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CSA C22.2 No. 39-13 (R2017): The Canadian Standard for Edison-Base Lampholder Safety
In-Depth Analysis of Scope, Technical Testing, and Certification for Screw-Shell Lampholders
Lampholders are the critical interface between a building’s electrical supply and its lighting sources. In Canada, the benchmark for these fundamental devices is CSA C22.2 No. 39-13 (R2017), a standard published by the CSA Group that has been reaffirmed to reflect ongoing industry consensus on safety. This standard, highly harmonized with UL 496, defines the precise safety, construction, and performance criteria for Edison-base (screw-shell) lampholders used in non-hazardous locations under the Canadian Electrical Code (CE Code), Part I.
Reaffirmed Consensus: The “R2017” suffix indicates that the standard was reviewed and reaffirmed by the technical committee, confirming its requirements remain current and valid for the industry.
1. Scope and Field of Application
CSA C22.2 No. 39-13 applies to lampholders of the screw-shell type (medium, intermediate, admedium, and mogul base sizes) intended for use with incandescent, LED, or other compatible lamps. The standard specifically covers:
- Construction Types: Keyless, pull-chain, push-through, and turn-knob switch lampholders, as well as wired lampholders.
- Ratings: Lampholders rated 600 V or less AC/DC.
- Hardware: Associated mounting means, screw shells, and center contacts.
The standard explicitly excludes lampholders designed for fluorescent lamps, pin-base or bayonet-base configurations, and any lampholders intended for use in hazardous (classified) locations, which are covered by the CSA C22.2 No. 60079 series.
CE Code Reference: Compliance with CSA C22.2 No. 39 is mandated by Section 30-104 of the Canadian Electrical Code, making it a legal requirement for all lampholders installed in Canada.
2. Core Construction and Performance Requirements
The standard sets forth rigorous material and design specifications to ensure safety and reliability over the product’s lifetime. Key technical requirements include:
Materials and Grounding
Current-carrying parts must be of copper, copper alloy, or other corrosion-resistant conductive metals. Metal lampholders must provide a reliable, low-impedance grounding path, complying with ground continuity tests. Insulating caps must be impact-resistant thermosetting or thermoplastic materials that do not distort under elevated temperatures.
Temperature Limits
Controlling operating temperature is critical to preventing fire hazards. The standard specifies maximum permissible temperatures under normal operating conditions, measured on the cap, shell, and internal contacts.
| Performance Factor | Medium Base | Mogul Base | Reference Clause |
|---|---|---|---|
| Maximum Cap Temperature | 90 °C | 90 °C | Clause 8 |
| Maximum Shell Temperature | 90 °C | 165 °C | Clause 8 |
| Maximum Contact Temperature | 210 °C | 210 °C | Clause 8 |
| Cap Torque Resistance | 2.3 N·m | 4.5 N·m | Clause 7 |
| Conductor Pullout Force | 89 N (20 lbf) | 89 N (20 lbf) | Clause 7 |
Strain Relief and Mechanical Integrity
For pendant lampholders, the standard requires that the wiring assembly withstand a direct pull of 89 N without slipping, cracking, or loosening the terminal connections. Switch mechanisms must withstand 6,000 cycles of operation without mechanical or electrical failure.
Implementation Consideration: When integrating a CSA-certified lampholder into a luminaire, designers must account for the thermal coupling effect. The lampholder’s temperature rise test results are valid only within the luminaire’s specified ambient temperature range.
3. Testing and Verification Protocols
CSA C22.2 No. 39 mandates a comprehensive battery of tests on representative samples. These tests ensure the lampholder can handle normal operation, environmental stress, and rare but dangerous edge cases.
Dielectric Voltage-Withstand Test
Following a 48-hour humidity conditioning cycle at 32 °C and 93% relative humidity, the lampholder must withstand a 60 Hz potential of 1,500 V (for 600 V rated holders) between live parts and accessible non-current-carrying metal parts without breakdown or flashover.
Temperature Rise in Normal Operation
The lampholder is operated at rated voltage and current in its intended mounting position (e.g., pendant, ceiling, wall) until equilibrium is reached. The standard limits the temperature of the cap and shell to prevent damage to the luminaire or adjacent building materials.
Abnormal Operation (End-of-Life Lamp Simulation)
This is a critical safety test that simulates the abrupt failure of an incandescent or discharge lamp. The lampholder must not:
- Emit molten metal or flaming particles.
- Ignite a surrounding gauze indicator.
- Allow a sustained flame to persist.
Hazardous Location Exclusion: Lampholders tested solely to C22.2 No. 39 are not certified for classified or hazardous locations. For explosive environments, compliance with the C22.2 No. 60079 series is required.
4. Certification and Compliance in the Canadian Market
Achieving compliance with CSA C22.2 No. 39 is a structured process managed by accredited certification bodies.
- Type Testing: Samples are submitted for the full suite of tests outlined in Sections 6 through 12 of the standard.
- Factory Inspection: The manufacturing facility is audited to verify quality control processes, material specifications, and traceability.
- Follow-up Program: Certified products are subject to periodic unannounced inspections and testing at the factory to ensure ongoing conformity.
Mandatory Marking
Each certified lampholder must be permanently and legibly marked with the following:
- The manufacturer’s name or registered trademark.
- A catalog number or type designation.
- Electrical ratings (volts, amperes, and wattage).
- The type of supply wire (e.g., “Use 90 °C wire”).
- The CSA certification monogram.
Harmonization Note: CSA C22.2 No. 39 is highly aligned with UL 496 in the United States. Manufacturers seeking access to both markets often pursue dual cULus certification through a single test program.
Frequently Asked Questions
Q: Can a lampholder certified to CSA C22.2 No. 39 be used directly in the US market?
A: Not without additional certification. While the standards are harmonized, US acceptance typically requires a UL 496 listing or a cULus mark. A CSA mark alone is strictly a certificate for the Canadian market.
A: Not without additional certification. While the standards are harmonized, US acceptance typically requires a UL 496 listing or a cULus mark. A CSA mark alone is strictly a certificate for the Canadian market.
Q: What distinguishes a standard lampholder from a “high-temperature” lampholder?
A: Standard medium-base lampholders are tested for a maximum cap temperature of 90 °C. High-temperature lampholders are designed for enclosed fixtures and are tested to higher ambient and operating temperatures, often reaching 150 °C or more on the cap.
A: Standard medium-base lampholders are tested for a maximum cap temperature of 90 °C. High-temperature lampholders are designed for enclosed fixtures and are tested to higher ambient and operating temperatures, often reaching 150 °C or more on the cap.
Q: Does the standard apply to lampholders used in portable lamps?
A: Yes. The lampholder itself must comply with C22.2 No. 39. Additionally, the complete portable luminaire must comply with the broader requirements of the CSA C22.2 No. 250 series.
A: Yes. The lampholder itself must comply with C22.2 No. 39. Additionally, the complete portable luminaire must comply with the broader requirements of the CSA C22.2 No. 250 series.
Q: How often must a CSA certified lampholder be re-evaluated?
A: Certification bodies conduct quarterly unannounced factory inspections to ensure the product continues to meet the standard. Major design changes require a full re-evaluation and type test.
A: Certification bodies conduct quarterly unannounced factory inspections to ensure the product continues to meet the standard. Major design changes require a full re-evaluation and type test.
As the lighting industry moves toward 2026 and beyond, the foundational requirements for screw-shell lampholders established in CSA C22.2 No. 39-13 (R2017) continue to provide a vital framework for safety, ensuring that these ubiquitous components perform reliably in millions of installations across Canada.