These girl names were at the top of their popularity during 1970-1979 (usage of 0.322%) and have become much less widespread since (usage 0.14%, down 56.5%), with the form Jolene becoming less fashionable. Shown below is an analysis of the popularity of the girl name Jolena and affiliated names.hese girl names were at the top of their popularity during 1970-1979 (usage of 0.322%) and have become much less widespread since (usage 0.14%, down 56.5%), with the form Jolene becoming less fashionable. Shown below is an analysis of the popularity of the girl name Jolena and affiliated names.
Groups further define the hazard in Class I and Class II areas. In Class I, there are Group A (Acetylene and similar gases), Group B (Hydrogen and similar gases), Group C (Ethylene and similar gases) and Group D (Propane and similar gases). Hazardous dusts and fibers (Class II & III respectively) are not treated in Article 505.
Acetylene may also be generated by raising the temperature of various hydrocarbons to the point where their atomic bonds break, or crack, in what is known as a thermal cracking process. 1  The gas passes through a water scrubber, which removes much of the carbon soot.cetylene is a hydrocarbon consisting of two carbon atoms and two hydrogen atoms. Its chemical symbol is C 2 H 2. For commercial purposes, acetylene can be made from several different raw materials depending on the process used.