EN ISO 8308:2015 PDF

Overview

EN ISO 8308:2015 (ISO 8308:2015) - "Rubber and plastics hoses and tubing - Determination of transmission of liquids through hose and tubing walls" - specifies laboratory methods to measure how liquids are transmitted (by permeation and evaporation) through hose and tubing walls. The standard defines two test methods: Method A, a comparative, pressure-based test that simulates working conditions for all hose/tubing sizes; and Method B, a gravimetric, pressureless test for hose and tubing up to 16 mm inside diameter.

Key topics and requirements

• Two test methods
  • Method A: Uses a pressurised apparatus (nitrogen source, regulator, safety valve) where test pieces (e.g., a hose assembly with 250 mm free length or tubing samples) are charged with test liquid. Measurements are taken at 24 h intervals until a steady-state evaporation rate is reached. Test pressure: 50 kPa ± 5 kPa (gauge). Result expressed as steady-state evaporation in mL per m² per hour.
  • Method B: A pressureless reservoir is partly filled and attached to a length of hose/tubing (other end plugged). Assembly is weighed initially and daily for eight days. The result is the maximum mass loss in any 24 h period per unit inside surface area. The method accounts for permeation and evaporation and reduces selective permeation by daily agitation.
• Test pieces and sampling: Three test pieces required for Method A; defined internal free length and inside diameter measured per referenced standards.
• Test conditions: Standard test temperatures are (23 ± 2) °C or (27 ± 2) °C (ISO 23529). Test liquid is specified by the relevant product standard.
• Safety: Method A warns about hazardous vapours - tests must be performed in well-ventilated areas and apparatus must include safety provisions (safety valve, shield).
• Reporting: Test report must identify the hose/tubing, reference the standard, specify method used, test liquid, conditions and results.

Applications

• Assessing permeation and evaporation performance of rubber and plastic hoses and tubing used for fuels, solvents, hydraulic fluids, chemicals and other liquids.
• Comparative material and construction testing during product development and material selection.
• Quality control and type testing for manufacturers and test laboratories.
• Supplying objective permeability data for procurement specifications, regulatory compliance and safety assessments.

Who uses this standard

• Hose and tubing manufacturers
• Independent test laboratories and certified quality-control facilities
• R&D and materials engineers evaluating barrier performance
• Purchasing and compliance teams specifying hose performance
• Standards bodies and regulatory authorities

Related standards

• ISO 4671 - measurement of hose dimensions and lengths
• ISO 4788 - graduated measuring cylinders (laboratory glassware)
• ISO 23529 - specimen preparation and conditioning for rubber tests

Keywords: EN ISO 8308:2015, ISO 8308:2015, rubber and plastics hoses, tubing, transmission of liquids, permeation, evaporation, method A, method B, hose testing, permeability.