Radiation and Nuclear Energy

What is radiation?

Radiation is energy. It travels as waves or particles. It is everywhere in the universe, coming from rocks, the sun, and the stars.

You can sense some types of radiation, such as light and heat. Other types, such as radio waves and ultraviolet, require special instruments to detect.

When radiation is powerful enough to knock electrons from atoms, it is called ionizing radiation. It can damage materials and living tissue. This means that the nuclear industry, which works with ionizing radiation, has a special responsibility to protect you.


Do nuclear reactors produce radiation?

Nuclear reactors can produce four main types of ionizing radiation:

  • Alpha particles are the nuclei of helium atoms. These particles are large and move slowly. They cannot penetrate your skin.
  • Beta particles are fast-moving electrons or positrons that can penetrate skin, but are stopped by materials such as plastic.
  • Gamma rays are photons – which means that, like x-rays, they are a form of light, but with even higher energy; gamma rays can be stopped only by dense metals, such as lead.
  • Neutron radiation is made up of very high-energy particles, and requires materials that are rich in hydrogen, such as concrete or wax, for shielding.

Small amounts of ionizing radiation are also produced wherever there are nuclear materials – in mining and milling operations, for example.

Is radiation dangerous?

Without proper protection, or “shielding,” high doses of ionizing radiation can damage human tissue and cause serious illnesses.

Research has found no measureable health effects in people who experience radiation doses below 100 millisieverts per year (mSv/year). Above this level, cancers and other illnesses become more likely.

Most people experience ionizing radiation at levels well below the safety limits. Almost all of it – an average of 2.4 mSv/year – comes from the environment: the gradual decay of atoms in the Earth, natural radon gas, and from space. Medical procedures such as x-ray scans can add to the dose.

Nuclear power plants also add to the total dose – barely. They emit less than one one-thousandth of the radiation you already receive. The food you eat produces more than 100 times this amount.


Who makes sure Canadians are safe from radiation?

Radiation from Canadian nuclear operations – from mining uranium, to operating power plants, to disposing of used fuel – is low because Canada’s nuclear industry is one of the most regulated and monitored industries in the world.

The Canadian Nuclear Safety Commission (CNSC), the independent nuclear regulator, supervises operations at Canada’s nuclear facilities. It has staff at every nuclear power plant in Canada. It regularly inspects every nuclear operation to make sure it keeps radiation at safe levels for workers, the public, and the environment. The CNSC also looks at plans for new nuclear projects – from mines to disposal sites – and ensures that they are safe too. The CNSC has the power to shut down any operation that it thinks is unsafe.

The Canadian nuclear industry plays a role too, working to meet and exceed the requirements of the CNSC, and building on decades of experience in handling nuclear materials safely.


Canadian Nuclear Association, https://cna.ca/.