Abstract
Observations were made of 57 drivers who approached a rural railgrade crossing in the presence of activated warning flashers signalling an approaching train. Two thirds of the drivers crossed the tracks in front of the approaching trains. All but four drivers, however, slowed perceptibly or stopped prior to crossing. The probability of crossing was seen to vary reliably with distance of the trains from the crossing and the time available to cross (safety margin). It was concluded that, as a group, the drivers' decision to cross was a considered one that was based on an accurate perception of available evidence. (a).