Flash Point & Flammability
Look up the closed-cup flash point of a common solvent and read its GHS flammable-liquid category, or enter measured flash and boiling points to classify any liquid.
How to use this tool
Find how easily a liquid catches fire and which GHS flammability category it falls in, the basis for its label, storage and shipping rules. Pick a solvent or type your own measured values.
What to enter
- Solvent: choose one to auto-fill reference values, or pick "Custom" to enter your own.
- Flash point: the lowest temperature at which the liquid gives off enough vapour to ignite, closed-cup, in °C. Lower means more dangerous.
- Boiling point: optional, °C. Only needed to separate the most volatile Category 1 (bp ≤ 35 °C) from Category 2.
Reading the result
You get the GHS flammable-liquid category: Category 1–2 (flash < 23 °C) are the most hazardous, Category 3 (23–60 °C), Category 4 (60–93 °C, combustible). This is a classification aid, not a predictor, always confirm against the actual product SDS.
Worked example
Ethanol, flash point 13 °C, boiling point 78.4 °C, classifies as GHS flammable liquid Category 2.
Liquid
Classification
Methodology
GHS classifies flammable liquids by closed-cup flash point and initial boiling point: Category 1 flash point < 23 °C and boiling point ≤ 35 °C; Category 2 flash point < 23 °C and boiling point > 35 °C; Category 3 flash point 23–60 °C; Category 4 flash point 60–93 °C (combustible). Above 93 °C is not classified as a flammable liquid.
Sources
- Reference flash and boiling points from the CRC Handbook and supplier safety data sheets.
- Category cut-offs from the UN GHS (Rev. 9), Chapter 2.6.
Known limits
- This is a lookup and classification aid, not a predictor. Always confirm against the actual product SDS; flash point varies with purity, water content and method (closed vs. open cup).
- Mixtures can flash below the lowest-boiling component's value. Test formulated products experimentally.