Environmental guidance for your business in Northern Ireland & Scotland

What are radioactive substances?

What are radioactive substances?

Radioactive substances include radioactive material and radioactive waste. In Northern Ireland different legal controls apply to handling radioactive material and dealing with radioactive waste. In Scotland radioactive materials and radioactive waste are covered by the same regulations.

Radioactive material

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

The regulations will not apply to your business if the concentration of radioactivity in the materials that you keep or use is below the levels set out in:

Northern Ireland: Schedule 1 of the Radioactive Substances Act 1993.

Scotland: Schedule 8 Part 6 of the Environmental Authorisations (Scotland) Regulations 2018

This applies both when the materials are naturally occurring radioactive materials (NORM) and when they have been man made.

 If the concentration of radioactivity in the materials you keep or use is below the levels set out in the regulations, then you are “out of scope” of the regulations and you do not need to contact your environmental regulator. You should still make sure you comply with your Duty of Care when dealing with wastes.

If you keep or use radioactive materials that are above the levels set out in Schedules listed above, or they are not naturally occurring radioactive materials, you will need:

  • In Northern Ireland: a certificate of registration or an exemption order.
  • In Scotland: an authorisation

Types of radioactive materials

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

  • diagnosing and treating disease
  • controlling industrial processes
  • industrial radiography
  • scientific research.

Different types of radioactive material, including open and sealed radioactive sources, are used for different activities.

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

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.

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

In Scotland you must have the correct authorisation if you manage mobile radioactive apparatus.

Radioactive waste

Radioactive waste includes certain substances which would be radioactive material if they were not waste, or substances which have been contaminated by radioactive material or other radioactive waste. It can be in a solid, liquid or gaseous form.

Radioactive waste may include contaminated clothing that needs to be disposed of, laboratory wastes from the use of open radioactive material or a sealed source which is scrap.

There are four types of radioactive waste:

  • high-level waste that contains sufficiently high levels of radioactivity so that heat is generated, eg waste created by reprocessing spent nuclear fuel
  • intermediate-level waste that contains higher levels of radioactivity than low-level waste but without the heat generation that occurs in high-level waste, eg redundant sealed sources
  • low-level waste that is within specified concentrations of radioactivity, eg everyday items such as paper or plastics contaminated by radioactivity
  • very low-level waste that is below a specific concentration of radioactivity, eg laboratory and medical equipment used to handle radioactive material.

Radioactive substances users at non-nuclear sites are only likely to produce very low-level or low-level radioactive waste.

Further information

Northern Ireland Environment Agency (NIEA): Radioactive substances

Scottish Environment Protection Agency (SEPA): Radioactive substances

In this Guideline

What are radioactive substances?

Radioactive materials out of scope of the regulations

Regulation of radioactive substances in Northern Ireland

Regulation of radioactive substances in Scotland

Other radioactive substances regulations

Radioactive substances environmental legislation

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