Preliminary testing of innovative ventilation fittings Bogdan Derbiszewski, Michał Głogowski, Łukasz Szymański, Tomasz Olejnik and Andrzej Obraniak E3S Web Conf., 44 (2018) 00029 Published online: 03 July 2018 DOI: 10.1051/e3sconf/20184400029