⬜️🟦🟥🟨⬜️🟥 🟦⬛️🟨🟥⬛️🟨 🟥⬜️🟦⬜️🟨⬛️ ⬛️🟥🟨🟦🟥⬜️ The way in which objects or differences between surfaces are perceived is an important factor in the selection of materials and furnishings for a building or railway facility accessible to passengers - especially taking into account the needs of the visually impaired. Infracert TSI sp. z o.o. carries out contrast measurements both as part of on-site visits in the process of assessing compliance with TSI requirements as a Notified Body, as well as on individual customer orders. Colour contrast measurements are made by comparing the Light Reflective Value (LRV). This factor refers to the total amount of light reflected from a surface (e.g. floor, wall, stair tread finish, etc.) at each wavelength and in all directions when illuminated by a light source. The contrast of two adjacent surfaces is maintained by different values of the Light Reflective Value (LRV) or luminance. Spectrophotometry is a measurement technique that quantitatively measures the transmission or reflection of light through a sample. A spectrophotometer is equipped with a CLED lamp and a sample viewing camera is the primary tool used to investigate the requirements of LRV variation. The use of the spectrophotometer to measure the LRV provides an accurate assessment of the reflectance value. Critical issues in making in situ spectral measurements have been described in numerous scientific papers and include atmospheric properties, measurement time, measurement height, measurement orientation, field of view, spectral averaging and calibration of spectral data. They also define errors in field spectroscopy that need to be taken into account due to the potential impact on the accuracy of spectral measurements.