FOI has been commissioned by the Swedish Fortifications Agency to perform a series of explosive tests with short and long term duration against various cable transits from the suppliers MCT-Brattberg, ROXTEC and RUTAB. The tests were carried out in FOI:s Shock Tube IV, located at Botele Udd Märsta, in November to December 2015. The transits were installed with different configurations of cabling and in some tests without cabling. Each cable transit was mounted with two modules, one on the pressure side and one on the back of the test object. Tightness control and possible leakage measurement of the intermediate volume was carried out before and after each test at each cable transit. The results of the measurements of the tightness control of the respective cable transit is presented in this report.