Product Data Lower and Upper Explosive Limits for Flammable Gases and Vapors (LEL/UEL) Printer-Friendly Page Gas LEL UEL 1,3-Butadiene 2  12  1-Butene 1.6  10  2,2-Dimethylpropane 1.4  7.5  Acetylene 2.5  80  Ammonia 15  28  Benzene 1.3  7.9  Butane 1.8  8.4  Butyl Acetate 1.4  8  Carbon Monoxide 12.5  74  CIS-2-Butene 1.6  9.7  Deuterium 4.9  75  Diborane 0.8  88  Dimethyl Ether 3.4  27  Dimethylamine 2.8  14.4  Ethane 3  12.4  Ethanol 3.3  19  Ethyl Acetate 2.2  11  Ethyl Benzene 1  6.7  Ethylene 2.7  36  Hexane 1.2  7.4  Hydrogen 4  75  Hydrogen Sulfide 4  44  Isobutane 1.8  8.4  Isobutylene 1.8  9.6  Methane 5  15.4  Methanol 6.7  36  Methyl Bromide 10  16  Methyl Ethyl Ketone 1.9  10  Methyl Mercaptan 3.9  21.8  Methylacetylene 1.7  11.7  Monoethylamine 3.5  14  Monomethylamine 4.9  20.7  n-Butanol 1.7  12  Oxide 3  100  Propane 2.1  9.5  Propylene 2.4  11  Toluene 1.2  7.1  Trans-2-Butene 1.8  9.7  Trimethylamine 2  11.6