{
  "name": "North American vs IEC/ATEX explosion protection designations",
  "description": "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.",
  "url": "https://referencesource.org/ex-classification-system-crosswalk/",
  "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.",
  "last_verified": "2026-08-06",
  "stale_after": "2028-08-05",
  "sources": [
    "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
    "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
    "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
    "https://ldpi-inc.com/resources/classification-codes/class-1-locations/"
  ],
  "records": [
    {
      "category": "system attribute",
      "north_american_designation": "2 levels (Div 1, Div 2)",
      "iec_designation": "3 levels (Zone 0, 1, 2)",
      "basis": "Risk gradation",
      "id": "3-levels-zone-0-1-2-system-attribute-2-levels-div-1-div-2",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/3-levels-zone-0-1-2-system-attribute-2-levels-div-1-div-2/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Risk gradation | 2 levels (Div 1, Div 2) | 3 levels (Zone 0, 1, 2) | 3 levels (Zone 0, 1, 2)",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "area classification",
      "north_american_designation": "Class III",
      "basis": "Ignitable fibers",
      "id": "area-classification-class-iii",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/area-classification-class-iii/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Class III | Ignitable fibers",
      "verified_fields": [
        "basis",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "system attribute",
      "north_american_designation": "NEC 500 (Class/Division)",
      "iec_designation": "ATEX / IECEx (Zone)",
      "basis": "Geographic use: USA, Canada vs EU, UK, most of the world",
      "id": "atex-iecex-zone-system-attribute-nec-500-class-division",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/atex-iecex-zone-system-attribute-nec-500-class-division/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Geographic use | USA, Canada | USA, Canada | EU, UK, most of the world",
      "verified_fields": [
        "basis"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "dust group",
      "north_american_designation": "Class II, Group G",
      "basis": "Grain, flour, plastic dusts",
      "id": "dust-group-class-ii-group-g",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/dust-group-class-ii-group-g/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "Class II, Group G",
      "verified_fields": [
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "system attribute",
      "north_american_designation": "NFPA 70 (adopted by AHJs)",
      "iec_designation": "EU Directive 2014/34/EU / IECEx scheme",
      "basis": "Legal framework",
      "id": "eu-directive-2014-34-eu-iecex-scheme-system-attribute-nfpa-70-adopted-by-ahjs",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/eu-directive-2014-34-eu-iecex-scheme-system-attribute-nfpa-70-adopted-by-ahjs/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Legal framework | NFPA 70 (adopted by AHJs) | NFPA 70 (adopted by AHJs) | EU Directive 2014/34/EU / IECEx scheme",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "protection concept",
      "north_american_designation": "Explosion-proof (XP)",
      "iec_designation": "Ex d (Flameproof)",
      "iec_standard": "IEC 60079-1",
      "basis": "Contain the explosion inside the enclosure",
      "id": "ex-d-flameproof-protection-concept-explosion-proof-xp",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/ex-d-flameproof-protection-concept-explosion-proof-xp/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Explosion-proof (XP) | Ex d (Flameproof) | IEC 60079-1 | Contain the explosion inside the enclosure",
      "verified_fields": [
        "basis",
        "iec_designation",
        "iec_standard",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "protection concept",
      "north_american_designation": "Flameproof enclosure",
      "iec_designation": "Ex d",
      "basis": "Flameproof enclosure",
      "id": "ex-d-protection-concept-flameproof-enclosure",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/ex-d-protection-concept-flameproof-enclosure/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Ex d | Flameproof enclosure",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "protection concept",
      "north_american_designation": "Increased safety",
      "iec_designation": "Ex e",
      "basis": "Increased safety",
      "id": "ex-e-protection-concept-increased-safety",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/ex-e-protection-concept-increased-safety/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Ex e | Increased safety",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "protection concept",
      "north_american_designation": "Intrinsically Safe (IS)",
      "iec_designation": "Ex i (Ex ia, Ex ib)",
      "iec_standard": "IEC 60079-11",
      "basis": "Limit energy below ignition threshold",
      "id": "ex-i-ex-ia-ex-ib-protection-concept-intrinsically-safe-is",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/ex-i-ex-ia-ex-ib-protection-concept-intrinsically-safe-is/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Intrinsically Safe (IS) | Ex i (Ex ia, Ex ib) | IEC 60079-11 | Limit energy below ignition threshold",
      "verified_fields": [
        "basis",
        "iec_designation",
        "iec_standard",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "protection concept",
