Disused sealed sources

Sealed radioactive sources are radioactive material that is permanently sealed in a capsule or container. They are common in many industries, including medicine, agriculture and research. 

When they fall out of use, we classify them as disused.

Volumes

Information in Table 9 and Figure 12 has come from waste holders, supplemented by Australia’s Joint Convention report for some states and territories. 

Numbers reported by most organisations have not changed significantly since 2021. Increases or decreases in numbers are generally due to:

• sources being taken out of service (and thus becoming disused)
• disused sources in storage being disposed or recycled. 

The large increase in the total number is due to the inclusion of all states and territories. This has come from either:

• direct reporting to ARWA
• the Joint Convention report.

In 2021, the report only included states and territories that reported data directly to ARWA.

Most of the sealed sources contain americium-241 (7230 items, Figure 13). Many of these sources are disused smoke detectors that state and territory regulators have collected and stored.

We have not included disused sources containing other radionuclides that have even fewer numbers than those shown in Figure 13.

Uncertainties

• Many of the reported sources do not have an associated measurement date for the activity.
• Many of the reported activity values are the original source activity, with few having been measured recently. 

Therefore, the true current activity values for some sources are likely to be much lower. This is especially the case for short-lived sources. For these reasons, we have not included activity information for sealed sources.