Radiation Shielding Attenuation
Compute the radiation intensity after passing through shielding, I = I₀·e^(−μ·x), by the exponential attenuation law, from the initial intensity (I₀), the material's linear attenuation coefficient (μ) and the thickness (x). Unlike alpha and beta particles (which have a finite range), gamma rays and X-rays are only exponentially attenuated — never fully blocked. It is the basis of shielding calculation. Enter the initial intensity, the attenuation coefficient and the thickness.
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Atenuação de radiação (blindagem)
A radiação gama e os raios X têm uma característica que os distingue das partículas alfa e beta: eles não têm um 'alcance' definido onde param de repente. Em vez disso, são atenuados exponencialmente — cada camada de material remove uma fração fixa, mas teoricamente nunca chega a zero. A lei é I = I₀·e^(−μ·x), onde I₀ é a intensidade que entra, μ o coeficiente de atenuação linear do material (depende do material e da energia da radiação) e x a espessura. Isso tem uma consequência prática profunda: não existe blindagem que bloqueie 100% dos raios gama — só se reduz a um nível aceitável, daí o conceito de camada semirredutora. Materiais densos (chumbo, tungstênio, concreto baritado) têm μ alto e blindam com menos espessura. O cálculo é a base do projeto de salas de radiologia, bunkers de radioterapia e blindagens de fontes industriais. Informe a intensidade inicial, o coeficiente de atenuação e a espessura.
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Half-Value Layer (HVL)
Compute the half-value layer (HVL), HVL = ln(2)/μ, the material thickness that reduces the radiation intensity by half, from the linear attenuation coefficient (μ). It is the practical way to specify shielding: one HVL cuts 50% of the radiation, two HVLs cut 75%, and so on. Dense materials like lead have a small HVL. Enter the linear attenuation coefficient.
Inverse Square Law (Radiation)
Compute the radiation intensity at a new distance from a point source, I₂ = I₁·(d₁/d₂)², by the inverse square law: intensity falls with the square of distance. Doubling the distance reduces the dose to a quarter — which is why distance is one of the three basic radiation-protection defenses (time, distance and shielding) and the most effective and cheapest. Enter the initial intensity and distance and the new distance.
Gamma Exposure Rate
Compute the exposure (or dose) rate of a point gamma source, X = Γ·A/d², from the exposure-rate constant (Γ, specific to the radionuclide), the source activity (A) and the distance (d). It combines the source strength with the inverse square law, allowing you to estimate the dose received at a given distance — fundamental in planning tasks with radioactive sources. Enter the gamma constant, the activity and the distance.
The results provided by this tool are for general informational and educational purposes only and do not constitute professional, financial, medical, legal, tax or accounting advice. Always confirm important decisions with a qualified professional and official sources.