When it comes to fire and smoke protection in ambulatory healthcare facilities, the terms "fire wall," "fire barrier," "fire partition," "smoke barrier," and "smoke partition" can be confusing. This post aims to clarify the distinctions between these assemblies and provide guidance on their appropriate use.
Fire Walls: The Ultimate Protection
Fire walls are the most restrictive of all fire-resistant assemblies. They extend continuously from the foundation, through all floors, to or through the roof, and have the structural stability when there is a fire to allow collapse of the structure on either side without collapse of the wall itself. They are designed to separate buildings, for instance on a lot line, or major sections of a building when the building exceeds height and area limitations. Fire walls usually have 2-4 hour fire resistance ratings and are constructed of non-combustible materials. Penetrations in fire walls, and all fire rated assemblies, are required to be protected with approved assemblies, such as labeled doors, appropriate dampers, and tested fire stopping assemblies, and must meet other code requirements.
Fire Barriers: A Strong Line of Defense
Fire barriers are less restrictive than fire walls but still provide significant fire protection. They are used to separate areas within a building, such as different occupancies and fire areas, and to enclose exits, egress stairs, mechanical shafts, and areas with hazardous contents. Fire barriers have a fire resistance rating of at least 1 hour and can be constructed of materials allowed by the Construction Type of the building. They extend from the top of the floor below through the ceiling to the underside of the floor or roof deck above.
Fire Partitions: Dividing the Space
Fire partitions are the least restrictive of the three fire-resistant wall types. They typically have a fire resistance rating of at least 1 hour are used to slow the spread of fire to allow more time for occupants to exit the building. In typical buildings, for instance, they are used to separate dwelling units, tenant spaces in malls, corridors, and elevator lobbies.
Smoke Barriers: Controlling Smoke Movement
Smoke barriers are considered a continuous membrane that is designed to restrict the movement of smoke. They are not necessarily required to have a fire rating, though in some cases they do, such as when they are used to subdivide an ambulatory healthcare occupancy into smoke compartments. Smoke barriers should be continuous from the top of the floor below to the underside of the floor or roof deck above, from outside wall to outside wall, including continuity through interstitial spaces, like ceilings, attics, or crawl spaces.
Smoke Partitions: Containing Smoke Locally
Smoke partitions are also designed to limit the movement of smoke, but they provide less protection than smoke barriers, and generally are not required to have a fire rating. Smoke partitions should be continuous from the floor to the underside of the floor or roof deck above, or to the underside of a ceiling where it is constructed to limit the transfer of smoke. The space around penetrating items in a smoke partition do not need to be fire stopped like they would in a fire rated assembly, but must be sealed to prevent the passage of smoke.
Where to Use Each Assembly in Ambulatory Healthcare Facilities
Since building codes differ by location, it is important to check the specifics of the code in force at the time and location where your facility is being built.
Identifying Rated Walls
The codes now require that fire walls, fire barriers, fire partitions, smoke barriers, and smoke partitions be permanently identified with stencils or labels above ceilings. This has been a source of great confusion in the field regarding the form these signs should take and message they should convey.
The code requires signs with lettering not less than 3 inches in height with a minimum 3/8-inch stroke in a contrasting color located at intervals of not greater than 30 feet apart. The wording, “FIRE AND/OR SMOKE BARRIER—PROTECT ALL OPENINGS,” is the suggested message. To further avoid confusion, we typically ask the applicator to include the fire rating of the assembly (e.g. 1 hour) as well as the specific type of assemble (i.e. fire wall vs. fire barrier vs. smoke barrier, etc.). Further markings, for instance a line where a specific assembly begins or ends, or where an assembly is covered by furring, can be helpful.
By understanding the differences between these fire-resistant assemblies and their appropriate applications, architects, builders, owners, and inspectors can ensure that ambulatory healthcare facilities meet the necessary fire safety standards and provide a safe environment for patients, staff, and visitors. Contact us at Hardaway|Sziabowski Architects if we can help with you with your ambulatory healthcare facility needs. www.hsarchitecture.com