Yes, for tall people it would be: "De man is lang", for tall objects it would be: "De brug is hoog" or "Het huis is hoog". If you want to emphasize the length of the bridge, rather then the height, you would say: "De brug is lang".
What about "The bridge is tall"?
That would be: "De brug is hoog".
So you would only use lang to mean Tall when describing people, would that be right?