A system for scanning a person before access to a restricted access area, the system comprising: a surface (19, 19') onto which a person can walk; a metal detector (10, 70) configured to detect a metal object in 5 the shoes worn by the person and/or a metal object located in a waist portion of the person when the person walks on said surface; a position identifying mark (11, 71) indicating a specific position on said surface with respect to the metal detector (10, 70); an indication unit (12, 13) for providing instructions to the person 10, directly or through an assistant; and a processing unit controlling the indication unit (12, 13) for: a) performing a first scan of the shoes worn by the person when the person walks on said surface; b) prompting or allowing the person to walk towards the restricted area if the first scan of the person's shoes and/or a waist portion of the person performed by the metal detector indicates a probability of a 15 presence of metal lower than a first threshold; c) prompting the person to place his feet and/or himself close to said position identifying mark if the first scan of a person's shoes indicates a probability of a presence of metal higher than the first threshold, in order to carry out, by means of the same metal detector, a 20 second scan of said shoes and/or of said waist portion at the specific position with respect to the metal detector, or d) prompting or allowing the person to remove his shoes and/or remove objects from his waist portion if the first scan indicates a probability of a presence of metal higher than a second threshold, or if the second scan indicates a probability of a presence of metal in the shoes 25 and/or in said waist region higher than a third threshold. a surface (19, 19') onto which a person can walk; a metal detector (10, 70) configured to detect a metal object in 5 the shoes worn by the person and/or a metal object located in a waist portion of the person when the person walks on said surface; a position identifying mark (11, 71) indicating a specific position on said surface with respect to the metal detector (10, 70); an indication unit (12, 13) for providing instructions to the person 10, directly or through an assistant; and a processing unit controlling the indication unit (12, 13) for: a) performing a first scan of the shoes worn by the person when the person walks on said surface; b) prompting or allowing the person to walk towards the restricted area if the first scan of the person's shoes and/or a waist portion of the person performed by the metal detector indicates a probability of a 15 presence of metal lower than a first threshold; c) prompting the person to place his feet and/or himself close to said position identifying mark if the first scan of a person's shoes indicates a probability of a presence of metal higher than the first threshold, in order to carry out, by means of the same metal detector, a 20 second scan of said shoes and/or of said waist portion at the specific position with respect to the metal detector, or d) prompting or allowing the person to remove his shoes and/or remove objects from his waist portion if the first scan indicates a probability of a presence of metal higher than a second threshold, or if the second scan indicates a probability of a presence of metal in the shoes 25 and/or in said waist region higher than a third threshold. a) performing a first scan of the shoes worn by the person when the person walks on said surface; b) prompting or allowing the person to walk towards the restricted area if the first scan of the person's shoes and/or a waist portion of the person performed by the metal detector indicates a probability of a 15 presence of metal lower than a first threshold; c) prompting the person to place his feet and/or himself close to said position identifying mark if the first scan of a person's shoes indicates a probability of a presence of metal higher than the first threshold, in order to carry out, by means of the same metal detector, a 20 second scan of said shoes and/or of said waist portion at the specific position with respect to the metal detector, or d) prompting or allowing the person to remove his shoes and/or remove objects from his waist portion if the first scan indicates a probability of a presence of metal higher than a second threshold, or if the second scan indicates a probability of a presence of metal in the shoes 25 and/or in said waist region higher than a third threshold.