EN ISO 11665-7:2015

European foreword
Foreword
Introduction
1 Scope
2 Normative references
3 Terms, definitions and symbols
4 Principle of the measurement method
   for estimating surface exhalation rate
5 Equipment
6 Accumulation of radon in a container
7 Sampling
8 Detection method
9 Measurement
10 Expression of results
11 Test report
Annex A (informative) - Example of a sample results sheet
Annex B (informative) - Estimation of radon surface exhalation
        rate using a continuous measurement method
Annex C (informative) - Estimation of radon surface
        exhalation rate using a spot measurement method
Bibliography

ISO 11665-7:2012 gives guidelines for estimating the radon-222 surface exhalation rate over a short period (a few hours), at a given place, at the interface of the medium (soil, rock, laid building material, walls, etc.) and the atmosphere. This estimation is based on measuring the radon activity concentration emanating from the surface under investigation and accumulated in a container of a known volume for a known duration.This method is estimative only, as it is difficult to quantify the influence of many parameters in environmental conditions. ISO 11665-7:2012 is particularly applicable, however, in case of an investigation, a search for sources or a comparative study of exhalation rates at the same site. ISO 11665-7:2012 does not cover calibration conditions for the rate estimation devices.