour fire barrier. If a non-latching door with a 20-minute fire protection rating is installed in the barrier, it will be a one-hour a smoke barrier.
The door could also have no label indicating a fire protection rating, but if it is a door such as a 1 ¾” solid wood core door, it too will make the barrier a one-hour smoke barrier. This option is allowed because of NFPA 101 (2012 edition) 220.127.116.11(3). While barriers can have other openings such as windows, the easiest way to determine if the wall is a smoke or fire barrier is by its door(s).
In another example, let’s imagine a wall constructed of cinder blocks (CMUs); the wall runs from floor to roof and from outside wall to outside wall. This construction would create a barrier giving us a two-hour fire resistance rating. If we want to create a fire barrier, we would install a door with a 1.5-hour fire protection rating. There is a code allowance though that calls for installation of a non-latching door with a 20-minute fire protection rating which creates a one-hour smoke barrier.
NFPA 101 (2012 edition) 8.3.5 says:
A fire barrier shall be permitted to be used as a smoke barrier, provided that it meets the requirements of Section 8.5.
In this case, life safety drawings and barrier stenciling should reflect “one-hour smoke barrier”, but it is compliant with the Life Safety Code to have a smoke barrier with the higher level of fire barrier construction.
Understanding the construction and purpose of walls and barriers throughout your building(s) is central to maintaining their integrity against smoke and/or fire penetration and remains the single most important responsibility in life safety.