The method for measuring radon exhalation rate from the medium surface with a ventilation chamber is un-replaceable when surveying the radon exhalation rate continuously. Generally, the pump flow rate is an important parameter to obtain the radon exhalation rate from the measurement model. Our previous research indicated that the results of those measurements are inaccurate when the air change rate is not far larger than the effective decay constant. A no flow meter method is proposed for measuring radon exhalation from the medium surface with a ventilation chamber. A constant K is used to replace the sum of the air change rate and the effective decay constant. The radon exhalation rate and the value of K can be obtained by nonlinear data fitting through a novel model. The air flow rate is not a parameter of this model, and the flow meter is unnecessary in this measurement. The radon exhalation rates obtained by verification experiments are within the accepted values for the reference value. This method can be applied to develop and improve the instruments for measuring radon exhalation rate.

当连续测量the的呼出率时，用通风室从介质表面测量ra的呼出率的方法是不可替代的。通常，泵流速是从测量模型获得the呼出率的重要参数。我们以前的研究表明，当空气变化率不大于有效衰减常数时，这些测量结果是不准确的。提出了一种不带流量计的方法，用于通过通风室测量chamber从介质表面的呼出气。常数K用于代替空气变化率和有效衰减常数之和。through气呼出率和K值可以通过新型模型的非线性数据拟合获得。空气流量不是该模型的参数，并且在此测量中不需要流量计。通过验证实验获得的ra呼气率在参考值的可接受值范围内。该方法可用于开发和改进测量ra呼气率的仪器。