Overview
EN ISO 8130-2:2021 specifies the referee method for the determination of density of all types of coating powders using a gas comparison pycnometer. Prepared by ISO/TC 35 in collaboration with CEN/TC 139, this second edition aligns the procedure with current practice and replaces the 1992 edition. The standard is used where precise, repeatable density data are required for quality control, product specification and formulation development.
Key Topics
- Scope: Density determination for all coating powder types by gas comparison pycnometry.
- Principle: Density is calculated from the mass and the gas-displaced volume of a weighed test portion. Volume is obtained by measuring the pressure difference when the sample is introduced into the pycnometer.
- Gases: Helium or nitrogen (minimum Grade 4.8) are specified; other high-purity gases may be used if they do not affect the product and the deviation is recorded.
- Apparatus: Ordinary laboratory equipment plus a gas comparison pycnometer (manual or automated). The instrument uses equal-dimension sample and reference chambers and a pressure-difference meter.
- Sampling and conditioning: Take representative samples per ISO 15528. Perform determinations at (23 ± 1) °C and, where applicable, (50 ± 5) % RH.
- Measurement precision and limits:
- Mass measured to the nearest 1 mg.
- Measured pressure difference shall not exceed 1 %.
- For manual pycnometers, swept volumes should match within 0.5 %.
- Two volume measurements are taken and their mean used; if duplicate density results differ by more than 2 %, the test is repeated.
- Reporting: Include product identification, reference to ISO 8130-2:2021, pycnometer type, gas grade, test result (to 0.01 g/cm³), any deviations, anomalies and test date.
Applications
- Quality control and acceptance testing of coating powders.
- Raw material and finished product specification for powder coatings manufacturers.
- Formulation and density-related calculations used in process control, layer thickness estimation and material cost analysis.
- Comparative or referee testing where a standardized, traceable density value is required.
Automation of gas pycnometers is encouraged to reduce operator error; manual pycnometers remain acceptable with appropriate care. Note that the choice of gas can influence results through sample drying - record the gas used in the test report.
Related Standards
- ISO 8130-14 - Vocabulary for coating powders (terms and definitions referenced in Clause 3).
- ISO 15528 - Sampling for paints, varnishes and raw materials (sampling requirements cited).
- ISO 12154 - Gas pycnometry methods for skeleton density (listed in bibliography).
This concise guide highlights the practical value of EN ISO 8130-2:2021 for laboratories and manufacturers that need reliable, repeatable density measurements of coating powders using gas comparison pycnometry.