Physical Address
304 North Cardinal St.
Dorchester Center, MA 02124
CAN CGSB 4.2 No. 26.5-M89 (2013): Textile Test Methods — Colour Fastness to Washing
Understanding the Canadian Standard for Evaluating Colour Fastness in Textiles During Laundering
The CAN CGSB 4.2 No. 26.5-M89 (2013) standard is a key test method within the Canadian General Standards Board (CGSB) 4.2 series on textile test methods. Originally published in 1989 and reaffirmed in 2013, this standard provides a standardized procedure for determining the colour fastness of textiles to washing. It is widely referenced by textile manufacturers, quality assurance laboratories, and regulatory bodies in Canada and internationally for evaluating the resistance of dyed and printed fabrics to colour change and staining during laundering. This article examines the scope, technical requirements, implementation considerations, and compliance aspects of the standard.
Scope of CAN CGSB 4.2 No. 26.5-M89 (2013)
This standard specifies a test method for assessing the colour fastness of textiles to washing under controlled conditions. It is applicable to all types of textile materials, including natural, synthetic, and blended fibres, as well as finished and unfinished fabrics. The method simulates the effects of domestic or commercial laundering using specified detergent, temperature, mechanical action, and time. The test evaluates two primary aspects:
- Colour change: The alteration in shade, depth, or hue of the original test specimen.
- Staining: The transfer of colour from the test specimen to adjacent undyed textile materials (multifibre strip or single-fibre fabrics).
The standard sets out the apparatus, reagents, test conditions, and evaluation criteria necessary to obtain reproducible and comparable results. It is intended for use by textile testing laboratories, quality control personnel, and product development teams to ensure consistency in assessing wash fastness performance. The method aligns closely with international practices, notably ISO 105-C06, while maintaining specific Canadian requirements.
Tip: Although reaffirmed in 2013, users should verify if the latest edition of CAN CGSB 4.2 No. 26.5 is still applicable for their jurisdiction. Many laboratories consider this standard equivalent to ISO 105-C06 for practical purposes.
Technical Requirements and Test Procedure
The test method described in CAN CGSB 4.2 No. 26.5-M89 (2013) requires careful control of several variables to ensure reliable results. The following sections outline the key technical elements.
Test Specimen Preparation
The test specimen consists of a rectangular piece of the textile under evaluation, typically 100 mm × 40 mm. The specimen is placed in contact with a multifibre adjacent fabric (e.g., wool, acrylic, polyester, nylon, cotton, and diacetate) or up to two specified single-fibre adjacent fabrics. The assembly is stitched or stapled together to ensure intimate contact during laundering. For samples with printed or patterned areas, the test specimen should represent the overall colour effect.
Laundering Conditions
The washing process is conducted in a laboratory launder-O-meter or equivalent apparatus that provides controlled mechanical agitation, temperature, and time. The standard prescribes a series of test conditions (numbered from A to E) that simulate different laundering severities from mild to severe. The table below summarizes the typical conditions for the most common test (Condition A1).
| Parameter | Condition A1 (Mild) | Condition E (Severe) |
|---|---|---|
| Temperature | 40 ± 2 °C | 95 ± 2 °C |
| Liquor Volume | 150 mL per specimen | 150 mL per specimen |
| Detergent | ECE reference detergent (AATCC 1993 WOB or equivalent) | ECE reference detergent without optical brightener |
| Time | 30 minutes | 30 minutes |
| Steel Balls | None (A1) or 10 balls (A2) | 10 steel balls |
Additional conditions (B through D) offer intermediate temperatures (e.g., 50°C, 60°C, 70°C) and varying detergent or ball configurations. The selection of the appropriate condition depends on the intended end-use of the textile and the performance requirements.
Evaluation of Colour Change and Staining
After laundering, the test specimen is rinsed, dried, and conditioned. Colour change is assessed using a grey scale for colour change (e.g., ISO 105-A02 or equivalent). Staining on each adjacent fabric is rated using a grey scale for staining (ISO 105-A03). Ratings range from 1 (poor) to 5 (excellent). A minimum rating of 3–4 is often required for commercial acceptance, but this depends on the product specification.
Important: The standard does not specify pass/fail criteria. It provides the test method; acceptance limits should be agreed upon between the buyer and supplier or defined in a reference document (e.g., product standard).
Implementation in Quality Control
Successfully implementing CAN CGSB 4.2 No. 26.5-M89 (2013) requires trained personnel, calibrated equipment, and adherence to the precise protocol. Key considerations include:
- Apparatus: Ensure the launder-O-meter is calibrated for temperature and rotational speed (typically 40 ± 2 rpm). Steel balls must be of specified diameter (6 mm) and material (stainless steel).
- Detergent: Use fresh, non-contaminated detergent. The standard allows alternative detergents if correlation is demonstrated, but ECE reference detergent is recommended.
