常用建材的放射性 （pCi/g)

材料                            Uranium                      Thorium                       Potassium

 

Granite                        1.7                               0.22                             32

Sandstone                   0.2                               0.19                             11

Cement                        1.2                               0.57                             6.4

Limestone Concrete    0.8                               0.23                             2.4

Sandstone Concrete    0.3                               0.23                             10

Drywall                       0.4                               0.32                             2.4

Natural Gypsum          0.4                               0.2                               4

Wood                          -                                   -                                   90

Clay Brick                   3                                  1.2                               18