1) Smoke Control does not have to be mechanical.
The NFPA 92 Standard for Atrium Smoke Control Design allows for non-mechanical means of controlling smoke such as doors and smoke or fire-rated curtains. Additionally, IBC requirements demand that glass enclosures minimize the total volume of smoke that the smoke control system must control.
What this means: You don’t have to use just fans, duct work, dampers, make-up air grills, etc. to meet the code requirements for atrium smoke control. There are other alternatives that will save money and be more efficient.
2) How long does the Smoke Control system need to work?
This is a very important question. The smoke control system must keep open areas in the atrium clear from smoke for 1.5 times the calculated egress time OR 20 minutes, whichever is less. For example, if your calculated egress time is 10 minutes your smoke control system would only need to work for 15.
3) Horizontal curtains don’t need to pass UL10C.
There is no requirement in the IBC code for an atrium horizontal curtain to pass UL10C (which would require a hose stream test).
4) You don’t have to get European textile-based solutions for smoke control.
Recently the Smoke Guard corporation in Boise, Idaho started manufacturing large fabric smoke and fire curtains which can be hidden architecturally. All of the products are made right here in the United States! In fact, I believe they are currently the only US company to completely make their product on US soil. There are obvious benefits to this, including shipping logistics and cost.
These four facts give architects a greater variety of options which may save their clients a lot of money.