Buildings as Shielding The numbers in the diagram represent a radiation dose reduction factor. For example, the number 50 indicates that a person in that area would receive l/50th of the dose of a person standing outside of the building. Higher numbers indicate more protection from ionizing radiation. Office/Large Apartment Building 1-story Brick Brick, vendor concrete Wood frame Brick, concrete ¦ M ¦ 9-1' | »-» 100-199 g >200 Source: https://www.ready.gov/ ------- |