Overview
EN ISO 8254-2:2016 - "Paper and board - Measurement of specular gloss - Part 2: 75° gloss with a parallel beam, DIN method" is a CEN-adopted international standard that defines a photometric method for assessing visual specular gloss of plane paper and board. The method measures a reflectometer value at a 75° angle using a parallel (collimated) beam - commonly known as the 75° DIN method. It applies to surfaces with gloss levels below 65 and is recommended as the preferred method for matt surfaces (gloss below 20). Materials containing optical brightening agents (OBAs) may be measured.
Key Topics and Technical Requirements
- Measurement geometry: 75° angle of incidence with a parallel (collimated) illumination beam; detection centered at the specular reflection angle.
- Reflectometer principle: The reflectometer value is proportional to the integrated reflection indicatrix within the instrument’s apertures and is scaled relative to a defined specularly reflecting surface (assigned value 100).
- Instrumentation components: collimator, decollimator, light source, photoelectronic receptor and sample holder (detailed description in Annex A).
- Calibration and standards:
- Use of zero-gloss and primary gloss standards for calibration (black glass plate or quartz wedge referenced in the standard).
- Working and intermediate gloss standards are used for routine checks; Annex B lists nominated organizations for calibration.
- Test conditions and preparation:
- Sampling guidance references ISO 186.
- Conditioning and atmosphere control follow ISO 187.
- Procedures for sample preparation, calibration, measurement, calculation and reporting are specified (see clauses on procedure and test report).
- Limitations: Precision data are not provided in this edition; the method is optimized for low-to-moderate gloss levels and is one geometry among ISO 8254 parts.
Applications
- Quality control and specification testing in:
- Paper and board production (coated and uncoated papers)
- Coating operations and converters assessing surface finish
- Independent testing laboratories and contract test services
- R&D teams developing surface treatments, coatings or optical additives
- Use cases include product classification (matt vs gloss), process control, incoming/outgoing inspections, and comparative evaluations where consistent geometry (75° DIN) is required.
Who Should Use This Standard
- Paper and board manufacturers, coating formulators, converters
- Quality assurance and metrology laboratories
- Standards bodies and procurement/specification engineers requiring reproducible gloss data for low-gloss surfaces
Related Standards
- ISO 8254-1 (75° converging beam, TAPPI method)
- ISO 8254-3 (20° gloss, TAPPI method)
- ISO 186 (sampling)
- ISO 187 (conditioning)
- CIE 038-1977 and EN 14086 (other gloss measurement guidance)
Keywords: EN ISO 8254-2:2016, specular gloss measurement, 75° gloss, reflectometer, DIN method, paper and board, parallel beam, optical brightening agents.