Asked by: Marci Requejo
science physics

How is HVL calculated?

Last Updated: 15th April, 2020

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Determine the attenuation coefficient of a material. This can be found in a table of attenuation coefficient or from the manufacturer of the material. Divide 0.693 by the attenuation coefficient to determine the HVL. The half-value layer formula is HVL = = 0.693/μ.

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Beside this, how is HVL calculated in radiography?

HVL is the thickness of material penetrated by one half of the radiation and is expressed in units of distance (mm or cm). HVL = 0.693 X Average Range = 0.693/µ. This shows that the HVL is inversely proportional to the attenuation coefficient.

Additionally, why is half value layer important? Half value layer. HVL is an important quality control test as it is used to measure whether or not there is sufficient filtration in the x-ray beam to remove low energy radiation, which can be damaging. It also helps to determine the type and thickness of shielding required in the facility.

Then, what is HVL in radiology?

Half-value layer (HVL) is the width of a material required to reduce the air kerma of an x-ray or gamma-ray to half its original value. This applies to narrow beam geometry only as broad-beam geometry will experience a large degree of scatter, which will underestimate the degree of attenuation. HVL = 0.693 / μ

What does half value layer mean?

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.

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