Persons on the road driving two wheelers or walking get injured or die when they were hit by the opening of doors of other vehicle users. This is because the person opening the door will not observe the traffic coming from behind or the persons walking. When the door hits, these persons may fall under other vehicles.
It is suggested to have sliding doors instead of outward opening doors for all vehicles so that the impact from such incidents can be reduced. Best is, to have doors on one side like in buses. But, this may not be practicable. Further, it depends on the road sense of other persons driving vehicles.