MTR
Bylaws have been recently introduced to deter potentially dangerous actions on the MTR, such as the ban of flammable goods on the MTR and rushing into trains when the doors are closing. Penalties ranging from fines to imprisonment have been imposed for such offenses. Metallic balloons are also banned due to previous incidents on KCR and on MTR's Island Line where a metallic balloon interfered with the operation of the overhead power lines.