Someone asked me recently why distributors are still ordering swinging fire doors with a neutral pressure fire rating. I don’t know the answer to that, since the model codes have required positive pressure assemblies for many years. Here’s where the IBC states this requirement:
718.104.22.168 Side-hinged or pivoted swinging doors. Fire door assemblies with side-hinged and pivoted
swinging doors shall be tested in accordance with NFPA 252 or UL 10C. For tests conducted in accordance with NFPA 252, the fire test shall be conducted using the positive pressure method specified in the standard.
UL 10C is called the Standard for Positive Pressure Fire Tests of Door Assemblies – that’s pretty clear. NFPA 252 can be used for either a neutral pressure test or a positive pressure test, but the IBC states that the positive pressure method must be used. So where are neutral-pressure doors being installed? Do you know?
If you’re not familiar with the difference between neutral pressure and positive pressure fire testing, I just came across this video from Reeb Millwork and I think it’s a great explanation.