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CSA C22.2 No. 166‑15: Surface Metal Raceways and Fittings – Technical Overview and Compliance Guide
Understanding the Canadian Standard for the Safety, Construction, and Installation of Surface Metal Raceway Systems
Scope of CSA C22.2 No. 166‑15
CSA C22.2 No. 166‑15 applies to surface metal raceways (SMRs) and their associated fittings intended for use in accordance with the Canadian Electrical Code, Part I (CE Code). The standard covers:
- Metal raceways of either steel or aluminum construction, including channels, covers, and joining accessories.
- Fittings such as connectors, couplings, elbows, tees, boxes, and covers designed specifically for use with surface metal raceways.
- Accessories including mounting brackets, support clips, and closure strips.
The standard does not apply to raceways intended for use in hazardous locations unless separately certified to the appropriate requirements (e.g., CSA C22.2 No. 30). Surface metal raceways covered by this standard are rated for a maximum of 300 V and are intended for dry locations only.
Technical Requirements
Materials and Construction
Raceways must be constructed from corrosion‑resistant steel or aluminum. Minimum thicknesses are specified to ensure mechanical strength during installation and service.
| Material | Raceway Type | Minimum Thickness (mm) |
|---|---|---|
| Steel (galvanized or painted) | Raceway body | 1.07 |
| Steel | Raceway cover | 0.79 |
| Aluminum (bare or coated) | Raceway body | 1.27 |
| Aluminum | Raceway cover | 0.91 |
All metallic parts shall be made of materials that resist corrosion. Steel components must be galvanized or otherwise coated to prevent rusting. Edges and corners must be rounded or deburred to protect conductor insulation during cable pulling.
Mechanical Strength and Impact Resistance
Raceways and fittings are subjected to impact, bending, and load tests to verify they can withstand the stresses encountered in normal installation and use. A steel ball (~5 kg) dropped from a specified height must not cause visible cracking or deformation that reduces the raceway interior cross‑section by more than 10 %.
Electrical Continuity and Bonding
Raceway systems must provide a reliable path for fault current. Joints and connections shall maintain electrical continuity with a resistance not exceeding 0.01 Ω after the pull‑out test. Dedicated bonding jumpers are required when non‑conductive gaskets or coatings interrupt metallic contact.
Marking Requirements
Each raceway section and fitting shall be permanently marked with:
- Manufacturer’s name, trademark, or logo
- Catalog or model number
- CSA certification mark or report number
- Maximum voltage rating (300 V)
- Maximum temperature rating if applicable
Tip: Always verify that the raceway marking includes the CSA certification mark. Unmarked or incorrectly marked products should be rejected to avoid compliance issues during inspection.
Implementation Highlights
Installation Practices
Surface metal raceways are intended to be mounted directly on walls, ceilings, or other surfaces without the need for a separate structural support system. The standard does not prescribe specific support spacing; however, installers must follow the manufacturer’s instructions and the CE Code (Section 12).
- Raceway runs must be continuous between boxes or fittings.
- Maximum support intervals should be chosen to prevent sagging – typically every 1.5 m for horizontal runs.
- Covers must be securely fastened to the base channel.
- Fittings must be listed for use with the specific raceway brand.
Field Modifications
Cutting, drilling, and bending of raceway sections are permitted as long as the resulting finish is smooth and the corrosion protection is restored on cut edges. Use of a bonding jumper may be required when a section is interrupted by a non‑metallic insulator.
Good Practice: To ensure reliable bonding, clean paint and oxide from joining surfaces before assembly. Use listed bonding clips or jumpers where the manufacturer recommends them.
Caution: Do not mix raceway brands or types without verifying compatibility. Using a fitting from a different manufacturer may void the certification and compromise electrical continuity.
Compliance Notes and Certification
Certification to CSA C22.2 No. 166‑15
In Canada, surface metal raceways are required to be certified to a recognized standard. CSA C22.2 No. 166‑15 is the prevailing standard and is referenced by the CE Code. Certification is performed by accredited organizations such as CSA Group, Underwriters Laboratories (UL), or Intertek (ETL).
Field Evaluation
Products that have not been third‑party certified may be subject to field evaluation by a local authority having jurisdiction (AHJ). Field labeling is possible but often more costly and time‑consuming than factory certification.
Important: Use of non‑certified raceway systems may lead to failure of an electrical inspection, insurance liability issues, and voiding of warranties. Always insist on products bearing a recognized certification mark.
Updating from Previous Editions
The 2015 edition of this standard introduced tighter impact test criteria, revised markings for high‑temperature environments, and clarified bonding requirements for raceways with non‑conductive covers. Manufacturers should review their product lines to ensure continued compliance, and installers should check that the installed raceway meets the edition adopted by the local CE Code.
Frequently Asked Questions
Q: What is the voltage rating of surface metal raceways covered by CSA C22.2 No. 166‑15?
A: The standard covers raceways rated for a maximum of 300 V. These systems are intended for use in dry locations only and are commonly used for power and communication wiring in commercial and residential spaces.
A: The standard covers raceways rated for a maximum of 300 V. These systems are intended for use in dry locations only and are commonly used for power and communication wiring in commercial and residential spaces.
Q: Can surface metal raceways be installed in wet or outdoor locations?
A: No, CSA C22.2 No. 166‑15 explicitly limits the scope to dry locations. For outdoor or wet environments, refer to standards for liquid‑tight flexible metal conduit (CSA C22.2 No. 250) or galvanized rigid steel conduit (CSA C22.2 No. 45).
A: No, CSA C22.2 No. 166‑15 explicitly limits the scope to dry locations. For outdoor or wet environments, refer to standards for liquid‑tight flexible metal conduit (CSA C22.2 No. 250) or galvanized rigid steel conduit (CSA C22.2 No. 45).
Q: Do I need a bonding jumper when connecting two sections of raceway?
A: Electrical continuity must be maintained across all joints. If the manufacturer’s fittings provide a low‑impedance metal‑to‑metal contact, a separate jumper is not required. However, when a non‑conductive gasket or coating interrupts the bond, a bonding jumper listed for the raceway must be installed.
A: Electrical continuity must be maintained across all joints. If the manufacturer’s fittings provide a low‑impedance metal‑to‑metal contact, a separate jumper is not required. However, when a non‑conductive gasket or coating interrupts the bond, a bonding jumper listed for the raceway must be installed.
Q: How often should raceway supports be placed?
A: The standard does not specify support spacing; instead, the installer must follow the manufacturer’s instructions and the CE Code (Rule 12‑1300). In practice, horizontal raceways are supported every 1.5 m and vertical runs at each end, with intermediate supports as needed to prevent movement.
A: The standard does not specify support spacing; instead, the installer must follow the manufacturer’s instructions and the CE Code (Rule 12‑1300). In practice, horizontal raceways are supported every 1.5 m and vertical runs at each end, with intermediate supports as needed to prevent movement.
Technical article – CSA C22.2 No. 166‑15 last revised in 2015. This content is based on the 2015 edition. Always consult the latest published standard and local adoption for current requirements. © 2026