Asked by: Raguel Subhangi
science physics

What is the half thickness of lead?

Last Updated: 3rd June, 2020

4.2 mm

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Keeping this in consideration, what is the HVL of lead?


Material HVL (mm)
30 keV 60 keV
Tissue 20.0 35.0
Aluminum 2.3 9.3
Lead 0.02 0.13

One may also ask, what is half thickness method? A material's half-value layer (HVL), or half-value thickness, is the thickness of the material at which the intensity of radiation entering it is reduced by one half. The quarter-value layer is equal to the sum of the first and second half-value layers.

Thereof, how do you calculate half thickness?

The half-value layer formula is HVL = = 0.693/μ. Multiply your answer by 10 to express your HVL in millimeters. This is necessary because many attenuation coefficients are given with the units cm-1, and some HVLs are expressed in mm. Your answer can also be multiplied by 0.39 to convert centimeters to inches.

How thick must lead be to block radiation?

shield need to be about 13.8 feet of water, about 6.6 feet of concrete, or about 1.3 feet of lead. Thick, dense shielding is necessary to protect against gamma rays. The higher the energy of the gamma ray, the thicker the shield must be. X-rays pose a similar challenge.

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