When you run a triggered SQL statement, it may cause the event of another, or even the same, trigger to occur, which in turn, causes the other, (or a second instance of the same) trigger to be activated. Therefore, activating a trigger can cascade the activation of one or more other triggers.
The run-time depth level of trigger cascading supported is 16. If a trigger at level 17 is activated, SQLCODE -724 (SQLSTATE 54038) will be returned and the triggering statement will be rolled back.