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Possible answers to U.S. industry concerns regarding IECEx Scheme

IECEx LogoThe basic reasons for the U.S. delay in participation in the Scheme focus on a few key issues:

  • U.S. acceptance of non-U.S. certification marks.
  • Elimination of U.S. national differences.
  • Third-party certification involving risk of fire and electric shock requirements - in addition to risk of explosion requirements.
  • Continuation of the U.S. Division system.

U.S. acceptance of non-U.S. certification marks

Unlike foreign legislative activities that prescribe the standards and acceptance of certificates, such as in Europe, the U.S. federal government has no regulatory control over the thousands of local AHJ's (Authority Having Jurisdiction). Therefore, there has been a perceived fear that gaining acceptance of the Scheme by the thousands of fire marshals, and electrical and building inspectors would be insurmountable. Some in the U.S. felt that this would prevent the U.S. from exhibiting a good faith effort to eliminate all differences. This is the major hurdle to full U.S. participation. However, the U.S. is not the only country dealing with issues such as these. Canada also must deal with this challenge, albeit with a significantly fewer number of AHJ's, and Europe must change legislatively as well.

Elimination of U.S. national differences

The U.S. has already made a major step toward harmonizing with the IEC in the HazLoc arena. With Zones introduced in the 1996 NEC and the subsequent publication of U.S. ANSI Zone product and installation standards (such as ANSI/UL 2279, along with other ANSI Zone documents by IEEE, ISA, and NFPA), the first step towards meeting this ultimate goal has been accomplished.

Full harmonization is allowed to occur over a transitional period. For the U.S., it would be in-line with other countries to propose a transition period of at least 10 years - as is the currently submitted period for most other member countries. This would allow a realistic time frame to eliminate the national differences in both the installation and product standards.

Third-party certification involving risk of fire and electric shock requirements - in addition to risk of explosion requirements

Some individuals believe that this major difference may prevent U.S. participation in the IECEx Scheme at any date. The concern being that, even with a transition period, the U.S. would never be able to eliminate this difference and comply with the Scheme goals of one standard, one certificate, and one mark. However, one must understand that the Scheme only addresses the equipment requirements associated with the hazard of explosive environments. These requirements are detailed in the IEC 60079 Series of publications and are the Standards covered by the Scheme.

It's important to note that there may very well be additional National regulatory requirements necessary for a product to gain entrance into a country's marketplace. In the U.S., it could be due to Federal Communications Commission (FCC) requirements or, in most cases, the need to show third-party certification involving risk of fire and electric shock requirements. As another example, in Europe, there are many additional Directives (ATEX, EMC, LVD, Machinery, Med. & Dental) that must also be met in order for a product to gain entrance and acceptance into their marketplace. The IECEx Scheme is not intended to replace all of these other regulatory requirements. It is only a method by which harmonization of risk of explosion requirements can be accomplished.

Continuation of the U.S. Division system

This is the one issue that seems to cause the greatest confusion. Some industry members believe that, for the U.S. to participate in the IECEx Scheme, the U.S. would have to eliminate the Division classification system. Or, at least relegate it to a secondary maintenance-only mode. This is not the case. The two methods of classifying hazardous locations and their associated installation and product requirements can and will coexist well into the future. The marketplace may eventually eliminate one of these methods, but it will not be a result of the Scheme rules as they exist today.

The Scheme guidelines do not include a requirement for the elimination of other national certification/installation systems, nor does the Scheme include any of the IEC 60079 installation and maintenance Standards under its rules and procedures. This is clear in reading these guidelines, and has been stated clearly in formal Scheme discussions.

Return to UL's homepage on the IECEx Scheme. Or access the IECEx Scheme Web site.

If you have any further questions or desire more detailed information on issues relating to the IECEx Scheme, please contact hazloc@ul.com.

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