Steel Column Fire Rating Calculator

Calculate the fire rating of a steel column based on section properties, loading, and protection per Eurocode EN 1993-1-2 and AISC

Input Parameters

Results

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Estimated Fire Rating
min
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Time to Critical Temp
min
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Temperature at 60 min
C
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Temperature at 120 min
C
Note: Section factor Hp/A is heated perimeter divided by cross-section area. Lower utilization factors allow higher critical temperatures. Unprotected steel columns typically achieve 15-20 minutes fire rating. Protected steel can achieve 1-4 hours depending on insulation.

Reference

Eurocode EN 1993-1-2 / AISC (ASCE/SFPE 29) ISO 834 fire curve: Tf = 20 + 345*log10(8t+1) Protected steel: dTs/dt = (Hp/A)*h_eff*(Tf-Ts)/(rho*c) h_eff = 1/(1/h_ext + dp/kp) Critical temperature: Tcrit ~ 550C (mu=0.5) Higher utilization (mu) = lower critical temperature kp values: spray=0.12, board=0.17, gypsum=0.20 W/mK