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HAZARDOUS AREAS · NORTH AMERICA

What Is Class 1 Division 2?

Class 1 Division 2, often written C1D2, is a North American hazardous location rating. Class 1 means flammable gases or vapours may be present; Division 2 means they are only expected under abnormal conditions, such as a leak or equipment failure. Equipment rated C1D2 will not ignite the atmosphere during normal operation.

01

The Short Answer

The system comes from the US National Electrical Code and the Canadian Electrical Code. Class II covers combustible dust and Class III fibres. Groups A to D set which gases a product is rated for, from acetylene (A) and hydrogen (B) to ethylene (C) and propane (D).

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    Division 1 Covers what the zone system splits into Zone 0 and Zone 1.
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    Division 2 Broadly matches Zone 2: hazards only under abnormal conditions.
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    Groups A, B, C, D Equipment rated for all four suits the widest range of gases.
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    Separate certification C1D2 and ATEX are separate approvals; one does not imply the other.
02

Why It Matters

Most C1D2 panel PCs are non-incendive rather than intrinsically safe; our intrinsically safe vs non-incendive FAQ explains the difference. The wastewater HMI case study shows a C1D2 HMI in use, and our hazardous area panel PCs cover the range.