      "north_american_designation": "Intrinsically Safe",
      "iec_designation": "Ex i",
      "basis": "Intrinsic safety",
      "id": "ex-i-protection-concept-intrinsically-safe",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/ex-i-protection-concept-intrinsically-safe/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Ex i | Intrinsic safety",
      "verified_fields": [
        "basis",
        "iec_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "protection concept",
      "north_american_designation": "Encapsulation",
      "iec_designation": "Ex m",
      "basis": "Encapsulation",
      "id": "ex-m-protection-concept-encapsulation",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/ex-m-protection-concept-encapsulation/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Ex m | Encapsulation",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "protection concept",
      "north_american_designation": "Non-incendive",
      "iec_designation": "Ex nA / Ex ec",
      "iec_standard": "IEC 60079-15 / -7",
      "basis": "Normal operation cannot cause ignition",
      "id": "ex-na-ex-ec-protection-concept-non-incendive",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/ex-na-ex-ec-protection-concept-non-incendive/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Non-incendive | Ex nA / Ex ec | IEC 60079-15 / -7 | Normal operation cannot cause ignition",
      "verified_fields": [
        "basis",
        "iec_designation",
        "iec_standard",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "protection concept",
      "north_american_designation": "Hermetically sealed",
      "iec_designation": "Ex nC / Ex m",
      "iec_standard": "IEC 60079-15 / -18",
      "basis": "Seal ignition source from atmosphere",
      "id": "ex-nc-ex-m-protection-concept-hermetically-sealed",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/ex-nc-ex-m-protection-concept-hermetically-sealed/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Hermetically sealed | Ex nC / Ex m | IEC 60079-15 / -18 | Seal ignition source from atmosphere",
      "verified_fields": [
        "basis",
        "iec_designation",
        "iec_standard",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "protection concept",
      "north_american_designation": "Purged/Pressurized",
      "iec_designation": "Ex p (Ex px, Ex py, Ex pz)",
      "iec_standard": "IEC 60079-2",
      "basis": "Maintain positive pressure with inert gas",
      "id": "ex-p-ex-px-ex-py-ex-pz-protection-concept-purged-pressurized",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/ex-p-ex-px-ex-py-ex-pz-protection-concept-purged-pressurized/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Purged/Pressurized | Ex p (Ex px, Ex py, Ex pz) | IEC 60079-2 | Maintain positive pressure with inert gas",
      "verified_fields": [
        "basis",
        "iec_designation",
        "iec_standard",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "protection concept",
      "north_american_designation": "Pressurization",
      "iec_designation": "Ex p",
      "basis": "Pressurization",
      "id": "ex-p-protection-concept-pressurization",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/ex-p-protection-concept-pressurization/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Ex p | Pressurization",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "protection concept",
      "north_american_designation": "Dust-ignition-proof",
      "iec_designation": "Ex t (Dust protection by enclosure)",
      "iec_standard": "IEC 60079-31",
      "basis": "Prevent dust ingress and limit surface temperature",
      "id": "ex-t-dust-protection-by-enclosure-protection-concept-dust-ignition-proof",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/ex-t-dust-protection-by-enclosure-protection-concept-dust-ignition-proof/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Dust-ignition-proof | Ex t (Dust protection by enclosure) | IEC 60079-31 | Prevent dust ingress and limit surface temperature",
      "verified_fields": [
        "basis",
        "iec_designation",
        "iec_standard",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "gas group",
      "north_american_designation": "Group E",
      "basis": "Metal dust",
      "id": "gas-group-group-e",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/gas-group-group-e/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "E | Metal dust",
      "verified_fields": [
        "basis"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "gas group",
      "north_american_designation": "Group F",
      "basis": "Carbon dust",
      "id": "gas-group-group-f",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/gas-group-group-f/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "F | Carbon dust",
      "verified_fields": [
        "basis"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "gas group",
      "north_american_designation": "Group G",
      "basis": "Grain / flour dust",
      "id": "gas-group-group-g",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/gas-group-group-g/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "G | Grain / flour dust",
      "verified_fields": [
        "basis"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "system attribute",
      "north_american_designation": "Groups A, B, C, D",
      "iec_designation": "Groups IIC, IIB, IIA",
      "basis": "Gas classification",
