Table 3.
Distribution of the doses to lung, cumulated over all modes of exposure and the entire careers of the Mound workers monitored for radiation (Boice et al. 2014).
| Career lung dose (mSv)a,b | Number of workers | Percentage of workers |
|---|---|---|
| <10 | 2,285 | 48.9 |
| 10 – 99 | 1,482 | 31.7 |
| 100 – 499 | 683 | 14.6 |
| 500 – 999 | 145 | 3.1 |
| ≥1,000 | 77 | 1.7 |
| All | 4,672c | 100 |
In this table a radiation-weighting factor of 1 was assumed for the alpha particles from 210Po and plutonium isotopes; a radiation-weighting factor of 10 was assumed for the neutrons. For the analyses other assumptions as to the relative biological effectiveness of alpha particles were made, i.e. weighting factors for the absorbed dose of 10 and of 20.
On average, about 75% of the lung dose is due to high-LET radiation (intakes of 210Po), the remainder of the lung dose being due to low-LET radiation (external irradiation from photons).
Excluding 305 workers who were not monitored for external irradiation and were subjected to very low levels of doses from internal irradiation.