Protective Measures Against Fires and Explosions

Primary measures are to be preferred to secondary measures, which in turn are to be preferred to tertiary ones. 

Fundamental for the protection measures is the classification of plants according to zones, which is done on the basis of a hazard analysis (cf. [42]), for which the qualitative methods of safety analysis of Chap. 9 are used. 

The areas with a hazard of explosion are divided into zones according to frequency and duration of the occurrence of an explosible atmosphere [5, 37]. They determine the extent of the measures to be taken and are defined as follows  

Zone 0 is an area in which a hazardous explosive mixture of air with flammable gases, vapours or mist is present permanently, frequently or for long periods. Zone 1 is an area in which during normal operation a hazardous explosive mixture of air with flammable gases, vapours or mist is formed occasionally. 

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