Baggage scanner colour codes are specifically related to the images of the targets visible on the monitor. The scanned targets appear as colour pallets on the monitor and each colour have significance. The tone of the colour decides the material and possible threats.The X rays see exactly what is in luggage but that is coded in colours visible on the monitor to the operator. In general the airport X-ray scanners produce images in orange, blue and green. Each colour corresponds to a material category viz.a.viz