IEC 60079-18:2025
Explosive atmospheres - Part 18: Equipment protection by encapsulation "m"
IEC 60079-18:2025 gives the specific requirements for the construction, testing and marking of electrical Ex Equipment, parts of electrical Ex Equipment and Ex Components with the Type of Protection encapsulation "m" (hereinafter referred to as "m" Equipment) intended for use in explosive gas atmospheres or explosive dust atmospheres. For Levels of Protection "mb" and "mc", this document applies where the rated voltage does not exceed 11 kV ACRMS or DC. For Level of Protection "ma", this document applies where the rated voltage does not exceed 1 kV ACRMS or DC. This document does not take account of any hazard due to an emission of flammable or toxic gas from the dust. This document supplements and modifies the general requirements of IEC 60079-0. Where a requirement of this document conflicts with a requirement of IEC 60079-0, the requirement of this document takes precedence. This fifth edition cancels and replaces the fourth edition published in 2014 and Amendment 1:2017. This edition constitutes a technical revision. This International Standard is to be used in conjunction with IEC 60079-0, Explosive atmospheres - Part 0: Equipment - General requirements. Users of this document are advised that interpretation sheets clarifying the interpretation of this document can be published. Interpretation sheets are available from the IEC webstore and can be found in the "history" tab of the page for each document. Please see the foreword to this document for the list of significant technical changes with respect to the previous edition.
IEC 60079-18:2025 gives the specific requirements for the construction, testing and marking of electrical Ex Equipment, parts of electrical Ex Equipment and Ex Components with the Type of Protection encapsulation "m" (hereinafter referred to as "m" Equipment) intended for use in explosive gas atmospheres or explosive dust atmospheres. For Levels of Protection "mb" and "mc", this document applies where the rated voltage does not exceed 11 kV ACRMS or DC. For Level of Protection "ma", this document applies where the rated voltage does not exceed 1 kV ACRMS or DC. This document does not take account of any hazard due to an emission of flammable or toxic gas from the dust. This document supplements and modifies the general requirements of IEC 60079-0. Where a requirement of this document conflicts with a requirement of IEC 60079-0, the requirement of this document takes precedence. This fifth edition cancels and replaces the fourth edition published in 2014 and Amendment 1:2017. This edition constitutes a technical revision. This International Standard is to be used in conjunction with IEC 60079-0, Explosive atmospheres - Part 0: Equipment - General requirements. Users of this document are advised that interpretation sheets clarifying the interpretation of this document can be published. Interpretation sheets are available from the IEC webstore and can be found in the "history" tab of the page for each document. Please see the foreword to this document for the list of significant technical changes with respect to the previous edition.
IEC 60079-18:2014 gives the specific requirements for the construction, testing and marking of electrical equipment, parts of electrical equipment and Ex components with the type of protection encapsulation "m" intended for use in explosive gas atmospheres or explosive dust atmospheres. This part applies only for encapsulated electrical equipment, encapsulated parts of electrical equipment and encapsulat ed Ex components (hereinafter always referred to as "m" equipment) where the rated voltage does not exceed 11 kV. The application of electrical equipment in atmospheres, which may contain explosive gas as well as combustible dust simultaneously, may require additional protective measures. This standard does not apply to dusts of explosives, which do not require atmospheric oxygen for combustion, or to pyrophoric substances. This standard does not take account of any risk due to an emission of flammable or toxic gas from the dust. This standard supplements and modifies the general requirements of IEC 60079-0. Where a requirement of this standard conflicts with a requirement of IEC 60079-0, the requirement of this standard takes precedence. This fourth edition cancels and replaces the third edition of IEC 60079-18:2009, and constitutes a technical revision. Please refer to the foreword of the document for a listing of the technical changes with respect to the previous edition. Keywords: encapsulation "m", explosive gas atmospheres, explosive dust atmospheres This publication is to be read in conjunction with IEC 60079-0:2011. The contents of the corrigendum of July 2018 have been included in this copy.
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