EN ISO 105-A08:2002 PDF

Overview

EN ISO 105-A08:2002 (ISO 105-A08:2001) is a vocabulary standard adopted by CEN that defines the terms and definitions used for colour measurement in the ISO 105 series on textiles - tests for colour fastness. Its scope is limited to providing consistent, authoritative terminology for use throughout ISO 105; the definitions are intended to be applied only within that context.

Keywords: EN ISO 105-A08, ISO 105-A08, colour measurement vocabulary, textiles colour fastness, CIELAB, ΔE, spectrophotometer.

Key topics

This part compiles standardized definitions and notes for colour-metric and photometric concepts commonly used in textile fastness testing, including:

• Colour attributes: lightness (L*), hue, chroma and whiteness.
• Colour spaces and differences: CIE 1976 Lab (CIELAB)* and CIELAB colour difference (ΔE*ab).
• CIE concepts: standard observer data, standard illuminants (A, C, D65 and F-series), chromaticity coordinates and tristimulus values (X, Y, Z).
• Measurement instruments: spectrophotometer, colorimeter, and the role of a perfect reflecting diffuser for calibration.
• Spectral properties: spectral power distribution (SPD), spectral reflectance and transmittance, and the spectral ranges for visible, ultraviolet (UV) and infrared (IR) radiation.
• Practical textile terms: colourant, fluorescent whitening agent (FWA), tinctorial strength, standard depth scale, grey scale (for change and staining), photochromism.
• Colour-difference evaluation: single-number evaluation (ΔE), and references to other metrics (e.g., CMC) and CMC ellipsoid semi-axes used in ΔE calculations.

Applications

EN ISO 105-A08:2002 provides the standardized language needed to:

• Ensure consistent interpretation of colour measurement results across ISO 105 test methods.
• Support test laboratories in reporting and comparing colour fastness and colour difference (ΔE) outcomes.
• Guide manufacturers, dye houses, and quality assurance teams when specifying colour tolerances and interpreting instrument output (spectrophotometers, colorimeters).
• Help instrument and software vendors align nomenclature (CIELAB, chromaticity, SPD, illuminants) with industry practice.

Who should use this standard

• Textile and apparel manufacturers
• Colour technologists and textile chemists
• Accredited test laboratories and QA departments
• Spectrophotometer and colorimetry instrument developers
• Standards committees and technical writers working on ISO 105 series

Related standards

• ISO 105-A01 - General principles of testing
• ISO 105-A02 - Grey scale for assessing change in colour
• ISO 105-A03 - Grey scale for assessing staining

Using EN ISO 105-A08 helps eliminate ambiguity in colour measurement terminology, improving communication and reproducibility in textile colour fastness testing.