Ionising radiation

Ionising radiation Ionising radiation

HSENI is one of a number of public bodies which regulate work that causes or could cause radiation exposure of workers, the public or both. HSENI’s inspectors advise, inspect, investigate and enforce in a flexible and proportionate way so that radiation exposure of employees and others, arising from work activities, is adequately controlled.

Introduction to radiation in the workplace

Every day in Northern Ireland, a wide range of radiation types are used in industrial, medical, research and communications applications.

Some of these applications cause harmful exposure risks that must be effectively controlled. This page explains how those controls can be put in place.

The main types of radiation

Radiation is generally classed as either ‘ionising’ or ‘non-ionising’. Ionising radiation generally has more energy than non-ionising radiation.

Ionising radiations include:

  • x-rays
  • gamma rays
  • particulate radiation (alpha, beta and neutron radiation) produced from x-ray sets or radioactive substances

They are typically used in:

  • medical exposures
  • industrial radiography equipment
  • gauges used in industry for process control

They may also be produced from naturally occurring radioactive substances, including radon gas.

Non-ionising radiations include:

  • radiofrequency and microwaves, for example from plastic welding and some communications transmitters
  • infra-red, for example from very hot, glowing sources in glass and metal production
  • ultraviolet (UV) rays, for example from welding or the sun
  • visible radiation from high-intensity light sources, for example lasers
  • electromagnetic fields (EMFs)

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. HSENI 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 (does not apply to Northern Ireland)

The transport of radioactive substances is regulated by the Northern Ireland Environment Agency (NIEA). However, employers will also need to notify, register or gain consent from HSE where these requirements apply.

The main legal requirements enforced by HSENI are detailed in the following publication:

The hazards:

  • ionising radiation can cause dermatitis, burns, cell damage, cataracts, changes to blood
  • microwaves and radio frequencies can cause heating of any exposed part of the body
  • infra-red rays can cause skin burns and cataracts
  • UV light can cause skin burns, skin cancer, conjunctivitis and arc eye
  • lasers can cause permanent, severe damage to the eye and skin
  • exposure to ionising and UV radiation can damage DNA and can cause health effects, such as cancer, later in life - the risks are small for low levels of exposure but exposure to high levels of ionising and non-ionising radiations can cause acute effects such as burns, tissue and organ damage

Notification, Registration and Consent

Please see below for an overview on how to notify, register or apply for consent to work with ionising radiation.

Links on how to Notify, Register and apply for Consent are also provided:

Reporting a material change after consent has been granted

An employer must immediately notify HSE of any material change to the work practice which would affect the particulars provided with the application for consent.

For more information please see the following link:

Further Guidance

For more information on Ionising Radiation (IR), please see the following links below:

Contact us

If you need more information or guidance involving Ionising Radiation, please contact us via the following email address or telephone number:


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