A digital/PDF version is available from the Energy Institute (EI), EEMUA's joint publisher for this product.
EEMUA 246 provides guidance on managing the ignition risks of Ex electrical equipment located in hazardous areas arising from flammable vapours and gases.
Inspection of Ex electrical equipment is critical to assuring the continuing integrity of the types of protection that enable its use in potentially flammable atmospheres, hence management of the major accident hazard ignition control boundary. However, such inspections are sometimes not carried out adequately both with regard to frequency of inspection, grade of inspection and completeness of the portfolio of Ex electrical equipment installed. This is due in part to the onerous requirements of IEC 60079-17 with respect to close inspection, in three years, of the several thousand pieces of Ex electrical equipment at a typical installation handling flammable fluids in major hazard industries (both onshore and offshore) or allied process industries. In addition, inspection of Ex electrical equipment is often carried out at the same level of inspection (frequency of inspection, grade of inspection, etc.) without adjustment for the different ignition risks that might apply. Furthermore, there is a lack of clarity in IEC 60079-17 regarding carrying out sample inspections, particularly with respect to detailed inspections.
The EEMUA 246 guidance is mapped against a Safety management system (SMS) framework which should be applied throughout the lifecycle of Ex electrical equipment located in hazardous areas arising from flammable vapours and gases. These guidelines further develop the Risk-based inspection (RBI) concept by providing an RBI sampling methodology which will complement an RBI inspection process that takes into account As low as reasonably practicable (ALARP) principles. The RBI methodology is intended for application to sampling of electrical equipment as defined within IEC 60079-17. The methodology applies random sampling to lots.
These guidelines are based primarily on the UK legislative and regulatory framework and international standards; yet its guidance is globally applicable, provided it is read, interpreted and applied in conjunction with relevant national and local statutory legislation and standards. Where the requirements differ, the more rigorous should be adopted.