      "id": "groups-iic-iib-iia-system-attribute-groups-a-b-c-d",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/groups-iic-iib-iia-system-attribute-groups-a-b-c-d/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Gas classification | Groups A, B, C, D | Groups IIC, IIB, IIA | Groups IIC, IIB, IIA",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "system attribute",
      "north_american_designation": "Explosion-proof (XP), intrinsically safe (IS)",
      "iec_designation": "IEC-aligned types (Ex d, Ex i, Ex e, etc.)",
      "basis": "Protection concept",
      "id": "iec-aligned-types-ex-d-ex-i-ex-e-etc-system-attribute-explosion-proof-xp-intrinsically-safe-is",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iec-aligned-types-ex-d-ex-i-ex-e-etc-system-attribute-explosion-proof-xp-intrinsically-safe-is/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Protection concept | Explosion-proof (XP), intrinsically safe (IS) | IEC-aligned types (Ex d, Ex i, etc.) | IEC-aligned types (Ex d, Ex i, Ex e, etc.)",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "gas group",
      "north_american_designation": "Class I, Group D",
      "iec_designation": "IIA",
      "basis": "Propane",
      "id": "iia-gas-group-class-i-group-d",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iia-gas-group-class-i-group-d/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "IIA | Propane | Class I, Group D |",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "gas group",
      "north_american_designation": "Group D",
      "iec_designation": "IIA",
      "basis": "MESG >0.90 mm",
      "id": "iia-gas-group-group-d",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iia-gas-group-group-d/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "D | IIA | Methane, propane, gasoline | >0.90 mm",
      "verified_fields": [
        "iec_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "disagreements": [
        {
          "field": "basis",
          "versions": [
            {
              "value": "MESG >0.90 mm",
              "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
              "source_quote": "D | IIA | Methane, propane, gasoline | >0.90 mm",
              "as_of": "2026-08-06"
            },
            {
              "value": "Gasoline",
              "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
              "source_quote": "Gasoline | D | 280 | 536 | 600 PSI | IIA",
              "as_of": "2026-08-06"
            },
            {
              "value": "Propane",
              "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
              "source_quote": "D (Propane) | IIA",
              "as_of": "2026-08-06"
            }
          ]
        }
      ]
    },
    {
      "category": "gas group",
      "north_american_designation": "Class I, Group C",
      "iec_designation": "IIB",
      "basis": "Ethylene",
      "id": "iib-gas-group-class-i-group-c",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iib-gas-group-class-i-group-c/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "IIB | Ethylene | Class I, Group C | Ethylene",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "gas group",
      "north_american_designation": "Group C",
      "iec_designation": "IIB",
      "basis": "MESG 0.50\u20130.90 mm",
      "id": "iib-gas-group-group-c",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iib-gas-group-group-c/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "C | IIB | Ethylene, ethyl ether | 0.50\u20130.90 mm",
      "verified_fields": [
        "iec_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "disagreements": [
        {
          "field": "basis",
          "versions": [
            {
              "value": "MESG 0.50\u20130.90 mm",
              "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
              "source_quote": "C | IIB | Ethylene, ethyl ether | 0.50\u20130.90 mm",
              "as_of": "2026-08-06"
            },
            {
              "value": "Ethylene",
              "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
              "source_quote": "Ethylene | C | 450 | 842 | 1,200 PSI | IIB",
              "as_of": "2026-08-06"
            }
          ]
        }
      ]
    },
    {
      "category": "gas group",
      "north_american_designation": "Class I, Group B",
      "iec_designation": "IIB + H2",
      "basis": "Hydrogen",
      "id": "iib-h2-gas-group-class-i-group-b",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iib-h2-gas-group-class-i-group-b/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "IIB + H 2 | Hydrogen | Class I, Group B | Hydrogen",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "gas group",
      "north_american_designation": "Class I, Group A",
      "iec_designation": "IIC",
      "basis": "Acetylene",
      "id": "iic-gas-group-class-i-group-a",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iic-gas-group-class-i-group-a/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "IIC | Acetylene | Class I, Group A | Acetylene",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "gas group",
      "north_american_designation": "Group A",
      "iec_designation": "IIC",
      "basis": "MESG <0.50 mm",
      "id": "iic-gas-group-group-a",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iic-gas-group-group-a/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "A | IIC | Acetylene | <0.50 mm",
      "verified_fields": [
        "iec_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "disagreements": [
        {
          "field": "basis",
          "versions": [
            {
              "value": "MESG <0.50 mm",
              "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
