Reference Source

65 records

What is the IEC or ATEX equivalent of this North American hazardous-area rating?

65 records covering 56 north american designations, one fact each. Every value is transcribed from the source that states it and carries the sentence it was taken from: 4 sources across 4 sites, last checked 2026-08-06, due for re-check by 2028-08-05. Every record is listed below, each linking the page its value came from.

Records65
Sources4
Verified
Review by
LicenceFacts extracted from freely published manufacturer and industry reference pages. Designation crosswalks are safety facts, not copyrightable expression. NFPA 70 and the IEC 60079 series are not reproduced and were not opened -- the fact is taken, never the document. Four separate publishers, no bulk take from any one.

4 records where two or more sources state different values. Both sides are reproduced on the record page, each with its own source and quote.

About this data

Crosswalk between the two concurrent hazardous-area classification systems: the North American Class / Division system of NEC Articles 500 and 505 (NFPA 70) and the CSA code, against the Zone system of IEC 60079, ATEX and IECEx. Each record is one designation in one system with its stated counterpart in the other, covering area classification (Division 1 and 2 against Zone 0, 1, 2, 20, 21, 22), gas groups (A, B, C, D against IIA, IIB, IIC, IIB+H2), dust groups (E, F, G against IIIA, IIIB, IIIC), protection concepts (explosion-proof against Ex d, intrinsically safe against Ex i, purged/pressurized against Ex p, dust-ignition-proof against Ex t, non-incendive against Ex nA/Ex ec) with the IEC standard number for each, and temperature codes T1 to T6 with their maximum surface temperatures. Answers 'is ATEX Ex d IIB T4 the same as Class I Div 1 Group C', 'what does T2D mean and is there an IEC equivalent', 'Division 1 or Zone 1 which is stricter', 'NEC Group B IEC equivalent', and 'can I install Zone 1 equipment in a Division 1 area'. Three things the mapping gets wrong when stated as a simple table: NEC 500 has no Zone 0 equivalent so Division 1 spans Zone 0 and Zone 1 and is under-specified for Zone 0; the North American temperature codes T2A, T2B, T2C, T2D, T3A, T3B, T3C and T4A have no IEC counterpart at all; and publishers disagree on NEC Group B, giving it as IIC or as IIB+H2, which changes the required flameproof gap. Every counterpart is quoted from the page that stated it and attributed, so the disagreement is visible.

