What must be done before a train can proceed over a grade crossing?

Before a train can proceed over a grade crossing, it is essential to make sure that the gates are in a horizontal position. This indicates that the crossing is clear and that it is safe for the train to continue. When crossing gates are horizontal, they signal to both pedestrians and vehicular traffic that it is safe to pass.

Ensuring the safety of the grade crossing is a critical aspect of rail operations. Grade crossings are potential points of conflict between trains and other road users, so proper procedures must be followed to minimize the risk of accidents. The position of the gates is a direct indication of whether the crossing is controlled and safe for the train to traverse.

While the other options may involve checks and procedures relevant to train operation, they do not directly address the specific requirement for grade crossings. Hence, confirming the horizontal position of the gates is the critical action that must be taken before a train can safely continue through a grade crossing.