- Adjacent Fabrics: Multifibre strip should meet the specifications in ISO 105-F10 or equivalent. Single-fibre adjacent fabrics should be of known quality and free from finishing agents.
- Conditioning and environment: Specimens must be conditioned in a standard atmosphere (20 ± 2 °C, 65 ± 4% relative humidity) before assessment.
Good Practice: Many laboratories run a known reference material (e.g., a dyed cotton control) every test batch to verify the correct operation of the equipment and to monitor reproducibility over time.
The standard is often used in conjunction with other CGSB 4.2 test methods for a comprehensive evaluation of textile performance. For example, CAN CGSB 4.2 No. 26.3 covers colour fastness to light, and No. 26.6 deals with colour fastness to perspiration.
Compliance Notes
For manufacturers and importers aiming to sell textiles in Canada, compliance with CAN CGSB 4.2 No. 26.5-M89 (2013) may be required by retailers or by specific product regulations (e.g., bedding, apparel, uniforms). The standard is not a law itself, but it is commonly referenced in procurement contracts, product specifications, and as a basis for certification (e.g., CGSB compliance labels).
When declaring compliance, note the following:
- Reaffirmation: The 2013 reaffirmation confirms the technical content remains valid. However, users should check for any amendments that might have been issued.
- International equivalence: Many organizations accept results from ISO 105-C06 as equivalent, but some contracts explicitly require CAN CGSB 4.2 No. 26.5. Always confirm with the customer.
- Testing frequency: For ongoing quality control, it is advised to test each production lot if colour fastness is a critical performance attribute. Batch-to-batch variability can occur from dye chemistry or process changes.
Caution: Using a different edge-to-edge fabric composition (e.g., omitting certain fibres in the multifibre strip) may change the staining profile and invalidate comparison to specification limits. Always follow the standard’s exact requirements for adjacent fabrics.
Finally, any laboratory claiming accreditation for this test method should hold ISO/IEC 17025 accreditation from a recognized body (e.g., SCC in Canada). This ensures that the test results are technically valid and traceable.
Frequently Asked Questions
Q: What is the difference between CAN CGSB 4.2 No. 26.5-M89 (2013) and ISO 105-C06?
A: Both standards describe wash fastness tests using similar principles and test conditions. The main difference lies in the specific detergent formulations and the arrangement of test conditions. CAN CGSB 4.2 No. 26.5 is the Canadian adoption, while ISO 105-C06 is the international version. In practice, many laboratories use them interchangeably if the test condition codes are properly mapped, but contractual specifications should always be honoured.
A: Both standards describe wash fastness tests using similar principles and test conditions. The main difference lies in the specific detergent formulations and the arrangement of test conditions. CAN CGSB 4.2 No. 26.5 is the Canadian adoption, while ISO 105-C06 is the international version. In practice, many laboratories use them interchangeably if the test condition codes are properly mapped, but contractual specifications should always be honoured.
Q: How do I choose the right test condition (A, B, C, D, E) for my textile?
A: Select the condition that best simulates the intended laundering environment. Mild conditions (A1, A2) are suitable for delicate fabrics, while severe conditions (E) apply to cotton or polyester/cotton workwear that will be boiled or industrially washed. Reference to the product standard or customer specification will guide this selection.
A: Select the condition that best simulates the intended laundering environment. Mild conditions (A1, A2) are suitable for delicate fabrics, while severe conditions (E) apply to cotton or polyester/cotton workwear that will be boiled or industrially washed. Reference to the product standard or customer specification will guide this selection.
Q: Is this test method still current? Why was it reaffirmed in 2013?
A: Yes, it remains current. The 2013 reaffirmation means the standard’s technical committee reviewed the content and found no need for revision. However, users should monitor for any newer versions that may incorporate changes in detergent formulations or apparatus preferences.
A: Yes, it remains current. The 2013 reaffirmation means the standard’s technical committee reviewed the content and found no need for revision. However, users should monitor for any newer versions that may incorporate changes in detergent formulations or apparatus preferences.
Q: Can this standard be used for performance testing of home-laundry detergents?
A: Not directly. This method is designed to evaluate the textile’s colour fastness, not the detergent. For detergent performance tests, other standards (e.g., ASTM D4265 or ISO 4315) are more appropriate. However, the wash conditions defined in CAN CGSB 4.2 No. 26.5 can be adapted, but the standard strictly controls the detergent type.
A: Not directly. This method is designed to evaluate the textile’s colour fastness, not the detergent. For detergent performance tests, other standards (e.g., ASTM D4265 or ISO 4315) are more appropriate. However, the wash conditions defined in CAN CGSB 4.2 No. 26.5 can be adapted, but the standard strictly controls the detergent type.
Article compiled from open standard references and industry guidelines. Always refer to the official CAN CGSB 4.2 No. 26.5-M89 (2013) document for complete and authoritative requirements. — 2026