Area where an explosive atmosphere is present or can be expected in quantities that exact special measures with regard to the design, the installation and the use of equipment.
Remark: layers, deposits and the accumulation of combustible dustDust, fibres or suspended matter that can burn or smoulder in the air and generate explosive mixtures with the air in the presence of atmospheric pressure and at normal temperatures. should be regarded as a source prone to the formation of an explosive atmosphere.