What is the term for the thickness of material that reduces the radiation to nine-tenths of its initial intensity?

The term that refers to the thickness of material that reduces radiation to nine-tenths of its initial intensity is known as the "tenth value layer." This concept is important in radiation physics and health physics as it helps quantify how much shielding material is necessary to attenuate radiation exposure.

The tenth value layer specifically indicates that after passing through this thickness of material, only 10% of the original radiation intensity remains, which is equivalent to a reduction to 90% of the initial intensity. It is a critical measurement for understanding the effectiveness of various materials used for radiation shielding.

In contrast, the half value layer refers to the thickness of material that reduces radiation to half of its initial intensity, which is a different measurement entirely. The quarter value layer is related but focuses on the reduction to one-fourth of the initial intensity. The term "reduction layer" is not a standard term in radiation physics. Understanding these varying terms is key in radiation safety and implementing appropriate protective measures.