As a rule, the safety assessment of road bridges to braking events combines the braking force, acting along the longitudinal axis of the deck, with a vertical load that accounts for the vertical component of the traffic action. While in modern design standards the calibration procedure of the vertical load models followed a probabilistic evaluation targeting a predefined reference return period, the braking force was derived from a basic characterization of the braking process and with simplified vehicle configurations. As a consequence, the return period of the braking force is unclear and may not be consistent with that of the vertical load model. Without a measure of the return period, the braking force may be too conservative if it has a much higher return period than the other traffic loads, and hence its enforcement might lead to an uneconomical design or an uncalledfor retrofitting intervention. On the other hand, safety verifications with a braking force with a smaller than pre-established return period conceal increased risks of structural damage, namely at the level of the bridge elements responsible for accommodating horizontal displacements of the bridge deck and/or carrying the horizontal loads to the ground, such as expansion joints, bearings, piers and abutments.