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Building fire hazard class: A, B, C, D, E
Enter the total area and the areas of class A, B, C and D rooms. The tool tests each class in turn by area share and returns the class of the whole building.
Quick answer
The building is class C (Fire hazard).
Preliminary results
Building classC
Last-step share12.0%
| Step | Result | Basis |
|---|---|---|
| Test class AA = 0 m² = 0.0 % ≤ 5 % · ≤ 200 m² | No | SP 12.13130 §6 · QCVN 06:2022 ⚠ |
| Test class BA + B = 0 m² = 0.0 % ≤ 5 % · ≤ 200 m² | No | SP 12.13130 §6 · QCVN 06:2022 ⚠ |
| Test class CA + B + C = 1,200 m² = 12.0 % > 10 % | → Class C | SP 12.13130 §6 · QCVN 06:2022 ⚠ |
Sources and assumptions. Building class by share of class A–D room areas, SP 12.13130 section 6, referenced by QCVN 06:2022/BXD for production buildings and warehouses ⚠. ⚠ = code table value to be checked against the original standard. Preliminary results for material selection and budgeting; not a substitute for an approved fire protection design.
Building class rules
| Class | Hazard | Condition |
|---|---|---|
| A | Fire and explosion hazard | A rooms > 5 % or > 200 m² (sprinklered: exempt if ≤ 25 % and ≤ 1,000 m²) |
| B | Fire and explosion hazard | Not A; A + B rooms > 5 % or > 200 m² (sprinklered: ≤ 25 %, ≤ 1,000 m²) |
| C | Fire hazard | Not A, B; A + B + C > 5 % (10 % without A, B); sprinklered: ≤ 25 %, ≤ 3,500 m² |
| D | Moderate fire hazard | Not A, B, C; A + B + C + D > 5 % (sprinklered: ≤ 25 %, ≤ 5,000 m²) |
| E | Low fire hazard | None of the above |
Frequently asked questions
A 150 m² paint room in a 10,000 m² factory: which class?
A paint room is usually class B: 150 m² = 1.5 % and under 200 m², so not class B; continue with class C using A + B + C.
Why does building class matter?
With fire resistance it sets outdoor fire water, indoor hydrants, compartment size and separation distances.