1. Probably a direct translation of the English expressions 'deaf and dumb' or ‘deaf mute’. These expressions are rather old-fashioned. They are considered offensive by some deaf people (because ‘dumb’ also means ‘stupid’ in English, not just ‘mute’) or misleading (because many deaf people can make themselves understood using their voices, i.e., they are not mute or dumb at all). Nonetheless, the sign itself is quite neutral and inoffensive.