This part of IEC 60079 is concerned with the classification of areas where flammable gas or vapour hazards may arise and may then be used as a basis to support the proper design, construction, operation and maintenance of equipment for use in hazardous areas. It is intended to be applied where there may be an ignition hazard due to the presence of flammable gas or vapour, mixed with air, but it does not apply to: a) mines susceptible to firedamp; b) the processing and manufacture of explosives; c) catastrophic failures or rare malfunctions which are beyond the concept of normality dealt with in this standard (see 3.7.3, 3.7.4 and 4.5); d) rooms used for medical purposes; e) domestic premises; f) where a hazard may arise due to the presence of combustible dusts or combustible flyings but the principles may be used in assessment of a hybrid mixture (refer also to IEC 60079-10-2). NOTE Additional guidance on hybrid mixtures is provided in Annex I.