The data

North American designationCategoryIEC / ATEX designationBasis or noteIEC standardMaximum surface temperature (C)
2 levels (Div 1, Div 2)system attribute3 levels (Zone 0, 1, 2)Risk gradation
Class IIIarea classificationIgnitable fibers
NEC 500 (Class/Division)system attributeATEX / IECEx (Zone)Geographic use: USA, Canada vs EU, UK, most of the world
Class II, Group Gdust groupGrain, flour, plastic dusts
NFPA 70 (adopted by AHJs)system attributeEU Directive 2014/34/EU / IECEx schemeLegal framework
Explosion-proof (XP)protection conceptEx d (Flameproof)Contain the explosion inside the enclosureIEC 60079-1
Flameproof enclosureprotection conceptEx dFlameproof enclosure
Increased safetyprotection conceptEx eIncreased safety
Intrinsically Safe (IS)protection conceptEx i (Ex ia, Ex ib)Limit energy below ignition thresholdIEC 60079-11
Intrinsically Safeprotection conceptEx iIntrinsic safety
Encapsulationprotection conceptEx mEncapsulation
Non-incendiveprotection conceptEx nA / Ex ecNormal operation cannot cause ignitionIEC 60079-15 / -7
Hermetically sealedprotection conceptEx nC / Ex mSeal ignition source from atmosphereIEC 60079-15 / -18
Purged/Pressurizedprotection conceptEx p (Ex px, Ex py, Ex pz)Maintain positive pressure with inert gasIEC 60079-2
Pressurizationprotection conceptEx pPressurization
Dust-ignition-proofprotection conceptEx t (Dust protection by enclosure)Prevent dust ingress and limit surface temperatureIEC 60079-31
Group Egas groupMetal dust
Group Fgas groupCarbon dust
Group Ggas groupGrain / flour dust
Groups A, B, C, Dsystem attributeGroups IIC, IIB, IIAGas classification
Explosion-proof (XP), intrinsically safe (IS)system attributeIEC-aligned types (Ex d, Ex i, Ex e, etc.)Protection concept
Class I, Group Dgas groupIIAPropane
Group Dsources differgas groupIIAMESG >0.90 mm
Class I, Group Cgas groupIIBEthylene
Group Csources differgas groupIIBMESG 0.50–0.90 mm
Class I, Group Bgas groupIIB + H2Hydrogen
Class I, Group Agas groupIICAcetylene
Group Asources differgas groupIICMESG <0.50 mm
Group Bgas groupIICHydrogen
Group Bgas groupIIC (partially IIB+H₂)MESG <0.50 mm
Class IIIdust groupIIIAFibers and flyings
Class II, Group Fdust groupIIIBCarbon dusts
Class II, Group Edust groupIIICMetal dusts
NRTLs (UL, FM, CSA)system attributeNotified Bodies (ATEX) / ExCBs (IECEx)Certification body
T1temperature codeT1Ignition temperature of gas / dust >450450
T2temperature codeT2Ignition temperature of gas / dust >300-450300
T3temperature codeT3Ignition temperature of gas / dust >200-300200
T4temperature codeT4Ignition temperature of gas / dust >135-200135
T5temperature codeT5Ignition temperature of gas / dust >100-135100
T6temperature codeT6Ignition temperature of gas / dust >85-10085
T2Atemperature codeIgnition temperature of gas / dust >280-300280
T2Btemperature codeIgnition temperature of gas / dust >260-280260
T2Ctemperature codeIgnition temperature of gas / dust >230-260230
T2Dtemperature codeIgnition temperature of gas / dust >215-230215
T3Atemperature codeIgnition temperature of gas / dust >180-200180
T3Btemperature codeIgnition temperature of gas / dust >165-180165
T3Ctemperature codeIgnition temperature of gas / dust >160-165160
T4Atemperature codeIgnition temperature of gas / dust >120-135120
Class Iarea classificationZone 0, 1, 2 (gas)Flammable gases and vapors
Class I (gas), II (dust), III (fibers)system attributeZone 0, 1, 2 (gas); Zone 20, 21, 22 (dust)Hazard basis
Class I Division 1area classificationZone 0Continuous hazard
(no NEC 500 equivalent)area classificationZone 0Explosive atmosphere continuously or for long periods (>1000 hrs/yr)
(no NEC equivalent)area classificationZone 0Explosive atmosphere present continuously or for long periods
Division 1area classificationZone 0 / Zone 1Hazard present during normal operation
Class I Division 1area classificationZone 1Frequent hazard
(no NEC equivalent)area classificationZone 1Explosive atmosphere likely during normal operation
Division 1area classificationZone 1 (+ Zone 0)Explosive atmosphere likely during normal operation (10–1000 hrs/yr)
Class I Division 2area classificationZone 2Occasional hazard
Division 2sources differarea classificationZone 2Explosive atmosphere not likely; only abnormal conditions (<10 hrs/yr)
(no NEC equivalent)area classificationZone 2Explosive atmosphere unlikely in normal operation, only short duration eg. accidental leakage
Class IIarea classificationZone 20, 21, 22 (dust)Combustible dust
Class II Groups E, F, Gsystem attributeZone 20, 21, 22 (IIIA, IIIB, IIIC)Dust classification
(no NEC equivalent)area classificationZone 20Combustible dust present continuously
(no NEC equivalent)area classificationZone 21Dust likely during normal operation
(no NEC equivalent)area classificationZone 22Dust unlikely except briefly

Where this came from

Every record above links the page it was taken from and quotes the sentence that states it. These are the 4 sources this dataset was assembled from.

Machine-readable

From your own code

Same records, same quotes, without scraping the page: refsource is on PyPI and npm. Each value comes back carrying the URL it was read from and the sentence on that page that states it — .source and .quote sit on the value itself rather than in a side channel, so the checking step is available instead of skipped.

pip install refsource
refsource lookup ex-classification-system-crosswalk category="system attribute"

npx -y refsource lookup ex-classification-system-crosswalk category="system attribute"

Set your AI assistant up to use this

Two files and no account. Put this in .mcp.json at the root of your project — Claude Code, Cursor, Windsurf, VS Code and Codex all read that file — and your assistant can look this dataset up instead of recalling it. The server is remote, keyless and read-only.

{
  "mcpServers": {
    "referencesource": {
      "type": "http",
      "url": "https://referencesource.org/mcp"
    }
  }
}

Add to Cursor · or, on the command line: claude mcp add --transport http referencesource https://referencesource.org/mcp --scope project

Then one line in the project's CLAUDE.md or AGENTS.md, so the assistant knows when to reach for it:

When a question needs "North American vs IEC/ATEX explosion protection designations", call the referencesource MCP server at https://referencesource.org/mcp (tool `search_records`, dataset_slug `ex-classification-system-crosswalk`) instead of answering from memory — every record it returns carries its source URL and a verbatim quote from that page.

What each tool does, and the servers built over single registers: Connect your AI assistant.

65 records. last verified against source . due for re-check by .

Licence. Facts extracted from freely published manufacturer and industry reference pages. Designation crosswalks are safety facts, not copyrightable expression. NFPA 70 and the IEC 60079 series are not reproduced and were not opened -- the fact is taken, never the document. Four separate publishers, no bulk take from any one.