By Dean Samet, CHSP
Smoke barriers serve a very important purpose, especially in healthcare occupancies. During a fire, protection of patients and staff is of paramount concern. If possible, patients intimate with the fire should be moved to safety immediately. For others, “defending patients in place” is often the first step in a number of actions established to keep patients out of harm’s way from a fire and the products of combustion. If and when it is determined that patients must be evacuated to an area of safe refuge, it is typically horizontally, on the same floor level, through smoke barriers to an adjacent smoke compartment. If the fire escalates, patients may have to be relocated from that smoke compartment or floor and moved vertically via stairs or elevators (if possible and permitted).
It is important to maintain smoke barriers according to their required ratings. Many building codes call for one-hour rated assemblies for new construction. The NFPA 101® Life Safety Code® also calls for required smoke barriers to be constructed with a fire resistance rating of not less than one hour in New Health Care Occupancies. The Life Safety Code® allows required smoke barriers in Existing Health Care Occupancies to be constructed with a fire resistance rating of not less than one-half hour. For hospitals accredited by The Joint Commission, there is a “code effective date” of March 1, 2003. TJC’s 2010 Life Safety chapter also addresses both new and existing healthcare occupancies. Buildings are considered existing occupancies if final plans for buildings, additions, renovations, or changes in occupancy were approved by the local authority having jurisdiction (AHJ) prior to March 1, 2003. Buildings with final plans approved after March 1, 2003 are considered new occupancies and will be surveyed as such.
One issue faced by many healthcare organizations is determining exactly at what rating they have to maintain their required smoke barriers, especially for older facilities. Often, existing construction documents and specifications or “as-built” drawings cannot be located nor can a determination be made on what the building codes called for at the time of construction way back when. If The Joint Commission was the only authority having jurisdiction, then the answer might lie with their “code effective date.” However, there are other AHJs to consider as well, such as the local or state fire marshal, or other local or state building officials.
When in doubt, a step-by-step process may be employed to determine the appropriate rating of the smoke barriers, such as:
• Refer to original construction documents/specifications and as-built drawings if possible;
• Contact the various AHJs, state or local building officials to determine what their requirements were at the time of construction;
• Contact the architect or architectural firm of record;
• Identify hospital-designated ratings painted or stenciled on the barriers; and,
• As a last resort, perform a “destructive test” to determine the barrier’s construction and assembly rating.
Once it has been determined what a smoke barrier’s rating should be, then it is possible to choose the correct materials for sealing penetrations and joints. For smoke barriers with a one-half hour rating, any penetrations and joints should be sealed with a product that is capable of resisting the passage of smoke, e.g., properly applied drywall joint compound, plaster, or other such material that is consistent with the composition of the wall. Because there is a fire resistance rating, it is required that both sides of the barrier be sealed, not just one, in order to maintain the rating of the wall assembly. For smoke barriers with a one-hour rating, any penetrations and joints should be sealed with a product that is capable of maintaining the fire resistance rating of the barrier using an appropriately rated fire caulk or fire stop system. Again, both sides of the barrier should be sealed. At no time should “insulating foam” that is not designed or rated for use as a smoke stop material be used to seal penetrations in a smoke barrier.
In the May 2008 Environment of Care® News, Volume 11, Issue 5, George Mills of The Joint Commission’s Standards Interpretation Group, stated that existing firestop applications are acceptable and do not have to be removed or replaced as long as they were installed according to original design specifications and are currently in satisfactory condition. He goes on to say that this does not apply to firestop applications that are not in good condition or “if the firestop is cracking or compromised in some other way, the organization needs to remove it and repair the barrier using current technology.” He adds that “…if the original material (which would not be compliant with today’s systems) is removed, it is not to be replaced. Instead, the penetration(s) should be repaired using current technology. This does not apply to systems that are designed to be removed and reinserted, such as firestop pillows or reusable putties.”
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