# Flour — Gas group, temperature class and autoignition temperature by substance

For Flour, classification system is IEC / ATEX; apparatus / gas group is IIIB; ignition temperature (c) is 490; dust layer ignition temperature (c) is 340, recorded from its source on 2026-08-06.

- **Substance:** Flour _(verified: appears in the quote below)_
- **Classification system:** IEC / ATEX _(our reading, not quoted from the source)_
- **Apparatus / gas group:** IIIB _(verified: appears in the quote below)_
- **Ignition temperature (C):** 490 _(verified: appears in the quote below)_
- **Dust layer ignition temperature (C):** 340 _(verified: appears in the quote below)_

## What the source says

> Flour | IIIB | 490 | 340

## Source

- https://www.e2s.com/guide-for-hazardous-areas/apparatus-groups-and-common-flammable-ga

Last verified: 2026-08-06. Review by: 2028-08-05.
Part of [Gas group, temperature class and autoignition temperature by substance](https://referencesource.org/hazardous-area-substance-classification/).