Flashpoint
The lowest temperature at which a liquid gives off enough vapor to form an ignitable mixture with air near its surface.
Definition, in the source's words
29 CFR 1910.106(a)(14)(opens ecfr.gov in a new tab)“Flashpoint means the minimum temperature at which a liquid gives off vapor within a test vessel in sufficient concentration to form an ignitable mixture with air near the surface of the liquid, and shall be determined as follows:”
What it means
Flashpoint, with boiling point, sets a flammable liquid's category under 1910.106 and HazCom. The lower the flashpoint, the easier the liquid is to ignite at room temperature.
Example
A liquid with a flashpoint of 50°F gives off ignitable vapor in an unheated shop in spring. A liquid with a flashpoint of 180°F won't, unless it's heated.
Where it appears on the exam
ASP: ASP11 Domain 4, Fire Prevention and Protection
Practice: Flammable Liquids
CHST: CHST5 Domain 2, Emergency Preparedness, Incident Investigation, and Response
Questions
- Is flashpoint the same as autoignition temperature?
- No. At the flashpoint, vapor can be ignited by a source such as a spark. Autoignition temperature is where a material ignites with no ignition source, and it's much higher.
Related
Checked 2026-10-16. Spot a problem? Email hello@passcited.com.