gases, such as ammonia, chlorine or hydrogen chloride, fluorine or hydrogen fluoride, carbon oxides, sulphur compounds, nitrogen oxides, hydrogen, sulphur dioxide, carbonyl chloride.
van gassen, zoals ammoniak, chloor of chloorwaterstof, fluor of fluorwaterstof, kooloxiden, zwavelverbindingen, stikstofoxiden, waterstof, zwaveldioxide, carbonyldichloride,