A sealed source is a radioactive compound that is:
- Sealed within an impermeable container (eg. 125I)
- A solid material that is unable to be dispersed (eg. 192Ir)
Specific Sealed Sources
- 12.1.1 - Iridium 192
- 12.1.2 - Iodine 125
- 12.1.3 - Palladium 103
- 12.1.4 - Caesium 137
- 12.1.5 - Strontium 90
Uncommon and Historical Sources
Radium-226 was the first source used in brachytherapy. It has a complex decay chain, including gaseous 222Rn, which presents a health hazard. It has fallen out of favour due to safer sources such as 192Ir and 137Cs.
Cobalt-60, perhaps more famous for use in external beam teletherapy, was also used in low dose rate form for intracavity and interstitial brachytherapy, similar to iridium, caesium and radium.