BS ISO 7249:2024
Textiles. Fibres. Determination of burning behaviour by oxygen index
- Standard No.
- BS ISO 7249:2024
- Release Date
- 2024
- Published By
- British Standards Institution (BSI) GB / BSI
- Latest
- BS ISO 7249:2024
- Introduction
Analysis of the core content of the standard
This standard uses an oxygen index tester to measure the combustion characteristics of textile fibers in a vertical state, and evaluates the flame retardant properties of materials by quantifying the minimum oxygen concentration (OI value) required to maintain combustion. The test environment must strictly control the gas flow rate (40±2 mm/s) and the temperature and humidity range (10-30°C, 30-70%RH).
Comparison of key test parameters
Fiber type Sample mass (g) Twist (turns) Pretreatment requirements Short fiber 0.30±0.03 110-150 Need to be opened and combed Filament yarn 0.30±0.03 60-80 Generally no need to clean
Technology evolution analysis
Compared with the previous version of the standard, the 2024 version has the following major updates:
- It is clearly stated that a dual system of mass flow controller and oxygen analyzer should be used to verify gas concentration
- Added suggestions for singeing treatment of surface hairiness of staple fibers
- Refine the allowable range of test environment fluctuations (temperature ±2°C)
Implementation suggestions
Case: The test of a flame-retardant polyphenylene sulfide staple fiber showed that the burning length exceeded 50mm when the oxygen concentration reached 33.6% (Appendix B data). Recommended for enterprises:
- Regularly calibrate the gas mixing device to ensure that the concentration deviation is ≤0.5%
- Prepare at least 15 samples for each test to ensure statistical validity
- Pay attention to record secondary combustion characteristics such as molten droplets and smoke
Safety Warning
The standard specifically emphasizes that the test process may involve the operation of hazardous materials, requiring laboratories to be equipped with exhaust exhaust systems and operators to receive professional training. The test results only reflect the combustion performance under specific conditions and cannot directly infer the actual fire risk.
BS ISO 7249:2024 Referenced Document
- ISO 139 Textiles — Standard atmospheres for conditioning and testing AMENDMENT 1
- ISO 2060 Textiles - Yarn from packages - Determination of linear density (mass per unit length) by the skein method
- ISO 2061 Textiles - Determination of twist in yarns - Direct counting method
- ISO 4589-1 Plastics - Determination of burning behaviour by oxygen index - Part 1: General requirements
- ISO 4589-2:2017 Plastics - Determination of burning behaviour by oxygen index - Part 2: Ambient-temperature test
- ISO 4880 Burning behaviour of textiles and textile products - Vocabulary
- ISO 6741-3:1987 Textiles; Fibres and yarns; Determination of commercial mass of consignments; Part 3 : Specimen cleaning procedures
BS ISO 7249:2024 history
- 2024 BS ISO 7249:2024 Textiles. Fibres. Determination of burning behaviour by oxygen index
