ISO 1833-1:2020

Overview

ISO 1833-1:2020 - Textiles - Quantitative chemical analysis - Part 1: General principles of testing - defines the common principles used to determine the fibre composition of textile mixtures. It covers the general method of removing non‑fibrous matter, identifying components, and measuring proportions by selective dissolution or manual separation. Results are reported on a dry‑mass basis and used in conjunction with the specific procedures given in other parts of the ISO 1833 series.

Key topics and technical requirements

• Scope and principle: Common method for quantitative chemical analysis of fibre mixtures; the insoluble residue is weighed after removal of soluble components to calculate composition.
• Pre‑treatment: Removal of non‑fibrous matter (oils, waxes, sizes, water‑soluble matter) is required before analysis (Annex A normative).
• Preferred methods: Manual separation (Annex B normative) is recommended when practicable because it often gives more accurate results than chemical dissolution.
• Reagents and safety: Use analytical‑grade reagents; grade 3 water per ISO 3696 is specified. The standard warns about health and environmental hazards from certain reagents.
• Apparatus and conditions: Examples include glass filter crucibles (90–150 μm sintered disk), ventilated oven at (105 ± 3) °C for drying, analytical balance with 0.0002 g resolution, Soxhlet extractor. Ordinary room conditions are acceptable for analysis.
• Procedures and reporting: Instructions for sampling, handling, drying, weighing, calculation of results, precision, and mandatory items in the test report. At least two determinations on separate specimens are required.
• Corrections and limitations: Correction factors are provided where reagents partially affect insoluble fibres; dyes are generally regarded as part of the fibre and not removed. Some added resins or finishes that cannot be removed invalidate the method.

Applications

• Quality control and compliance: Verify fibre content for labeling, product specifications and regulatory compliance.
• Laboratory testing: Routine analytical labs use ISO 1833-1 as the foundational procedure before applying part‑specific methods.
• Supply chain verification: Confirm supplier claims on blended yarns, fabrics and finished goods.
• Forensic and research: Textile composition analysis in investigations and materials research.

Who uses it?

• Textile testing laboratories, manufacturers, quality managers, regulatory bodies, customs authorities and research institutions.

Related standards

• ISO 1833 series (part‑specific methods)
• ISO 5089 (sample preparation)
• ISO 3696 (water for laboratory use)
• ISO 2076 and ISO 6938 (generic fibre names)
• ISO/TR 11827 (fibre identification)
• ISO 105‑C10 (related test methods)

Keywords: ISO 1833-1:2020, textiles, quantitative chemical analysis, fibre mixtures, selective dissolution, manual separation, pre‑treatment, dry mass, textile testing.