IEC International Electrotechnical

As time passes, national standards for area classification have been superseded by international standards (IEC, International Electrotechnical Commission, Geneva/Switzerland, and EN, European Standard or European Norm, established by CENELEC, Comite Europeen de Normalisation Electrotechnique, Brussels/Belgium), which have been adopted as subsequent national standards. In the member countries of the European Community (EC), a joint area classification is defined by a directive (Directive 1999/92/EC of the European Parliament and of the Council, dated 1999-12-16). 

In the course of the integration of European states and the removal of trade barriers, national standardization loses importance considerably. The majority of electrical standards comes into existence by international cooperation with IEC, International Electrotechnical Commission, Geneva/Switzerland. On the basis of IEC Standards many European Standards have been developed in the past. This work has been done by CENELEC, Comite Europeen de Normalisation Electrotechnique, Brussels/Belgium. European Standards or Norms (EN) often deviate from their IEC origins in their technical content. To avoid double action and to ensure a more effective standardization procedure, IEC and CENELEC are now working in closer cooperation. CENELEC is a private organization and does not act as an institution of the European Union at all. This fact indicates that European Standards need a legal act to come into force. Members of CENELEC are the national committees for standardization of the member states (not identical with the European Union). 

Table 3.12 The IEC (International Electrotechnical Commission) members and associates (as at 1999-12-31)...

ISO/IEC (International Electrotechnical Commission) 17011, Conformity assessment— General requirements for accreditation bodies accrediting conformity assessment bodies... and... 

CEI/IEC Commission Electrotechnique Internationale/ International Electrotechnical Commission... 

It is the general consensus within the worldwide fire community that the only proper way to evaluate the fire safety of products is to conduct full-scale tests or complete fire-risk assessments. Most of these tests were extracted from procedures developed by the American Society for Testing and Materials (ASTM) and the International Electrotechnical Commission (IEC). Because they are time tested, they are generally accepted methods to evaluate a given property. Where there were no universally accepted methods the UL developed its own. 

Conformity Assessment - Vocabulary and General Principles , ISO/IEC 17000 2004 International Organization for Standardization (ISO)/International Electrotechnical Commission (IEC), Geneva, Switzerland, 2004. 

IEC (1998), IEC 61508, Functional Safety of Electrical/Electronic/Programmable Electronic Safety-related Systems, Parts 1-7, Geneva International Electrotechnical Commission. 

IEC (2001), IEC 61511, Functional Safety Instrumented Systems for the Process Industry Sector, Parts 1-3. (Draft in Process), Geneva International Electrotechnical Commission. 

However, the standard used in the United States and the standards used in Europe do not coincide. The dissimilarities are due to a difference in the manner in which hazardous environments are classified and to a divergence in philosophy over the safety factor employed. NFPA 493 uses a safety of 1.5 pertaining to the total energy, while the International Electrotechnical Commission (IEC) and European Committee for Electrotechnical Standardization (CENELEC) require a safety factor of 1.5 for the voltage or current, which relates to a 2.25 factor of safety for the energy. 

References Guidelines for Safe and Reliable Instrumented Protective Systems, American Institute of Chemical Engineers, New York, 2007 ISA TR84.00.04, Guidelines for the Implementation of ANSI/ISA 84.00.01-2004 (IEC 61511), Instrumentation, Systems, and Automation Society, N.C., 2005 ANSI/ISA 84.00.01-2004, Functional Safety Safety Instrumented Systems for the Process Industry Sector, Instrumentation, Systems, and Automation Society, N.C., 2004 IEC 61511, Functional Safety Safety Instrumented Systems for the Process Industry Sector, International Electrotechnical Commission, Geneva, Switzerland, 2003. 

Safe Automation and ANSI/ISA 84.01-1996 served as significant technical references for the first international standard, IEC 61511, issued by the International Electrotechnical Commission (IEC). In the United States, IEC 61511 was accepted by ISA as ISA 84.00.01-2004, replacing the 1996 standard. In 2004, the European Committee for Electrotechnical Standardization (CENELEC) and the American National Standards Institute (ANSI) recognized IEC 61511 as a consensus standard for the process industry. IEC 61511 covers the complete process safety management life cycle. With its adoption, this standard serves as the primary driving force behind the work processes followed to achieve and maintain safe operation using safety instrumented systems. 

International Electrotechnical Commission IEC 79-4. Electrical Apparatus for Explosive Gas Atmospheres. Second Edition, 1975. 

Polymeric materials - short term property evaluations hot wire ignition, Underwriters Laboratory Bulletin UL-746A, Underwriters Laboratory, Northbrook, IL, 1984, pp. 24-25 (ASTM D3874-97, American Society for Testing and Materials Glow Wire Test (IEC 695-2-1), International Electrotechnical Commission). 

International Electrotechnical Commission, lEC TC 105 Strategic Policy Statement, March, 2000, CA/1719A/R, http //www.iec.ch. 

The useful life of a practical primary battery is determined principally by the nature of its discharge pattern. Thus the best way of assessing a system for some particular application is to subject it to a discharge which simulates the service conditions. Tests have therefore been developed which recognize the principal function of various types of battery and specify the generation of intermittent or continuous currents of appropriate levels. Such procedures have been standardized for batteries of uniform size and cell configuration by bodies such as the International Electrotechnical Commission (IEC) and the American National Standards Institute (ANSI). New test routines are continually being devised to keep pace... 

In the electrical field the International Electrotechnical Commission (IEC) performs the same function as ISO. The work of this body is of interest where rubbers are used in electrical insulation, etc. As regards electrical test methods for rubber, ISO and BSI have tended to adapt the basic procedures and principles standardised by IEC or to rely on the IEC standards. 

Under this definition, the value of IHDX is always 100%. This method of quantifying the harmonics is known as harmonic distortion based on the fundamental. This is the convention used by the Institute of Electrical and Electronic Engineers (IEEE) in the U.S. The European International Electrotechnical Commission (IEC) quantifies harmonics based on the total RMS value of the waveform. Using the same example shown above, the RMS value of the waveform is ... 

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