Lower flammable limit (LEL) or the lower explosive limit is the minimum concentration of vapour or gas in air above which propagation of flame does not occur on contact with a source of ignition. The mixture is said to be too lean.
Generalic, Eni. "Lower flammable limit." Croatian-English Chemistry Dictionary & Glossary. 29 June 2022. KTF-Split. {Date of access}. <https://glossary.periodni.com>.
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