SI | EN
Four protection principles can prevent equipment from becoming an ignition source. The types of protection listed as examples in the overview are discussed in a different chapter.

An important precondition for all the protection principles is that parts which are in unhindered contact with the explosive atmosphere must not be able to reach non-permitted temperatures with respect to the ignition temperature of substances present in the site of installation. This means that the ignition temperature is relevant for all protection principles.

The protection principles can be equally applied to electrical and non-electrical devices and for gases and for dusts. The principles allow for a design in various safety categories in accordance with the Directive 94/9/EC or the Equipment Protection Level (EPL) according with EN 60079-0 ff:

Category 1 – with very high level of protection and thus a very high degree of safety
Category 2 – with high level of protection and therefore a high degree of safety
Category 3 – with normal level of protection and therefore a conventional degree of safety
EPL a – with very high level of protection and thus a very high degree of safety
EPL b – with high level of protection and therefore a high degree of safety
EPL c – with normal level of protection and therefore a conventional degree of safety

Explosive mixtures can enter the equipment in which an ignition source may be located, enter and be ignited. The transmission of running inside explosion on the surrounding space is excluded.

Examples of types of protection:
  • Flameproof enclosures (Ex d) electrical and non-electrical devices
  • Powder filling (Ex q) electrical devices

The operating equipment has an enclosure which prevents the penetration of the explosive mixture and/or contact with the function-related possible internal sources of ignition.

Examples of types of protection:
  • Pressurized enclosures (Ex p) - electrical and non-electrical devices
  • Protection by enclosures (Ex t) - electrical devices
  • Oil immersion (Ex o) - electrical devices
  • Liquid immersion (Ex k) - non-electrical devices
  • Encapsulation (Ex m) - electrical devices

Explosive mixtures can penetrate the enclosure of the operating equipment but must not be ignited. Sparks and temperatures capable of causing ignitions must be prevented.

Examples of types of protection:
  • Non-sparking devices (Ex e) - electrical devices
  • Protection by constructional safety (Ex c) - non-electrical devices

Explosive mixtures can penetrate the operating equipment’s enclosure but must not be ignited. The occurrence of sparks and increased temperatures must be limited.

Examples of types of protection:
  • Intrinsically safe (Ex i) - electrical devices
  • Protection by control of ignition source (Ex b) - non-electrical devices

BARTEC applies these protection principles to its different pieces of equipment according to the application for which they are going to be used.