Signs for the blind are commonly used in Europe and in the world as a safeguard, e.g. of platforms on railway stations and tube stations, and in public use buildings. In our country, signs for the blind have just begun appearing in some buildings. Warning surfaces are a type of horizontal signs installed on the edge of the platform without the need of removing of the current surface. They have a form of bumps equally distributed on a given surface which make it easily recognisable under the feet. The guiding strips enable easy arrival at a suitable platform or sector by outlining the passageways.