In general these are: heating gas, hydrocarbons, glues and adhesive solvents, paint solvents and thinners, varnishes and resins, manufacturing additives for pharmaceutical products, artificial dyes, aromas and perfumes, manufacturing agents for the following materials: plastics, rubbers, man-made textiles and chemical cleaning products, products used in the treatment and manufacturing of alcohols and derivates, etc.
These gases or vapours are classified into three subdivisions: A, B and C, according to their minimum experimental safety gap (MESG) and their minimum ignition current (MIC).
Warning: it should not be forgotten that certain products used in powder and dust form can also in certain conditions become active agents of an explosion.
These are powders or dust of: magnesium, aluminium, sulphur, cellulose, corn starch, epoxy resins, polystyrenes, coal, wood, corn (flour), milk, sugar (icing sugar), etc.