Increased Safety “e”

Increased safety “e” is one of the types of explosion protection for electrical equipment. With this type of protection, constructional measures prevent the occurrence of electrical arcs, sparks and excessive temperatures capable of igniting an explosive gas atmosphere.
Unlike flameproof enclosure Ex d, increased safety is based on preventing an explosion from occurring inside the enclosure. The enclosure is therefore not intended to contain an explosion; instead, the equipment must be designed so that no effective ignition source can arise during the intended conditions of operation.

Essential requirements include adequate clearances and creepage distances, reliable electrical insulation, terminals protected against self-loosening, a suitable degree of enclosure protection and limitation of the maximum surface temperature. For motors and heaters, suitable protection against overload or excessive heating is also important.

An advantage of increased safety is that the equipment is generally lighter and less expensive than comparable Ex d equipment. However, this type of protection is suitable only for equipment and components in which ignition sources can be reliably prevented by design and additional protective measures. Typical applications include terminal and junction boxes, terminals, induction motors, luminaires and electrical heaters.

Equipment with the type of protection increased safety must comply with the general requirements of IEC 60079-0 and the specific requirements of IEC 60079-7. The protection is subdivided into Ex eb, providing EPL Gb or Mb and suitable for use in Zone 1, and Ex ec, providing EPL Gc and intended for use in Zone 2.

At SIQ, we also test and certify equipment with the type of protection increased safety. Certification is carried out in accordance with Directive 2014/34/EU (ATEX) and the international IECEx certification scheme.

More information:
Matej Debenc
E-mail: matej.debenc@siq.si
Tel.: +386 1 4778 227