It seems to me that these two are pretty interchangeable for 'hallway' - at least in the writing I've read before.
My question is, though, is there any difference in meaning?
Any difference when to use one over the other?!
For buildings, according to 住宅设计规范(Design code for residential buildings) GB50096-2011,
So the internal transport space, such as the passageway inside the cinema or train, can be said as "过道".
And the transport space which is outside the building, independent, covered, can be said as "走廊".
Except for buildings, "走廊" can also be used for a narrow strip(corridor) connects two areas. Such as "河西走廊".
过道 means a passageway that could be either passed through by transportation such as cars or bikes, or by pedestrian. 过道 is more used in a open space.
走廊 is the word for "hallway." As the word 走（walk）suggests, it is usually used to mean a passageway in a build that could be walked through.
Note that 走道 also means passageway or aisle that could only be passed through by pedestrian as the word 走（walk）suggests.