              "source_quote": "A | IIC | Acetylene | <0.50 mm",
              "as_of": "2026-08-06"
            },
            {
              "value": "Acetylene",
              "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
              "source_quote": "Acetylene | A | 305 | 581 | 6,000 PSI | IIC",
              "as_of": "2026-08-06"
            }
          ]
        }
      ]
    },
    {
      "category": "gas group",
      "north_american_designation": "Group B",
      "iec_designation": "IIC",
      "basis": "Hydrogen",
      "id": "iic-gas-group-group-b",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iic-gas-group-group-b/",
      "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
      "source_quote": "Hydrogen | B | 520 | 968 | 6,000 PSI | IIC",
      "verified_fields": [
        "basis",
        "iec_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "gas group",
      "north_american_designation": "Group B",
      "iec_designation": "IIC (partially IIB+H\u2082)",
      "basis": "MESG <0.50 mm",
      "id": "iic-partially-iib-h-gas-group-group-b",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iic-partially-iib-h-gas-group-group-b/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "B | IIC (partially IIB+H\u2082) | Hydrogen, butadiene | <0.50 mm",
      "verified_fields": [
        "iec_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "dust group",
      "north_american_designation": "Class III",
      "iec_designation": "IIIA",
      "basis": "Fibers and flyings",
      "id": "iiia-dust-group-class-iii",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iiia-dust-group-class-iii/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "Gas / dust group | Typical Substances | IIC | Acetylene | Class I, Group A | Acetylene | IIB + H 2 | Hydrogen | Class I, Group B | Hydrogen | IIB | Ethylene | Class I, Group C | Ethylene | IIA | Propane | Class I, Group D | Propane | IIIC | Conductive dust | Class II, Group E | Combustible metal dust | IIIB | Non-conductive dust | Class II, Group F | Combustible carbonaceous dust | Class II, Group G | Combustible dusts not in group E or F | IIIA | Combustible flyings | Class III |",
      "verified_fields": [
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "dust group",
      "north_american_designation": "Class II, Group F",
      "iec_designation": "IIIB",
      "basis": "Carbon dusts",
      "id": "iiib-dust-group-class-ii-group-f",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iiib-dust-group-class-ii-group-f/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "Gas / dust group | Typical Substances | IIC | Acetylene | Class I, Group A | Acetylene | IIB + H 2 | Hydrogen | Class I, Group B | Hydrogen | IIB | Ethylene | Class I, Group C | Ethylene | IIA | Propane | Class I, Group D | Propane | IIIC | Conductive dust | Class II, Group E | Combustible metal dust | IIIB | Non-conductive dust | Class II, Group F |",
      "verified_fields": [
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "dust group",
      "north_american_designation": "Class II, Group E",
      "iec_designation": "IIIC",
      "basis": "Metal dusts",
      "id": "iiic-dust-group-class-ii-group-e",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/iiic-dust-group-class-ii-group-e/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "Gas / dust group | Typical Substances | IIC | Acetylene | Class I, Group A | Acetylene | IIB + H 2 | Hydrogen | Class I, Group B | Hydrogen | IIB | Ethylene | Class I, Group C | Ethylene | IIA | Propane | Class I, Group D | Propane | IIIC | Conductive dust | Class II, Group E |",
      "verified_fields": [
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "system attribute",
      "north_american_designation": "NRTLs (UL, FM, CSA)",
      "iec_designation": "Notified Bodies (ATEX) / ExCBs (IECEx)",
      "basis": "Certification body",
      "id": "notified-bodies-atex-excbs-iecex-system-attribute-nrtls-ul-fm-csa",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/notified-bodies-atex-excbs-iecex-system-attribute-nrtls-ul-fm-csa/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Certification body | NRTLs (UL, FM, CSA) | NRTLs | Notified Bodies (ATEX) / ExCBs (IECEx)",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "temperature code",
      "north_american_designation": "T1",
      "iec_designation": "T1",
      "max_surface_temperature_c": "450",
      "basis": "Ignition temperature of gas / dust >450",
      "id": "t1-temperature-code-t1",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/t1-temperature-code-t1/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "450 | T1 | >450",
      "verified_fields": [
        "iec_designation",
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "842",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T1 | T1 | 450 | 842",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T2",
      "iec_designation": "T2",
      "max_surface_temperature_c": "300",
      "basis": "Ignition temperature of gas / dust >300-450",
      "id": "t2-temperature-code-t2",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/t2-temperature-code-t2/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "300 | T2 | >300-450",
      "verified_fields": [
        "iec_designation",
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "572",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T2 | T2 | 300 | 572",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T3",
      "iec_designation": "T3",
      "max_surface_temperature_c": "200",
