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Sprinkler temperature rating by ceiling temperature
Enter the highest temperature expected at the ceiling (sun-heated metal roofs, near ovens, boiler rooms). Get the rating class and bulb colour.
Quick answer
Hottest ceiling 35 °C: use a Ordinary rated sprinkler, 57 °C, orange bulb.
Preliminary results
Rating classOrdinary
Operating temperature57°C
Bulb colourorange
| Class | Max ceiling | Rating | Bulb colour |
|---|---|---|---|
| Ordinary | ≤ 38 °C | 57 °C / 68 °C | orange red |
| Intermediate | ≤ 66 °C | 79 °C / 93 °C | yellow green |
| High | ≤ 107 °C | 141 °C | blue |
| Extra high | ≤ 149 °C | 182 °C | mauve |
| Very extra high | ≤ 191 °C | 204 °C / 227 °C | black black |
| Ultra high | ≤ 246 °C | 260 °C | black |
Sources and assumptions. Temperature classes and bulb colours per NFPA 13; TCVN 7336:2021 requires the rating to exceed the maximum room temperature ⚠. ⚠ = 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.
Frequently asked questions
Which rating is used in offices and factories?
Ceilings below 38 °C use ordinary: 68 °C red bulb (most common) or 57 °C orange.
Do metal-roof factories need 79 °C sprinklers?
If the ceiling can exceed 38 °C (uninsulated roof, heat sources), use intermediate 79 °C yellow bulbs to avoid accidental operation.