John There are similarities, but they are not equivalents. I'll try to explain as concisely as I can. Class I is for gases, vapours or liquids, and consequently equates to a G atmosphere under ATEX/IECEx Class II is for dusts and equates to a D atmosphere under ATEX/IECEx Class III is for fibers and flyings and has no ATEX/IECEx equivalent, but would be treated as Dusts. Division 1 covers both the situation where ignitable concentrations of flammable gases, vapours or liquids can exist all or some of the time under normal operating conditions and consequently encompasses both Zone 0 and Zone 1. Division 2 covers the situation where ignitable concentrations of flammable gases, vapours or liquids are not likely to exist under normal operating conditions, and consequently covers Zone 2. Gas group D equates to Group IIC (propane) Gas group C equates to Group IIB (ethylene) Gas group B (hydrogen) is included in Group IIC (acetylene & hydrogen) Gas group A (acetylene) is also included in Group IIC (acetylene & hydrogen) Protection concepts are limited for Division 1 to Explosionproof, Intrinsic Safety, or Purged/Pressurized covered by UL1203, UL913 or NFPA496 respectively. Protection concepts for Division 2 include Hermetically Sealed, Non-incendive, Non-sparking (all covered by UL1604), any Division 1 method, and any IECEx method Both ATEX and IECEx standards are now aligned, based on IEC 60079 Series. These standards have also now been adopted by UL and CSA for USA and Canada, but are not yet as widely accepted as the existing standards. However, if you look at UL913 Seventh edition, for example, you will find that it is much more closely aligned with IEC 60079-11, and it is probably just a question of time before we have truly global standards for hazardous locations technology. Similarly, UL1203 is similar to IEC 60079-1. The IEC 60079-x standards must be read in conjunction with IEC 60079-0, which covers general requirements. I hope this helps.
Neil Barker Manager Central Quality e2v 106 Waterhouse Lane, Chelmsford, Essex, CM1 2QU, England Tel: +44 (0)1245 453616 Mobile: +44 (0)7801 723735 Fax: +44 (0)1245 453571 www.e2v.com <http://www.e2v.com/> P Consider the environment: do you really need to print this e mail? -----Original Message----- From: John Cochran [mailto:[email protected]] Sent: 28 July 2008 22:17 To: [email protected] Subject: Are ATEX, IEC and UL Zone classifications equivalent? My company has a UL Listing for hazardous classified Industrial Control Panels. In the file, UL equates the Class/Division/Group listings to Class/Zone/Group equivalents. Are these different from ATEX Zone listings or IEC Zone listings? What different standards are used for ATEX or IEC listings? John Cochran Compliance Engineer Strongarm Designs ______________________________________________________________________ This email has been scanned by the MessageLabs Email Security System. For more information please visit http://www.messagelabs.com/email ______________________________________________________________________ Sent by E2V TECHNOLOGIES PLC or a member of the E2V group of companies. A company registered in England and Wales. Company number; 04439718. Registered address; 106 Waterhouse Lane, Chelmsford, Essex, CM1 2QU, UK. - ---------------------------------------------------------------- This message is from the IEEE Product Safety Engineering Society emc-pstc discussion list. Website: http://www.ieee-pses.org/ To post a message to the list, send your e-mail to [email protected] Instructions: http://listserv.ieee.org/request/user-guide.html List rules: http://www.ieee-pses.org/listrules.html For help, send mail to the list administrators: Scott Douglas [email protected] Mike Cantwell [email protected] For policy questions, send mail to: Jim Bacher: [email protected] David Heald: [email protected] All emc-pstc postings are archived and searchable on the web at: http://www.ieeecommunities.org/emc-pstc