      "basis": "Ignition temperature of gas / dust >200-300",
      "id": "t3-temperature-code-t3",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/t3-temperature-code-t3/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "200 | T3 | >200-300",
      "verified_fields": [
        "iec_designation",
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "392",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T3 | T3 | 200 | 392",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T4",
      "iec_designation": "T4",
      "max_surface_temperature_c": "135",
      "basis": "Ignition temperature of gas / dust >135-200",
      "id": "t4-temperature-code-t4",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/t4-temperature-code-t4/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "135 | T4 | >135-200",
      "verified_fields": [
        "iec_designation",
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "275",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T4 | T4 | 135 | 275",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T5",
      "iec_designation": "T5",
      "max_surface_temperature_c": "100",
      "basis": "Ignition temperature of gas / dust >100-135",
      "id": "t5-temperature-code-t5",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/t5-temperature-code-t5/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "100 | T5 | >100-135",
      "verified_fields": [
        "iec_designation",
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "212",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T5 | T5 | 100 | 212",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T6",
      "iec_designation": "T6",
      "max_surface_temperature_c": "85",
      "basis": "Ignition temperature of gas / dust >85-100",
      "id": "t6-temperature-code-t6",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/t6-temperature-code-t6/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "85 | T6 | >85-100",
      "verified_fields": [
        "iec_designation",
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "185",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T6 | T6 | 85 | 185",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T2A",
      "max_surface_temperature_c": "280",
      "basis": "Ignition temperature of gas / dust >280-300",
      "id": "temperature-code-t2a",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/temperature-code-t2a/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "280 | T2A | >280-300",
      "verified_fields": [
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "536",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T2A | | 280 | 536",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T2B",
      "max_surface_temperature_c": "260",
      "basis": "Ignition temperature of gas / dust >260-280",
      "id": "temperature-code-t2b",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/temperature-code-t2b/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "260 | T2B | >260-280",
      "verified_fields": [
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "500",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T2B | | 260 | 500",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T2C",
      "max_surface_temperature_c": "230",
      "basis": "Ignition temperature of gas / dust >230-260",
      "id": "temperature-code-t2c",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/temperature-code-t2c/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "230 | T2C | >230-260",
      "verified_fields": [
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "446",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T2C | | 230 | 446",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T2D",
      "max_surface_temperature_c": "215",
      "basis": "Ignition temperature of gas / dust >215-230",
      "id": "temperature-code-t2d",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/temperature-code-t2d/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "215 | T2D | >215-230",
      "verified_fields": [
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "419",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T2D | | 215 | 419",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T3A",
      "max_surface_temperature_c": "180",
      "basis": "Ignition temperature of gas / dust >180-200",
      "id": "temperature-code-t3a",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/temperature-code-t3a/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "180 | T3A | >180-200",
      "verified_fields": [
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "356",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T3A | | 180 | 356",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T3B",
      "max_surface_temperature_c": "165",
      "basis": "Ignition temperature of gas / dust >165-180",
      "id": "temperature-code-t3b",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/temperature-code-t3b/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "165 | T3B | >165-180",
      "verified_fields": [
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "329",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T3B | | 165 | 329",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T3C",
      "max_surface_temperature_c": "160",
      "basis": "Ignition temperature of gas / dust >160-165",
      "id": "temperature-code-t3c",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/temperature-code-t3c/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "160 | T3C | >160-165",
      "verified_fields": [
