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CSA C22.2 No. 198.3-05 (2014): Safety Standard for Plugs and Receptacles in Hazardous Locations
Technical Overview and Compliance for Class I Zone 2 and Class II Zone 22 Connectors
CSA C22.2 No. 198.3-05 (2014) is a Canadian national standard developed under the auspices of the CSA Group, part of the comprehensive CSA C22.2 series of safety standards for electrical equipment. This standard specifies safety requirements for plugs, receptacles, cord connectors, inlets, and couplers intended for use in hazardous locations where flammable gases, vapors, or combustible dusts may be present under normal operation. Specifically, it covers equipment suitable for Class I, Zone 2 (gas/vapor) and Class II, Zone 22 (dust) hazardous locations, as defined by the Canadian Electrical Code (CEC). The standard was originally published in 2005 and reaffirmed without change in 2014, and it remains current as of the 2026 edition of the CEC.
This article provides a detailed overview of the scope, technical requirements, implementation considerations, and compliance aspects of CSA C22.2 No. 198.3-05 (2014). It is intended for electrical engineers, safety professionals, specifiers, and installers working with electrical equipment in hazardous environments.
Scope and Application
CSA C22.2 No. 198.3 applies to plugs, receptacles, cord couplers, appliance couplers, and other similar connecting devices that are intended to be used in hazardous locations classified as Class I, Zone 2 or Class II, Zone 22. These locations are characterized by the infrequent presence of flammable substances under abnormal conditions. Equipment covered is limited to single- or multi-pole connectors rated not exceeding 600 V AC or DC, and with current ratings typically up to 200 A.
The standard covers both non-interlocked and interlocked types, where interlocking may be required in certain hazardous area applications to prevent disconnection under load. The equipment is intended for use with flexible cable or cord, and may be provided with a means for wiring or for direct connection to an industrial plug or receptacle.
The following table summarizes the typical classifications and ratings for connectors under this standard.
| Classification | Zone | Gas/Dust Group | Max. Voltage | Max. Current | Min. IP Protection | Temperature Class (T-Code) |
|---|---|---|---|---|---|---|
| Class I | Zone 2 | IIA, IIB, IIC | 600 V | 200 A | IP54 | T1–T6 (≤85°C for T6) |
| Class II | Zone 22 | IIIA, IIIB, IIIC | 600 V | 200 A | IP6X | T1–T6 (≤85°C for T6) |
Tip: When selecting a connector, ensure that its temperature class (T-code) is less than the autoignition temperature of the specific gas or dust present. Also verify that the ingress protection (IP) rating is suitable for both the zone and any additional environmental conditions (e.g., outdoor exposure, washdown).
Technical Requirements and Testing
The safety of connectors under CSA C22.2 No. 198.3-05 is ensured through a series of mandatory construction and performance requirements. These requirements are verified by type testing conducted by an accredited certification body. Key technical requirements include:
Construction
- Materials: Continuous use insulating parts must be of material with satisfactory resistance to tracking (Comparative Tracking Index per IEC 60112). Conductive parts must be corrosion‑resistant, typically of copper or copper alloy.
- Creepage and Clearance: Distances must comply with the values suitable for the working voltage and pollution degree, as specified in the standard (typically >3 mm for 600 V working voltage).
- Ingress Protection: Enclosures must achieve a minimum IP54 for gas Group II and IP6X for dust Group III applications. The IP rating must be verified by testing.
- Temperature Class: Maximum surface temperature under normal and abnormal conditions must not exceed the permissible T‑code limit. For T6, the maximum surface temperature must be ≤85°C.
- Mechanical Strength: Connectors must withstand impact, crushing, and bending tests without impairing safety. Strain relief must be provided for cable terminations.
- Interlocking: If required by the installation code, the connector must have an interlock that prevents insertion or withdrawal when the circuit is energized, unless the connector is rated for make/break under load.
Electrical Performance
- Dielectric Voltage Withstand: A test voltage of 2.5 kV (or 1 kV for low‑voltage circuits) applied for 60 s between live parts and grounded parts.
- Insulation Resistance: Not less than 5 MΩ at 500 V DC after humidity conditioning.
- Temperature Rise: Under rated current, temperature rise measured on terminals and external parts must not exceed specified limits (e.g., 45°C rise for copper terminals).
- Endurance: The connector must withstand ≥1000 cycles of operation at rated current (or at rated voltage and power factor for AC) without electrical or mechanical failure.
