In shielding calculations, what does HVL stand for and what does it describe?

In shielding calculations, what does HVL stand for and what does it describe?

• A. Horizontal Value Layer; shielding along the beam path.
• B. Half-Value Layer; the thickness required to reduce the radiation intensity by half.
• C. High-Volume Layer; shielding beyond 1 HVL.
• D. Heavy Value Layer; the thickness to stop all radiation.

Answer: (B)