What is ISO 3071 about?
ISO 3071 is on textile quality level provides the test methods on determining the pH value of aqueous extract in fibre for increasing the safety and quality level of the textile. The pH value in textile products determines the acid and alkali contents remaining in the fabrics. Plant fibres are best at neutral or slightly alkaline pH, and silk is best kept at a slightly acidic pH. Traces of strong acids on cotton fabric can affect the skin of the wearer.
ISO 3071 specifies a method for determining the pH of the aqueous extract of textiles. The method applies to textiles in any form (e.g., fibres, yarns, fabrics).
Who is ISO 3071 for?
ISO 3071 on the determination of pH of aqueous extract from textile is useful for:
- The textile industry
- Research and development personnel
- Quality control personnel
Why should you use ISO 3071?
pH is a measure of acidity or basicity of aqueous or other liquid solutions. The pH of processed textiles must be neutral and within the prescribed limits for a particular end use. Fabrics made from textiles of a higher pH value may exhibit challenges such as yellowing tendencies, change of shade upon storage and during shipment, poor dye pick up, patchy dyeing, and poor colourfastness. Very high and very low pH results in the degradation of textiles during storage and also poor softness and harsh feel. The pH of apparel fabrics that are in direct contact with the skin or used for babywear, must be controlled not to make the skin itchy.
ISO 3071 specifies the method to determine the pH of aqueous extract in textile. The aqueous extract is an extract prepared by evaporating a watery solution of the soluble principles of a vegetable drug (such as liquorice) to a semisolid or solid consistency.
ISO 3071 also includes the principle used, reagents and apparatus needed, preparation of test specimens, procedures, and calculation and expression of test results.
Since pH control is very important for your in-process quality as well as the quality of the finished material, ISO 3071 prescribes a method to determine this pH factor in your textile fibre.
What’s changed since the last update?
BS EN ISO 3071:2020 supersedes ISO 3071:2005. BS EN ISO 3071:2020 includes some editorial changes with reference to ISO 3071:2005. These include:
- In Preparation of test specimens only two test specimens are specified instead of three
- In Preparation of the aqueous extract water has been omitted as an extracting solution

