Quid CREPITUS-Probatur Level AT4 Mean?

A: Propane gas exemplum Class A ambitibus.

Classis et Level	Ignitio Temperature et Group
-	T1	T2	T3	T4	T5	T6
-	T＞450	450≥T＞300	300≥T＞200	200≥T＞135	135≥T＞100	100≥T＞85
ego	Methane
IIA	Ethane, Propane, Acetone, Phenethyl, Ene, Aminobenzene, Toluene, Benzene, Ammonia, Carbo carbonis monoxide, Ethyl Acetate, Acidum aceticum	Butane, Ethanol, Propylene, Butanol, Acidum aceticum, Butyl Ester, Amyl aceticum aceticum anhydride	Pentane, Hexane, Heptane, Decanus, Octane, Gasoline, Hydrogenium Sulfide, Cyclohexane, Gasoline, Kerosene, Diesel, Petroleum	Ether, Acetaldehyde, Trimethylamine		Ethyl Nitrite
IIB	Propylene, Acetylene, Cyclopropane, Coke Oven Gas	Epoxy Z-Alkane, Epoxy Propane, Butadiene, Ethylene	Dimethyl Ether, Isoprene, Hydrogenium Sulfide	Diethylether, Dibutyl Ether
IIC	Aqua Gas, Hydrogenium	Acetylene			Carbon Disulfide	Ethyl Nitrate

T4: The 'T .’ sit temperatus, geno in sex gradus. T4 significat instrumenta superficies maximae temperaturae 135°C . non excedere.