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Radiation Safety: Lead Shielding Guide

Purchase Lead Sheet(s) for Gamma Shielding:

Shielding reduces the intensity of radiation depending on the thickness. This is an exponential relationship with gradually diminishing effect as equal slices of shielding material are added. A quantity known as the halving-thicknesses is used to calculate this. The halving thickness of lead is 1 cm. Which means the intensity of gamma radiation will reduce by 50% by passing through 1 cm of lead.

For example;
1) A lead sheild 2.0 cm thick reduces gamma rays to 1/4 of their original intensity. (1/2 multiplied by itself two times)
2) 3.0 cm of lead reduces gamma radiation to 1/8 of their original intensity (1/2 multiplied by itself three times)

Halving thicknesses of some materials, that reduce gamma ray intensity by 50% (1/2) include:[5]
Material Halving Thickness[cm] Halving Thickness,[inches] Density,[g/cm³] Halving Mass,[g/cm²]
Lead 1.0 0.4 11.3 12
Steel 2.5 0.99 7.86 20
Concrete 6.1 2.4 3.33 20
Packed soil 9.1 3.6 1.99 18
Water 18 7.2 1.00 18

Column Halving Mass in the chart above indicates mass of material, required to cut radiation by 50%, in grams per square centimetre of protected area.

To get an idea of radiation dosage try using this Radiation Dose Chart.
(Courtesy of

Radiation Penetration Calculator

Radiation Safety