Abstract
Recently, wooden houses in Hokkaido have become more airtight. As concern for indoor air quality has grown, so too has the need to measure interzonal airflows in houses to assess the distribution of outdoor air. Interzonal airflows betseen rooms are usually calculated by measuring concentrations of tracer gases in each room. Therefore, gas injection methods as well as analytical methods must be discussed for calculating appropriate interzonal airflows. 1) Interzonal airflows by the decay mode should be calculated during suitable times, not just after injection and or at the end of the decay. 2) Interzonal airflows by the constant injection mode can be calculated as fairly stable rates. If it is adopted over a long period of time, interzonal airflow can be calculated as a variable of elapsed time, and it can reduce the causes of errors such as a rounded effect. 3) The integral method under a steady condition can be used to calculate the stable and appropriate interzonal airflow rates over a long period of time. On the other hand, the differential method, during a suitable time, can be used to calculate more accurate interzonal airflow rates than is possible by the integral method. 4) The constant injection mode over a long period of time should be chosen as the tracer gas injection method for field measurements. Either the integral method or the least squares method by governing differential representation should be adopted as the appropriate analytical method in such a case.
