Table 2.
Iodine-125 seeds used for exposure measurements.
| Type | Number of seeds | Apparent activity1 (“mCi”) | Assay date |
|---|---|---|---|
| First series | |||
| Gold-marker | 4 | 60 | 1980/12/01 |
| No marker | 4 | 142 | 1982/09/06 |
| Silver-wire | 5 | 114 | 1981/06/01 |
| Second series | |||
| Gold-marker | 6 | 84 | 1983/02/21 |
| No marker | 4 | 103 | 1983/03/07 |
| Silver-wire | 6 | 95.4 | 1983/02/21 |
1
The apparent activity, as determined by the 3M Co., is a measure of the effective radiation output from the seeds and is independent of seed wall thick-ness or source self-absorption. The actual activity in the seed is greater than the apparent activity. The apparent activities are taken from the labels on the 3M lead acontainers. The 3M Co. has used the term “mCi Comp.” for apparent activity.