- Short‑Circuit Withstand: If marked with a short‑current rating, the connector must pass a short‑circuit test at that rating without dangerous occurrences.
Warning: Even though a connector may be certified to this standard, it is essential to follow the manufacturer’s installation instructions and the CEC requirements for hazardous locations. Pay special attention to the correct selection of T‑code, IP rating, and the use of approved cable glands.
Compliance and Certification
In Canada, all electrical products for use in hazardous locations must be certified by an accredited certification organization (e.g., CSA Group, Intertek, UL). Certification to CSA C22.2 No. 198.3-05 is recognized by provincial authorities and referenced in Section 18 of the CEC. The certification process involves:
- Submission of product samples to an accredited test laboratory.
- Type testing according to all applicable clauses.
- Factory inspections to ensure quality control consistency.
- Marking of the product with the certification mark, product ratings, T‑code, IP code, and any special conditions of use.
Products certified to this standard may also be accepted in the United States under reciprocal recognition agreements, provided they also meet the requirements of UL 1686 (for Zone classification) or UL 1681 (for Division classification). For international use, the standard has many similarities with IEC 60079‑0 and IEC 60079‑7 (for equipment with increased safety “e” protection) and IEC 60079‑18 (for encapsulation “m”), but specific national differences exist. Some manufacturers may choose to obtain IECEx certification for global market access.
Success: Look for the CSA certification mark or a recognized NRTL mark on the product. This indicates that the connector has been independently verified to meet all safety requirements of CSA C22.2 No. 198.3-05 (2014) and is suitable for the intended hazardous location.
Danger: Never install a connector certified only for Zone 2/22 in a Zone 0/1 or Zone 20/21 area. The standard is strictly limited to infrequent presence of flammable substances. Using the wrong connector can lead to explosions and severe injury.
Frequently Asked Questions
Q: Does CSA C22.2 No. 198.3-05 cover connectors for Class I, Zone 1 hazardous locations?
A: No. This standard is limited to Zone 2 (gas/vapor) and Zone 22 (dust) only. For Zone 1 or Zone 21, refer to CSA C22.2 No. 198.1 or No. 198.2, or use equipment with explosion‑proof enclosures certified to other applicable standards.
A: No. This standard is limited to Zone 2 (gas/vapor) and Zone 22 (dust) only. For Zone 1 or Zone 21, refer to CSA C22.2 No. 198.1 or No. 198.2, or use equipment with explosion‑proof enclosures certified to other applicable standards.
Q: Can a connector certified to this standard be used in a Class I, Division 2 location (US system)?
A: Division classification is common in the United States, but it is not identical to Zone classification. While there is overlap, the Canadian standard is written for Zone designation. For installation in Canada, follow CEC Zone rules. For US installation, consult the National Electrical Code (NEC) and use a product certified to UL 1686 or UL 1203, as applicable.
A: Division classification is common in the United States, but it is not identical to Zone classification. While there is overlap, the Canadian standard is written for Zone designation. For installation in Canada, follow CEC Zone rules. For US installation, consult the National Electrical Code (NEC) and use a product certified to UL 1686 or UL 1203, as applicable.
Q: What is the maximum voltage and current that connectors under this standard can be rated for?
A: The standard typically covers connectors rated up to 600 V AC/DC and up to 200 A. However, manufacturers may choose to certify products for lower ratings. Always verify the exact marking on the product.
A: The standard typically covers connectors rated up to 600 V AC/DC and up to 200 A. However, manufacturers may choose to certify products for lower ratings. Always verify the exact marking on the product.
Q: Are interlocked connectors always required under this standard?
A: Not always. The standard permits non‑interlocked connectors if they are rated for make‑break under load and are used in circuits providing local disconnection. However, the CEC may require interlocking for specific installations, such as where unintentional disconnection could create a hazard. Always consult the local code authority for specific requirements.
A: Not always. The standard permits non‑interlocked connectors if they are rated for make‑break under load and are used in circuits providing local disconnection. However, the CEC may require interlocking for specific installations, such as where unintentional disconnection could create a hazard. Always consult the local code authority for specific requirements.
Reference year: 2026. This article is based on the reaffirmed standard CSA C22.2 No. 198.3-05 (2014) and the 2024 Canadian Electrical Code. For the most current information, consult the latest edition of the standard. © 2026 Technical Reference.