ISO 11665-7:2012给出了在给定地点、介质（土壤、岩石、铺设的建筑材料、墙壁等）和大气界面的短时间（几个小时）内估算氡-222表面呼出率的指南。该估算基于测量被调查表面散发的氡活动浓度，并在已知时间内累积在已知体积的容器中。 由于难以量化环境条件中许多参数的影响，该方法仅为估计方法。 ISO 11665-7:2012特别适用于同一地点的调查、源搜索或呼气率对比研究。ISO 11665-7:2012不包括速率估计装置的校准条件。

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.