Driver's eye position relative to the 'H' point for trucks and buses

The eye position of subjects has been measured while they were driving the prototype of a bus intended for public service and in a static mock-up of this prototype. The average eye position observed in these tests was confirmed by photographing professional drivers while they drove an existing public service bus. With seat backs inclined at 10 degrees , the average eye position was found to be between 10 and 11 cms (4 and 4.5 in) in advance of the hip hinge point. The eye position found in this way agrees with an SAE recommendation but differs in its fore and aft dimension relative to the hip joint from that specified in some national and international regulations.