ATEX is the name commonly given to the two European Directives for controlling explosive atmospheres:
1) Directive 99/92/EC (also known as ‘ATEX 137’ or the ‘ATEX Workplace Directive’) on minimum requirements for improving the health and safety protection of workers potentially at risk from explosive atmospheres. The text of the Directive and the supporting EU produced guidelines are available on the EU website.
2) Directive 94/9/EC (also known as ‘ATEX 95’ or ‘the ATEX Equipment Directive’) on the approximation of the laws of Members States concerning equipment and protective systems intended for use in potentially explosive atmospheres. The text of the Directive and EU produced supporting guidelines are available on the EU website.
A mixture of hazardous gases and air may be ignited by coming into contact with a hot surface. The conditions under which a hot surface will ignite a gas depends on surface area, temperature, and the concentration of the gas. The maximum possible surface temperature of equipment is shown in the ATEX Explosion Classification as a “T” Value, which ranges from T1 to T6 in order of decreasing value (so T6 is “Safer”).
Protection Techniques refer to the methods used to protect electrical and non-electrical sources from igniting an explosive atmosphere. These methods are defined in national, regional, and international codes and standards.
Flameproof is a type ‘d’ (Ex d) of protection where the enclosure will withstand an internal explosion of a flammable mixture that has penetrated into the interior, without suffering damage and without causing ignition, through any joints or structural openings in the enclosure, of an external gas atmosphere consisting of one or more of the gases or vapors for which it is designed.
Increased Safety ‘e’
Increased Safety is a type ‘e’ (Ex e) protection that is applied to electrical equipment, which it does not produce arcs or sparks in normal service or under specified abnormal conditions. Additional measures are applied, so it gives increased security against the possibility of excessive temperatures and of the occurrence of arcs and sparks.
Ignitable concentrations of flammable gases or vapors which are likely to occur under normal operating conditions.
There are two general sources of ignition, from an electrical source and from a non-electrical source. Examples of specific electrical sources
include arcing between contacts of a switch or breakdown between traces on a printed wiring board. Examples of non-electrical sources include the hot surfaces of a brake or electrostatic charging of a non-metallic fluid handling system.
Hazardous areas are classified into zones based on an assessment of the frequency of occurrence and duration of a potentially explosive gas atmosphere. IEC60079-10-1 defines the areas in an explosive atmosphere such as:
« Explosive atmosphere: mixture with air, under atmospheric conditions, flammable substances in the form of gas, vapor, dust, fibers, or flyings, which after ignition it permits self-sustaining propagation.
An area in which an explosive gas atmosphere is continuously present, for long periods of time or frequently.
An area in which an explosive gas atmosphere is likely to occasionally occur in normal operation.
An area in which an explosive gas atmosphere is not likely to occur in normal operation, but if it does occur, will only persist for a short period of time.
Compliance certifications have always been a critical part of our product development strategy. And, we were an early adopter of explosion-proof certifications for our purpose-built hazardous location air movers.
Today, our commitment to delivering full-unit certified and explosion-proof ventilation solutions remains unmatched. We continue to build on this foundation by adding new innovative products as well as international certifications to better serve our customers in different regions of the world.
Our ventilators currently hold full-unit hazardous location certifications for ATEX, IECEx, INMETRO and CE.
While various standards exist that are in line with IEC 60079 Standard on Explosive Atmospheres, countries use these principles in their regulations in different ways. Some countries are making these standards mandatory through their legislative act. Others are making compliance with the standards a means of proving compliance with the essential health and safety requirements laid out in the legislation. And, a third group relies heavily on the self-correcting nature of the chain of liability where few mandatory elements of the standard exist.
This provides a challenging global operating environment for a manufacturer, but these barriers are critical to surmount to maximize the safety of the users and facilities how our equipment operates.