This sign is on an exit door and judging by the fact that the man in it is running it would be fair to assume that it is important. An emergency exit of some sort. Lets say the buidling is on fire and you look at this sign. What's the white rectangle all about then? Lets have a heated debate about it. Then there's that arrow - if this was a raod sign it would point upwards to go forwards. There is no way you can go down so it must be pointing you back into the building. Which is handy. It's more handy if you happen to have a yellow helmet and a fire hos of course.
