Tay Bridge disaster warned of their unreliability, and declined to estimate conditions at Dundee from readings taken elsewhere. One modern interpretation of available information suggests winds were gusting to . Usage of the bridge was restricted to one train at a time by a signalling block system using a baton as a token. At 7:13 p.m. a train from the south (consisting of a 4-4-0 locomotive, its tender, five passenger carriages, and a luggage van (brake van) slowed to pick up the baton from the signal cabin at the south end of the bridge, then headed out onto the bridge, picking up speed.
Tay Bridge disaster allowance for wind loading for spans less than , whilst noting this was for the design of girders not piers. Evidence was taken from scientists on the current state of knowledge on wind loading and from engineers on the allowance they made for it. Airy said that the advice given was specific to suspension bridges and the Forth; could act over an entire span of the Tay Bridge and he would now advise designing to (i.e. with the usual margin of safety). The highest pressure measured at Greenwich was ; it would probably go higher in Scotland. Sir George Stokes