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "320",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T3C | | 160 | 320",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "temperature code",
      "north_american_designation": "T4A",
      "max_surface_temperature_c": "120",
      "basis": "Ignition temperature of gas / dust >120-135",
      "id": "temperature-code-t4a",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/temperature-code-t4a/",
      "source": "https://www.e2s.com/guide-for-hazardous-areas/gas-and-dust-groups",
      "source_quote": "120 | T4A | >120-135",
      "verified_fields": [
        "max_surface_temperature_c",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ],
      "also_reported": [
        {
          "field": "max_surface_temperature_f",
          "value": "248",
          "source": "https://ldpi-inc.com/resources/classification-codes/class-1-locations/",
          "source_quote": "T4A | | 120 | 248",
          "as_of": "2026-08-06"
        }
      ],
      "disagreements": []
    },
    {
      "category": "area classification",
      "north_american_designation": "Class I",
      "iec_designation": "Zone 0, 1, 2 (gas)",
      "basis": "Flammable gases and vapors",
      "id": "zone-0-1-2-gas-area-classification-class-i",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-0-1-2-gas-area-classification-class-i/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Class I | Flammable gases and vapors",
      "verified_fields": [
        "basis",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "system attribute",
      "north_american_designation": "Class I (gas), II (dust), III (fibers)",
      "iec_designation": "Zone 0, 1, 2 (gas); Zone 20, 21, 22 (dust)",
      "basis": "Hazard basis",
      "id": "zone-0-1-2-gas-zone-20-21-22-dust-system-attribute-class-i-gas-ii-dust-iii-fibers",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-0-1-2-gas-zone-20-21-22-dust-system-attribute-class-i-gas-ii-dust-iii-fibers/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Hazard basis | Class I (gas), II (dust), III (fibers) | Zone 0, 1, 2 (gas only) | Zone 0, 1, 2 (gas); Zone 20, 21, 22 (dust)",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "area classification",
      "north_american_designation": "Class I Division 1",
      "iec_designation": "Zone 0",
      "basis": "Continuous hazard",
      "id": "zone-0-area-classification-class-i-division-1",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-0-area-classification-class-i-division-1/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Continuous hazard | Class I Division 1 | Zone 0",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "area classification",
      "north_american_designation": "(no NEC 500 equivalent)",
      "iec_designation": "Zone 0",
      "basis": "Explosive atmosphere continuously or for long periods (>1000 hrs/yr)",
      "id": "zone-0-area-classification-no-nec-500-equivalent",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-0-area-classification-no-nec-500-equivalent/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Zone 0 | Explosive atmosphere continuously or for long periods (>1000 hrs/yr)",
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        "basis",
        "iec_designation"
      ],
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    {
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      "basis": "Explosive atmosphere present continuously or for long periods",
      "id": "zone-0-area-classification-no-nec-equivalent",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-0-area-classification-no-nec-equivalent/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Zone 0 | Explosive atmosphere present continuously or for long periods",
      "verified_fields": [
        "basis",
        "iec_designation"
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      "derived_fields": [
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    {
      "category": "area classification",
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      "iec_designation": "Zone 0 / Zone 1",
      "basis": "Hazard present during normal operation",
      "id": "zone-0-zone-1-area-classification-division-1",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-0-zone-1-area-classification-division-1/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Division 1 | Hazard present during normal operation",
      "verified_fields": [
        "basis",
        "north_american_designation"
      ],
      "derived_fields": [
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    },
    {
      "category": "area classification",
      "north_american_designation": "Class I Division 1",
      "iec_designation": "Zone 1",
      "basis": "Frequent hazard",
      "id": "zone-1-area-classification-class-i-division-1",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-1-area-classification-class-i-division-1/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Frequent hazard | Class I Division 1 | Zone 1",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
      ],
      "derived_fields": [
        "category"
      ]
    },
    {
      "category": "area classification",
      "north_american_designation": "(no NEC equivalent)",
      "iec_designation": "Zone 1",
      "basis": "Explosive atmosphere likely during normal operation",
      "id": "zone-1-area-classification-no-nec-equivalent",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-1-area-classification-no-nec-equivalent/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Zone 1 | Explosive atmosphere likely during normal operation",
