Skip to content

Ionising radiation is used in a variety of projects within St George's, University of London. These range from metabolic studies to the use of radionuclides as tracers.

All work involving  the use of radionuclides is regulated by the Environment Agency.

The use of ionising radiation is covered under the Ionising Radiation Regulations 2017. The use and holding of radioactive substances is also covered under the Environmental Permitting Regulations 2016.

Under these two regulations departments are required to produce a risk assessment of the work that involves the use of radionuclides. Departments must also ensure that a Radiation Protection Supervisor (RPS) is in place and able to communicate information to the local staff and deal with local issues.

Each lab must have specific Local Rules for the use of radionuclides to take into account the different materials handled. Download  these generic local rules (Word), which can be customised for each area.

All staff must keep accurate records of the radionuclides used and their method of disposal. Download the procedure for disposing of radioactive waste (Word). Download the form for logging the disposal of radioactive materials (Word).

In order to help individuals comply with the rules and regulations that govern the use of radionuclides with the UK, the Safety Health and Environment Office has produced a set of documents.

Control of the use of radionuclides within St George's, University of London is undertaken by the Radiation Safety Committee which meets three times a year. 

All users of radioactive open (unsealed) sources must be familiar with the Radiation Management System for Open (unsealed sources) (SHEP 29-A) (Word) and the Procedure for the Disposal of Radioactive Waste (SHEP 35) (Word).

All users of sealed sources must be familiar with the Radiation Management system Sealed Sources (Category 5 or exempt sources) SHEP29-B (Word).

All projects involving the use of radionuclides must be registered with the Radiation Protection Officer and with the Safety, Health and Environment office. Download the project registration form (Word) for working with open sources and or electrically generated ionising radiation.

Advice on the completion of the forms can be obtained from the SHE Office. The SHE office can be contacted on extn 0637 or 5166. 

New workers must be registered before work commences by filling out the new workers registration form (Word). 

All orders for Radionuclides must be placed using the procedure for Ordering, Receipt, Handling and Checking of Radioative Material given in the SHEP 30 document (Word).  

The amounts of each radionuclide must be logged and the amount used each month used notified to the Radiation Protection Officer. Download the stock record form (Word).

All areas must be monitored and decontaminated during and after work. 

Laboratories that are being taken out of service after the conclusion of experiments involving the use of radionuclides or rooms that are going to be refurbished must be decontaminated and decommissioned. Download the procedure (SHEP 44) detailing the actions that have been taken and the final monitoring readings (Word).

Emergency Actions

Download the procedure (SHEP 40) detailing the actions to take if radioactive materials are lost or spilt (Word).

The specific local rules for the area must be followed at all times. 

Information on types of ionising radiation

View all Close all
Particulate radiation
Alpha particles

These are Helium nuclei and are comprised of two protons and two neutrons. They can be stopped by a sheet of paper. They are a particular hazard if they enter the body. 

Beta particles

These are free electrons. They can be stopped by a 10mm sheet of acrylic. It is important to chose a shield that is low density to prevent the generation of Bremsstrahlung.

Electromagnetic radiation
Gamma rays

This is high energy electromagnectic radiation produced by the nucleus. It can be shielded by lead or lead acrylic.


This is high energy electromagnectic radiation caused by the rearrangement of the electron oribitals of atoms. Lead shielding is commonly used.

St George's, University of London is authorised to hold the following radionuclides. Handling information can be obtained by clicking on the radionuclide of interest.

GE Healthcare have produced 10 golden rules of working with radionuclides (PDF) that give information on safe ways to handle material.

Principles of Radiation Protection

All emissions are in three dimensions and exposure to other workers should be considered when deciding on how to protect yourself and other individuals. 

There are three main ways of protecting individuals when using radionuclides. 


Reduce the length of exposure to the material.


The greater the distance between you and the source the lower will be level of the exposure. Radiation exposure is subject to the inverse square law. A doubling of the distance will result in a reduction of exposure by 75%.


Appropriate shielding can reduce the amount of radiation that you receive. Care should be taken to select shielding that will not stimulate the emission of Bremsstrahlung.

The risk assessment for the project will determine the best method of protecting yourself and people and should determine the best available technology to use.


Find a profileSearch by A-Z