Overview
ISO/TS 11665-13:2017 provides a standardized laboratory method for determining the radon diffusion coefficient in waterproofing materials (membranes, coatings, paints). Known as the membrane two‑side activity concentration test method, it defines test principles, measuring‑system configuration, sample preparation, boundary conditions and the expression of results. The technical specification is intended for non‑porous, monolayer or multilayer waterproof materials; it is explicitly not applicable to porous materials where porosity and moisture dominate radon transport.
Key topics and technical requirements
- Purpose: Quantify the radon diffusion coefficient (D) and related parameters (equivalent diffusion coefficient, diffusion length, diffusive exhalation rate) to assess barrier performance against radon-222.
- Test principle: Measure radon activity concentrations on both sides of a membrane sample and apply analytical/numerical methods to derive D.
- Methods described:
- Method A - non‑stationary (transient) radon diffusion analysis;
- Method B - stationary radon diffusion during steady‑state conditions;
- Method C - stationary conditions established with ventilation of the receiver container.
- Measuring system: Components and configuration requirements for source and receiver chambers, detectors, sealing and radon‑tight mounting of samples.
- Sample handling: Preparation, fixing of samples in the test device and rules for multilayer materials to determine an equivalent diffusion coefficient.
- Quality & metrology: Procedures for radon‑tightness testing, assessment of leakage, estimation of uncertainty, decision thresholds and detection limits (per ISO 11929 and GUM principles).
- Reporting: Required test report content, influence quantities, and calibration/quality‑management expectations for test laboratories.
Practical applications
- Assessing performance of radon‑proof insulation used in foundations and building envelopes.
- Providing input values for building codes and regulations that set maximum allowable radon diffusion coefficients for waterproof membranes.
- Certification and quality control for manufacturers of bitumen and polymeric membranes, coatings and paints intended to reduce indoor radon.
- Supporting radon mitigation design by radon‑mitigation contractors, building physicists and environmental health professionals who require validated diffusion coefficients for modeling indoor radon transport.
Who uses this standard
- Accredited testing and calibration laboratories
- Material manufacturers and R&D teams
- Building code authorities and regulators
- Radon mitigation specialists, indoor air quality consultants and architects
Related standards
- ISO 11665‑1, ‑5, ‑6 (radon origins and activity concentration measurement methods)
- ISO/TS 11665‑12 (related methods for material testing)
- ISO 11929 (detection limits for ionizing radiation)
- ISO 80000‑10 and ISO/IEC Guide 98‑3 (units and uncertainty of measurement)
Keywords: ISO/TS 11665-13, radon diffusion coefficient, radon measurement, waterproofing materials, membrane test method, radon‑proof insulation, diffusion length, radon exhalation.