Table 4.
Tissue weighting factors recommended by the International Commission on Radiological Protection (ICRP) in 1991 and 2007. The tissues in parentheses mean the remainder tissues. The tissue weighting factor for the remainder tissues applies to the arithmetic mean dose of the organs for each sex.
| Tissue or Organ | ICRP 60 | ICRP 103 |
|---|---|---|
| Red bone marrow | 0.12 | 0.12 |
| Colon | 0.12 | 0.12 |
| Lung | 0.12 | 0.12 |
| Stomach | 0.12 | 0.12 |
| Breast | 0.05 | 0.12 |
| Gonads | 0.20 | 0.08 |
| Bladder | 0.05 | 0.04 |
| Esophagus | 0.05 | 0.04 |
| Liver | 0.05 | 0.04 |
| Thyroid | 0.05 | 0.04 |
| Bone surface | 0.01 | 0.01 |
| Brain | See below | 0.01 |
| Salivary glands | none | 0.01 |
| Skin | 0.01 | 0.01 |
| Remainder | 0.05 | 0.12 |
| (Adrenals) | (0.005) | (0.0086) |
| (Extra thoracic region) | none | (0.0086) |
| (Gall bladder) | none | (0.0086) |
| (Heart) | none | (0.0086) |
| (Kidneys) | (0.005) | (0.0086) |
| (Lymphatic nodes) | none | (0.0086) |
| (Muscle) | (0.005) | (0.0086) |
| (Oral mucosa) | none | (0.0086) |
| (Pancreas) | (0.005) | (0.0086) |
| (Small intestine) | (0.005) | (0.0086) |
| (Upper large intestine) | (0.005) | none |
| (Spleen) | (0.005) | (0.0086) |
| (Thymus) | (0.005) | (0.0086) |
| (Brain) | (0.005) | See above |
| (Prostate for male) | none | (0.0086) |
| (Uterus/cervix for female) | (0.005) | (0.0086) |