What materials are commonly used for radiation shielding?

The use of specific materials for radiation shielding is fundamentally linked to their effectiveness in attenuating various types of radiation. Lead, water, and air are commonly employed due to their distinct properties.

Lead is renowned for its high density and atomic number, making it especially effective at blocking gamma rays and x-rays. Its capability to absorb and scatter these forms of radiation is why it is a preferred choice in medical and industrial applications.

Water serves as both a neutron and gamma radiation shield; it is beneficial because of its abundance and the ability of hydrogen atoms in water to slow down neutrons effectively. Additionally, large bodies of water are often used in nuclear reactors for shielding, serving as both a coolant and a radiation barrier.

Air, while less effective than lead or water, does provide some degree of shielding for low-energy particles and is often considered in the context of attenuation of radiation in open environments or for dose assessments at varying distances.

In contrast, while concrete is also a viable radiation shielding material due to its density and ability to slow down neutrons, the inclusion of wood, plastic, iron, aluminum, and glass, in other choices, does not match the effectiveness of lead, water, and air for strong radiation shielding roles.