Do a search on the web for the International Symbol of Accessibility and I'm sure you can find some. So all your entrances are not accessible? You would need directional signs at all the other entrances if that case. If you do not have unaccessible entrances - you don't need a sign. Is your new accounts desk specifically designed for accessibility? If so, I'm not aware that you specifically need to put a sign on it. There is no requirement for a sign in 7.1 of the accessibility guidelines.
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