In measuring the sound transmission loss of glass panes, there are many important factors such as the size of specimen, the test opening and installing conditions. Therefore, many researches were performed in order to examine the influence of the factors. In order to measure the test specimen in the standardized conditions, additional test requirements for installation of glass panes is included in ISO standard 140-1 and 3 (ISO method). However, it differs from the conventional Flat Glass Association method (FGA method), in which the sound transmission loss has been measured by following the actual Japanese window installation. Therefore, it is important to make clear the difference between the two methods, because we have already accumulated performance data of many kinds of glass panes and also clarified the influence of the niche (niche effects) by applying FGA method.
