ICRP 103 tissue weighting factors (modified from ref 49)
| Tissue | Weighting factor |
| Gonads | 0.8 |
| Bone marrow | 0.12 |
| Colon | 0.12 |
| Lung | 0.12 |
| Stomach | 0.12 |
| Breast | 0.12 |
| Remainder tissues* | 0.12 |
| Bladder | 0.04 |
| Oesophagus | 0.04 |
| Liver | 0.04 |
| Thyroid | 0.04 |
| Bone surface | 0.01 |
| Brain | 0.01 |
| Salivary glands | 0.01 |
| Skin | 0.01 |
*The ‘remainder tissues’ refers to the combination of the adrenals, extrathoracic region, gallbladder, heart, kidneys, oral mucosa, pancreas, prostate, small intestine, spleen, thymus, uterus, lymph nodes and muscle. All of these tissues together are assigned a weighting factor of 0.12.
ICRP, International Commission on Radiological Protection.