Types of protection

Further information as PDF

• IEC 60079-0 for gases and vapours
• IEC 61241-0 for dusts and
• EN 13463-1 for non-electrical devices.

Uniform protection requirements concerning several types of protection such as protection against electrostatic charging, provision of a potential bond for metal enclosures, or mechanical strength against impact, are summarized in these standards under general engineering requirements. In this case, individual, more specific standards can demand either more stringent requirements or less stringent ones.

These requirements are based partially on those for electrical equipment for gases and vapours, deviations for dust and non-electric equipment are contained in the individual basic standards. Categories 1 to 3 with which the equipment has to comply can also include different general requirements.

The general temperature range for the application of explosion-proof equipment is defined as -20 °C to +40 °C. Permissible deviations extending or restricting the temperature range must be specified.

The parameters determined at approximately +20 °C in the laboratory for the subgroups IIA, IIB and IIC apply for a temperature range of ± 40 K - that is to say also from -20 °C to +60 °C.

These two temperature ranges take, on the one hand, the situation at the work place into account and also, on the other, a certain heating up of the equipment during operation. The explosion pressure, permissible gap widths and permissible non-igniting currents change outside this temperature range. These aspects have to be considered when applying the equipment, and may require different test conditions.