The standard “Explosive atmospheres IEC60079- Part 17: Electrical installations inspection and maintenance” calls for periodic inspection. Breaches to above, or failing meeting installation requirements, will result in loss of Ex protection! Another challenge is the risks for corrosion in flame path during operation, or risk that paint or other substances is blocking the flame paths. The challenge is that it’s impossible to inspect that an installation is done correctly without opening enclosure again. When installing Exd equipment the Ex protection is highly dependent of correct assembly of equipment ensuring no scratches on flamepath and also installation of correct gland related to explosion group and volume of enclosure. More information on different types of protection is described in following link This protection is more sophisticated and explosion integrity is taken care of by manufacturer.īoth methods of protection, Exd and Exe, is meeting standard Equipment category 2 and Equipment protection level Gb, meaning they can both be used in Zone1 installations. strength of housing and the installation and maintenance of functional flamepaths to avoid flame propagation.Įxe – Increased Safety - The protection concept is to avoid all arcs, sparks or hot surfaces. Following the protection is pure mechanical, i.e. Ignition source control can be achieved by different Methods of Explosion Protection.Įxd - Flameproof Enclosure – The protection concept is to contain the explosion and prevent the flame propagation. Suitability for installation in actual area is decided by aligning certification with requirements set in “Hazardous Area Classification”. Equipment category, Explosion Group and Temperature class. The certificate and marking of equipment is identifying a.o. Electrical equipment for installation in hazardous areas is developed, tested and certified according to internationally harmonized norms. To avoid explosion in hazardous atmosphere one have to the Control Ignition Sources. IEC 60079 – 10).įor a plant where gases, vapors and mists is posing the explosion hazard above work is dividing the plant into Zone - 0, 1 or 2, additionally also the Explosion Group and Ingnition Temperature of Hazardous Material is clearly defined. To ensure safe operation of installations in oil industry where flammable gases or vapours might be present, one have first to perform an “Hazardous Area Classification” where the risk for explosion hazards are assessed and the substances that is posing the hazard is defined.
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