Comparison of Flame Retardant Standards for Electric Wires and Cables
Time: 2025-03-17 14:28:54
Source: Henan Province Jianyun Cable Co., Ltd.
Introduction
With the increasing demand for fire safety in electric wires and cables, flame retardant standards play a critical role in preventing fire hazards and the spread of flames. This paper compares the domestic and international flame retardant standard systems, focusing on GB/T 19666-2019 and GB 31247-2014, and analyzes the key technical indicators, sample burning methods, and combustion test parameters.
1. Current Standards for Flame Retardant Cables
1.1 International Standards (IEC 60332 Series)
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IEC 60332-1-1:2015, IEC 60332-1-2:2004, and IEC 60332-1-3:2004 focus on the flame spread height based on non-metal content in cables.
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China adopts these standards through GB/T 18380-2022, which aligns with IEC 60332.
1.2 Chinese National Standards
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GB/T 19666-2019: General rules for flame-retardant and fire-resistant electric wires and optical cables.
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GB 31247-2014: Classification for burning behavior of electric and optical cables.
2. Key Technical Indicators Comparison
2.1 Assessment Items
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Standard
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Assessment Items
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GB/T 19666-2019
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Carbonization height ≤ 2.5 m
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GB 31247-2014
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Heat release, smoke generation, flame spread, and burning growth rate
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2.2 Sample Burning Quantity
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Flame Retardant Level
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Non-Metal Volume Fraction
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Minimum Number of Samples
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AF/R Class
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7.0
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4
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A Class
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7.0
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2
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B Class
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3.5
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2
|
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C Class
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1.5
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2
|
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D Class
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0.5
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2
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2.3 Binding Method for Sample Bundles
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Standard
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Binding Method
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GB/T 19666-2019
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Based on conductor cross-section area and cable diameter
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GB 31247-2014
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Determined solely by cable diameter
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2.4 Combustion Test Time
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Standard
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Combustion Time
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GB/T 19666-2019
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40 min for AF/R, A, B Classes; 20 min for C and D Classes
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GB 31247-2014
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20 min for all levels
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3. Challenges in Standard Implementation
3.1 Airflow Control During Combustion
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Air intake flow rate and airflow direction significantly impact test accuracy.
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Maintaining 8000 L/min airflow stability is essential for consistent results.
3.2 Burner Position and Stability
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Positioning the burner at a 75 mm distance from the sample affects heat release rate.
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Clogged nozzles due to residue buildup can lead to inaccurate readings.
3.3 Environmental Temperature Control
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Standard requires 5°C to 40°C ambient temperature with 16 hours of pre-treatment at (20±10)°C.
4. Conclusion and Recommendations
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GB/T 19666-2019 focuses on preventing flame spread, while GB 31247-2014 emphasizes heat release and smoke production.
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For high-rise buildings and subways, GB 31247-2014 provides better fire safety protection.
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Cable manufacturers should customize cable structure and materials to meet different flame retardant standards.
5. Keywords
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Flame Retardant Cable Standards
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Fire Performance of Electric Cables
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Heat Release and Smoke Control
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IEC 60332 and GB Standards
6. References
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Zhao Di (2024). Comparison on Flame Retardant Standards of Electric Wires and Cables. Wire & Cable, No.6, 2024. DOI: 10.16105/j.dxdl.1672-6901.202406009
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GB/T 19666-2019 - General Rules for Flame Retardant Cables
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GB 31247-2014 - Classification for Burning Behavior of Cables
