IECEx: a view from the chair (5)
12 March 2015
Prof. Dr. Thorsten Arnhold, the chairman of IECEx, gives his insight on developments within IECEx and the wider world of explosion protection. This month, a look at some of the most important differences between ATEX and IECEx.
At many meetings with customers and regulating authorities during my first year as the chairman of IECEx, I was asked to explain the most important differences between ATEX and IECEx. Especially outside of the European Union, it is important to highlight the benefits of the IECEx System compared with the ATEX directive.
To name only the three most important aspects, I want to mention the full life cycle approach of IECEx, the 24/7 availability of all valid IECEx certificates via the online database and the possibility of all member countries to participate actively in the development of this global conformity assessment system.
The list of advantages of the IECEx System is much longer, but one aspect of the ATEX directive was a real benefit for manufacturers and end customers in the past: since it is a directive and not a conformity assessment scheme, ATEX permits a certain flexibility to fulfil its requirements.
The “Essential health and safety requirements” are defined in appendix II.
To get an ATEX certificate, the manufacturer must meet these requirements with its respective product. To use harmonised European standards (which are almost identical with the IEC standards) is one and in many cases the most convenient solution.
But there can be cases in which the standards do not yet cover a technical solution and here the manufacturer has the possibility to demonstrate that its product is in accordance with the “Essential health and safety requirements”.
The technical process is strongly supported by this and it is not necessary to wait for the next or later generations of standards to bring new technical solutions into the hazardous area. In the past, typical examples of such cases have been the cage clamp terminals and bi pin lamps for fluorescent light fittings.
When these solutions came up before ATEX it was very complicated and time consuming to get certificates. Under ATEX, however, it is quite easy. This can be shown by the example of LEDs, which quickly found their way to hazardous area lighting solutions.
IECEx in contrast is a conformity assessment system. To get a certificate, the manufacturer has to fulfil the requirements of a standard – full stop. So the question was: what to do with new technical solutions which can get an ATEX certificate quite quickly but are not available for the rest of the world? Waiting for the next generation of IEC standards, which can sometimes take seven years, was no option.
So it was decided to develop a new standard which defines a “frame set of requirements” similar to the appendix II of the ATEX directive. The first edition of this new standard, IEC 60079 – 33, was published in 2012. The scope is defined as following: “…This part of IEC 60079 applies to:
• Electrical equipment employing a method of protection not covered by any existing standard in the IEC 60079 series,
• Electrical equipment employing one or more recognized types of protection where the design and construction is not fully compliant with the standard for the type of protection,
• Electrical equipment where the intended use is outside the parameters of the scope of other standard for the type of protection.”
This new protection method “s” is “…not intended for equipment that is covered by the scope of other IEC equipment standards unless:
• It is clearly demonstrated that compliance with the type of protection is not feasible, and
• additional measures are applied to establish an equivalent equipment protection level.”
Since such a standard is quite different from the rest of the IEC 60079 standards, it was decided that the IECEx organisation should be strongly involved in the development and further maintenance of that document. So at the 2014 IECEx Management Committee meeting in The Hague, the Draft Operational Document for the implementation of IEC 60079-33 (Ex s) was discussed and finally endorsed. The purpose of this document is to provide a framework within the IECEx Equipment Certification Scheme for the procedures to be followed when an Ex Certification Body (ExCB) receives an application for certification to the requirements of IEC 60079 – 33.
With both documents, the new IEC standard and the new IECEx Operational Document (OD), all necessary preconditions have been developed to establish a similar flexibility and openness for new technical solutions to be transferred into hazardous areas as under the ATEX directive.
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