Ionising and non-ionising radiation
The main difference between ionising and non-ionising radiation is that ionising radiation carries more energy.
Ionising radiation includes:
- X-rays
- gamma rays
- radiation from radioactive sources and sources of naturally occurring radiation, such as radon gas
Ionising radiation has many uses in industry, such as energy production, manufacturing, medicine and research and produces many benefits to society. However, it is important that the risks of ionising radiation are managed sensibly to protect workers and the public.
Non-ionising radiation includes:
- visible light
- ultra-violet light
- infra-red radiation
- electromagnetic fields
Find out more about non-ionising radiation
Where ionising radiation occurs
Ionising radiation occurs as either electromagnetic rays (such as X-rays and gamma rays) or particles (such as alpha and beta particles). It occurs naturally (for example from the radioactive decay of natural radioactive substances such as radon gas and its decay products) but can also be produced artificially.
How people can be exposed
People can be exposed externally to radiation from a radioactive material or a generator such as an X-ray set, or internally by inhaling or ingesting radioactive substances. Wounds that become contaminated by radioactive material can also cause radioactive exposure.
Everyone receives some exposure to natural background radiation and much of the population also has the occasional medical or dental X-ray. HSE is concerned with the control of exposure to radiation arising from the use of radioactive materials and radiation generators from work activities. This is to ensure that workers and members of the public are not harmed by these activities.
The use of ionising radiation includes the use of radioactive materials and radiation generators from these work activities:
- manufacturing, food production and waste processing
- construction
- engineering
- oil and gas production
- non-destructive testing
- medical, veterinary and dental sectors
- education and research establishments (for example universities and colleges)
- nuclear
The nuclear industry and most transport of radioactive substances is regulated by the Office for Nuclear Regulation. However, employers will also need to notify, register or gain consent from HSE where these requirements apply.
The main legal requirements enforced by HSE are detailed in Approved Code of Practice and guidance (L121).