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D3781-02 – Standard Test Method Technical Guide
🔍 Scope and Terminology
ASTM D3781-02 specifies performance requirements for men’s and boys’ knitted rainwear and all-purpose water-repellent coat fabrics. It covers fabrics made from any textile fiber or mixture, but it is not applicable to interlinings. The standard defines “dimensional change” as change in fabric dimensions due to pressing and finishing during garment manufacture. It references ASTM D123 for general textile terminology and AATCC methods for testing. Requirements apply to both length and width directions where relevant.
📊 Specification Requirements
Fabrics must conform to the requirements in Table 1, which includes properties for water repellency, colorfastness, and dimensional stability. The following table lists the test methods referenced for evaluating these properties:
| 🟦 Property | 📐 Test Method | 🎯 Description |
|---|---|---|
| Water Repellency | AATCC 22-1974 | Spray Test |
| Water Resistance | AATCC 35-1974 | Rain Test |
| Colorfastness to Crocking | AATCC 8-1974 | Crockmeter Method |
| Colorfastness to Light | AATCC 16-1974 | Light Exposure |
| Colorfastness to Perspiration | AATCC 15-1976 | Perspiration Test |
| Colorfastness to Washing | AATCC 61-1975 | Accelerated Laundering |
| Dimensional Change | AATCC 96-1975 | Laundering Test |
Additionally, evaluation procedures like AATCC EP1 (Gray Scale for Color Change) and EP2 (Gray Scale for Staining) are used. Specific limits are detailed in Table 1 of the standard.
⚙️ Test Methods and Evaluation
Testing should follow the latest editions of cited methods. For colorfastness to burnt gas fumes, use AATCC 23. For non-chlorine and chlorine bleach exposure, AATCC 172 and AATCC 188 are specified. Water repellency and resistance are critical for rainwear, and dimensional change must be monitored to ensure fit after laundering. Note that industrial pressing and finishing treatments cannot be fully replicated in laboratory tests.
Important: The standard emphasizes that no laboratory method can fully replicate industrial pressing and finishing treatments. Therefore, allow for variations during garment production.
Tip: Always verify the latest edition of test methods as referenced in Section 7 of the standard to ensure compliance.
❓ Frequently Asked Questions
🔍 What fabric types are covered? This standard applies to men’s and boys’ knitted rainwear and all-purpose water-repellent coat fabrics, excluding interlinings.
💡 Why is water repellency testing important? Water repellency ensures the fabric repels water effectively, which is critical for rainwear performance. The spray test (AATCC 22) is commonly used.
⚡ How is dimensional stability assessed? Dimensional change is measured after laundering using AATCC 96 or AATCC 135 for durable press fabrics.
© 2026 TNLab — This article is a technical interpretation for reference only. The original standard as published by ASTM International takes precedence.