Radiation weighting factor

Last revised by Matt A. Morgan on 3 Jul 2020

Citation, DOI, disclosures and article data

Citation:

Vajuhudeen Z, Morgan M, Radiation weighting factor. Reference article, Radiopaedia.org (Accessed on 19 Apr 2024) https://doi.org/10.53347/rID-79734

DOI:

https://doi.org/10.53347/rID-79734

Permalink:

https://radiopaedia.org/articles/79734

rID:

79734

Article created:

3 Jul 2020, Zemar Vajuhudeen

Disclosures:

At the time the article was created Zemar Vajuhudeen had no recorded disclosures.

View Zemar Vajuhudeen's current disclosures

Last revised:

3 Jul 2020, Matt A. Morgan ◉

Disclosures:

At the time the article was last revised Matt A. Morgan had no recorded disclosures.

View Matt A. Morgan's current disclosures

Revisions:

2 times, by 2 contributors - see full revision history and disclosures

Sections:

Imaging Technology

The radiation weighting factor (W_R) is a dimensionless constant that accounts for the relative biological effectiveness (RBE) of various types of ionizing radiation.

The radiation weighting factor is used to calculate the equivalent dose (H_T) by the following equation:

Absorbed dose (D_T) x radiation weighting factor (W_R) = equivalent dose (H_T)

The International Commission on Radiological Protection (ICRP) has published the latest set of numerical values of radiation weighting factors as below (as of 2007):

W_R = 1: photons, electrons
W_R = 2: protons
W_R = 20: alpha particles, fission fragments, heavy ions
W_R = variable: neutrons (determined by complex equations)