Valavu yachitetezo ndi chida chachitetezo chomwe chimangotseguka kuti chiwongolere kupanikizika pamene kupanikizika mkati mwa tanki yosungiramo gasi yamafuta kumawonjezeka. Matanki osungiramo gasi amafuta amafuta ayenera kugwiritsa ntchito ma valve otetezedwa otetezedwa ndi masika.
