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Industrial Applications 8 min readApril 19, 2026

ATEX vs IECEx Certification: Hazardous Area Cable Requirements Explained

Installing electrical cable in explosive atmospheres — oil refineries, offshore platforms, gas processing plants, solvent handling facilities — requires specific hazardous area certification. This guide explains ATEX, IECEx, FM, and the Zone/Division classification system.

What is ATEX Certification?

ATEX stands for Atmosphères Explosibles — the EU directive (2014/34/EU) governing equipment and protective systems intended for use in potentially explosive atmospheres. ATEX certification is mandatory for all electrical equipment (including cable and accessories) used in hazardous areas within European Union member states. The ATEX marking on a product indicates it has been tested and certified by a Notified Body.

What is IECEx Certification?

IECEx is the International Electrotechnical Commission's scheme for certifying equipment for use in explosive atmospheres — the international equivalent of ATEX. IECEx is accepted in over 50 countries including Australia, China, South Africa, Saudi Arabia, Middle East, and many Asian markets. While ATEX is mandatory in the EU, IECEx provides a single globally recognized certification for manufacturers selling to multiple international markets.

ATEX vs IECEx vs FM: Key Differences

SchemeGoverning BodyPrimary MarketsClassification System
ATEXEU Notified BodiesEuropean UnionZone 0/1/2 (gas), Zone 20/21/22 (dust)
IECExIEC ExCB (national bodies)Global (50+ countries)Zone 0/1/2 (same as ATEX)
FM ApprovalFM Global (USA)North AmericaClass/Division (Class I Div 1/2)
UL HazlocUnderwriters LaboratoriesNorth AmericaClass/Division (same as FM)
CSA HazlocCSA GroupCanadaClass/Division (CEC)

Hazardous Area Zone Classification

Zone 0

Explosive atmosphere present continuously or for long periods

Example: Interior of fuel storage tank

Zone 1

Explosive atmosphere likely to occur in normal operation

Example: Pump room, near process equipment vents

Zone 2

Explosive atmosphere unlikely in normal operation, but possible

Example: Surrounding Zone 1 areas, flammable storage rooms

Class I Div 1

US/Canada equivalent of Zone 0/Zone 1 combined

Example: Same as Zone 0 and Zone 1

Class I Div 2

US/Canada equivalent of Zone 2

Example: Same as Zone 2

Cable Requirements for Hazardous Areas

Hazardous area cable installations must comply with IEC 60079-14 (international) or NEC Article 500-516 (North America). Key cable requirements include:

  • Mechanical protection: Armored cable (SWA), or cable in steel conduit, required in Zone 1 / Class I Div 1
  • Sheath temperature rating: Cable outer sheath must have a temperature class (T1–T6) appropriate for the gas group's ignition temperature
  • Gland selection: Cable glands must be ATEX/IECEx certified and appropriate for the cable type and zone
  • Heating cable: Must be FM Approved (North America) or ATEX/IECEx certified — self-regulating type preferred for most freeze protection applications
  • Documentation: Installation must include Ex documentation, area classification drawings, and equipment schedules for inspection

FAQs

Can I use ATEX certified cable in the US?

ATEX certification is an EU directive and is not directly accepted in the US. For North American hazardous area installations (Class I Div 1/2), you need FM Approval or UL Hazloc listing.

Is IECEx accepted in Europe (ATEX countries)?

IECEx is accepted in many countries but ATEX certification is specifically required for EU member states under the ATEX Directive (2014/34/EU). Some EU countries accept IECEx alongside ATEX; verify with your local authority.

What type of cable is required in Zone 1?

Zone 1 typically requires armored cable or cable in conduit, with a sheath rated for the hazardous environment. The cable system (including glands and enclosures) must achieve ATEX/IECEx Exd, Exe, or Exi category as appropriate.

ATEX/IECEx and FM Certified Cable

Shanghai Unicorn Cable supplies ATEX/IECEx rated and FM-approved cable and heating cable for hazardous location installations. Request a quote with your zone classification and application details.

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