      "verified_fields": [
        "basis",
        "iec_designation"
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    },
    {
      "category": "area classification",
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      "iec_designation": "Zone 1 (+ Zone 0)",
      "basis": "Explosive atmosphere likely during normal operation (10\u20131000 hrs/yr)",
      "id": "zone-1-zone-0-area-classification-division-1",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-1-zone-0-area-classification-division-1/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Division 1 | Zone 1 (+ Zone 0) | Explosive atmosphere likely during normal operation (10\u20131000 hrs/yr)",
      "verified_fields": [
        "basis",
        "iec_designation",
        "north_american_designation"
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    },
    {
      "category": "area classification",
      "north_american_designation": "Class I Division 2",
      "iec_designation": "Zone 2",
      "basis": "Occasional hazard",
      "id": "zone-2-area-classification-class-i-division-2",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-2-area-classification-class-i-division-2/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Occasional hazard | Class I Division 2 | Zone 2",
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        "basis",
        "iec_designation",
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    {
      "category": "area classification",
      "north_american_designation": "Division 2",
      "iec_designation": "Zone 2",
      "basis": "Explosive atmosphere not likely; only abnormal conditions (<10 hrs/yr)",
      "id": "zone-2-area-classification-division-2",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-2-area-classification-division-2/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Division 2 | Zone 2 | Explosive atmosphere not likely; only abnormal conditions (<10 hrs/yr)",
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        "basis",
        "iec_designation",
        "north_american_designation"
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              "value": "Explosive atmosphere not likely; only abnormal conditions (<10 hrs/yr)",
              "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
              "source_quote": "Division 2 | Zone 2 | Explosive atmosphere not likely; only abnormal conditions (<10 hrs/yr)",
              "as_of": "2026-08-06"
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            {
              "value": "Hazard present only under abnormal conditions",
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              "source_quote": "Division 2 | Hazard present only under abnormal conditions",
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      "category": "area classification",
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      "id": "zone-2-area-classification-no-nec-equivalent",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-2-area-classification-no-nec-equivalent/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Zone 2 | Explosive atmosphere unlikely in normal operation, only short duration eg. accidental leakage",
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      "source_quote": "Class II | Combustible dust",
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        "basis",
        "north_american_designation"
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      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-20-21-22-iiia-iiib-iiic-system-attribute-class-ii-groups-e-f-g/",
      "source": "https://exknowledge.com/pages/nec-500-vs-atex-iec.html",
      "source_quote": "Dust classification | Class II Groups E, F, G | Not covered | Zone 20, 21, 22 (IIIA, IIIB, IIIC)",
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        "iec_designation",
        "north_american_designation"
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      "category": "area classification",
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      "id": "zone-20-area-classification-no-nec-equivalent",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-20-area-classification-no-nec-equivalent/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Zone 20 | Combustible dust present continuously",
      "verified_fields": [
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        "iec_designation"
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      "category": "area classification",
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      "id": "zone-21-area-classification-no-nec-equivalent",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-21-area-classification-no-nec-equivalent/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Zone 21 | Dust likely during normal operation",
      "verified_fields": [
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        "iec_designation"
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      "category": "area classification",
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      "basis": "Dust unlikely except briefly",
      "id": "zone-22-area-classification-no-nec-equivalent",
      "url": "https://referencesource.org/ex-classification-system-crosswalk/zone-22-area-classification-no-nec-equivalent/",
      "source": "https://www.inframena.com/hazardous-area-classification-equivalency-guide/",
      "source_quote": "Zone 22 | Dust unlikely except briefly",
      "verified_fields": [
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