Radiation in varying forms has been developed and used in medical and industrial applications ever since the discovery of x-rays by Wilhelm Roentgen in 1895. This increased with the pioneering work in the use of Radioisotopes for cancer treatment by Marie Curie in the early part of the 20th century.
X-rays and Gamma-rays are high energy forms of radiation used as an effective diagnostic and treatment tool.
Radioactive materials are naturally occurring substances in various forms used for diagnosis and treatment.
Both types of radiation sources are potentially dangerous and have to be used and contained to limit unnecessary exposure. Intentional irradiation of people, including in diagnostic and therapeutic applications, is required to be justified by balancing the potential benefits against the harmful exposure to ionising radiation.
Radiation protection is an essential requirement to protect all staff regularly working in the vicinity of the radiation source. This protection is also necessary to limit the level of radiation received by patients whilst ensuring effective diagnosis or treatment.
In simple terms X-ray and Gamma-ray radiation shielding can be achieved using any dense substance whilst the shielding of fast neutrons requires materials of a lower atomic mass and higher absorption cross section. This can include several common materials such as bricks, concrete, sand and steel.
Where space permits, concrete, to a carefully controlled density, is also the most cost effective shielding material for walls of high energy treatment units.
For all other applications sheet lead and associated compounds e.g. lead glass, lead PVC and lead acrylic (Premac®) are the most commonly used materials.
We also offer Premadex® as our unique neutron shielding material.
Read More: Structural X-ray Protective Shielding Read More: Neutron Shielding Read More: MRI Shielding Read More: Shielding for Non-Destructive Testing Read More: Shielding Materials
Role of the Radiation Protection Adviser (RPA)Top
Specialist advice is essential to minimise any potential radiation hazard. From the initial design to the commissioning and ‘release to use’ on completion, each site has to be individually assessed by a qualified radiation physicist.
The accredited Radiation Protection Advisor (RPA) for a particular hospital, trust or industrial facility will:
- Identify potential dangers
- Confirm structural shielding requirements
- Advise on work practices and develop local rules
- Consider other precautions to ensure the safety of staff, visitors and patients
They may also advise on room layouts in conjunction with the equipment supplier.
For all types of shielding it is necessary to make provision for any unavoidable breaches and cut-outs in the shielding e.g. door and window openings, ducting and other services.
MRI rooms require totally different types of shielding against:
- Radio Frequency (RF) waves cause interference to the magnetic field from the scanner producing artefacts within the images.
- Outside interference from large moving steel objects (e.g. lifts/vehicles) can also have a detrimental effect to the imaging.
- Strong magnetic fields can endanger people and damage equipment (e.g.pacemakers/monitoring equipment) if not adequately confined to the scanner room.