Managing radioactive substances

What are radioactive materials?

Radioactive material includes substances or articles that are radioactive, or have become radioactive through non-natural processes, for example at a nuclear reactor.

There are two main types of radioactive substances:

  • open radioactive sources, also called unsealed sources
  • sealed radioactive sources, also called closed sources

Radioactive materials are used by many organisations and businesses. For example, hospitals, research organisations, radiographers and process industries use radioactive materials for:

  • diagnosing and treating disease
  • controlling industrial processes
  • preventing static electricity
  • industrial radiography
  • scientific research

Different types of radioactive material are used for different activities.

Open radioactive sources

Open sources are radioactive materials that you can easily divide, disperse or dilute. They can be in a liquid, gaseous or sometimes solid form. Open sources include radioactive laboratory chemicals and radiopharmaceuticals.

Open radioactive sources can potentially contaminate other material through leakage or leaching. You must store all open radioactive sources securely.

Sealed radioactive sources

Sealed sources have a structure which prevents radioactive material from leaking during normal use. If you use sealed sources incorrectly you could cause radioactive contamination.

Sealed radioactive sources are categorised according to their hazard or risk as:

  • high activity sealed sources (HASS)
  • sources of similar potential hazard to HASS
  • category 5 (low hazard or risk)

A sealed source may take the form of a welded steel capsule, or a homogenous, laminated, electrodeposited or foil source.

HASS present a greater hazard to the environment and human health than other sealed sources. HASS may include sterilisation sources, hospital radiotherapy sources, industrial radiography sources, density and moisture gauges and some industrial process control gauges.

Mobile radioactive apparatus

Mobile radioactive apparatus includes equipment, appliances or other things that are portable and classed as radioactive material. They may be used for:

  • testing, measuring or investigation
  • releasing radioactive material into the environment or introducing it into organisms

Mobile radioactive apparatus may contain sealed or open radioactive sources.

You must have a certificate of registration if you use or keep mobile radioactive apparatus, unless you are covered by an exemption.