The effect of water can be seen as the result of its high hydrogen content. It is also noticed that as the concentration of boric acid solution increases, the attenuation increases. For the foam samples filled with 2% and 3% (w/v) boric acid in water, the 1.5 in. thickness samples totally stopped the beam, which is due to the high neutron absorption cross-section of boron-10 in the boric acid solution.