This standard describes the specific `Design for PRM Use' requirements applying to both infrastructure and rolling stock on the trans-European network (TEN) and the assessment of those requirements. The following applies to this standard. The definitions and requirements describe specific aspects of `Design for PRM Use' required by people with reduced mobility as defined in TSI PRM. This standard defines elements which are universally valid for obstacle free travelling including lighting, contrast, tactile feedback, transmission of visual and acoustic information. The definitions and requirements of this standard are to be used for rolling stock applications. This part of the standard covers those requirements relating to "Contrast". The standard only refers to aspects of accessibility for PRM passengers it does not define non PRM related requirements and definitions for specific components and systems. This standard assumes that the infrastructure or vehicle are in the defined operating condition, any damages or operating failures shall not be taken into account when assessing these requirements. Where minimum or maximum dimensions are quoted these are absolute NOT nominal requirements. The following areas of `General Requirements' are covered in 3 parts: Part 1 contains contrast; Part 2 contains spoken information; written information; tactile information; pictograms; Part 3 contains lighting; anti-reflection properties; transparent obstacles; slip resistance. This standard describes these areas with clear and consistent terms and definitions. Measurement methods and/or assessment procedures needed to establish a clear pass/fail assessment are provided where necessary.