UNE-EN 60079-10-1:2016

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 selection and installation 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)areas where a hazard may arise due to the presence of combustible dusts or fibres (refer IEC 60079-10-2); d)catastrophic failures or rare malfunctions which are beyond the concept of abnormality dealt with in this standard (see 3.7.3 and 3.7.4);e)rooms used for medical purposes;f)commercial and industrial applications where only low pressure fuel gas is used for appliances e.g. for cooking, water heating and similar uses, where the installation is compliant with relevant gas codes;g)domestic premises.This standard does not take into account the consequences of ignition of an explosive 253 atmosphere.Flammable mists may form or be present at the same time as flammable vapours. Liquids not considered to be hazardous in terms of this standard (due to the flash point), when released under pressure may also generate flammable mists. In such cases, the strict application of area classification for gases and vapours may not be appropriate as the basis for selection of equipment. Information on flammable mists is provided in Annex G.For the purpose of this standard, an area is a three-dimensional region or space.Atmospheric conditions include variations above and below reference levels of 101,3 kPa (1013 mbar) and 20 °C (293 K), provided that the variations have a negligible effect on the explosion properties of the flammable substances.In any process plant, irrespective of size, there may be numerous sources of ignition apart from those associated with equipment. Appropriate precautions will be necessary to ensure safety in this context. This standard may be used with judgement for other ignition sources.