Nuclear Safety and Security

Why are nuclear safety and security important?

In 1952, the shut-off systems failed at one of the research reactors in Chalk River, Ontario, and operators made errors in how to deal with the problem. The reactor then had a partial meltdown, and cleanup took several months.

The industry learned from the accident, and made major changes to reactor design and operator training. Nuclear workers in Canada haven’t been exposed to dangerous levels of radiation since. In fact, no member of the public has ever been harmed by nuclear plant operations in Canada. Nor has there ever been a security breach at a Canadian nuclear plant.

Despite this impressive record, the Canadian nuclear industry continues to refine its safety and security. It is one of the most strictly regulated industries worldwide, under the leadership of the Canadian Nuclear Safety Commission (CNSC), the independent nuclear regulator.

How does the industry prevent accidents?

The top priority at Canadian nuclear plants is safety. At all plants, five major safety principles protect workers and the public:

Bruce Power control room operator. Source: Bruce Power.
  • All equipment is of the highest quality, and control systems are duplicated. If one fails, another takes over.
  • Control-room operators are carefully screened. An operator has about eight years of training.
  • All safety systems are regularly tested and inspected.
  • These systems are designed to shut the reactor down automatically if a major accident happens, while keeping the cooling systems running.
  • Each reactor sits in an airtight building with reinforced concrete walls, or is connected to a vacuum building, to prevent any radioactive steam from escaping.

How does the industry contain radiation?

Dosimeter. Source: Cameco.

Canada’s nuclear industry takes serious measures to protect the safety of anyone who handles or works near radioactive materials. For example, every nuclear worker carries a “dosimeter,” a device that measures radiation exposure. All facilities monitor contamination levels and radiation doses, and keep them as low as reasonably possible. Nuclear facilities also manage “sealed sources” – packages that shield nuclear substances used in medicine and industry from contact with people and the environment.

Safety measures apply along the whole supply chain, from mines and mills to reactors and storage. By conducting thousands of inspections each year, the independent nuclear regulator ensures that these measures are in place. It can suspend or cancel the operating licence of any facility that does not meet its high standards.

Is the nuclear industry secure?

Canada’s nuclear industry is devoted to peaceful purposes. Still, nuclear materials, and the importance of nuclear reactors to the power grid, could make them enticing targets.

Nuclear power plants and the national nuclear laboratories are extremely secure, protected day and night by highly trained and well armed response teams. All operators must pass extensive security checks. Regular threat assessments, drills, and exercises keep the security systems at peak performance. Appropriate security measures also apply to the whole industry.

Also, the nuclear industry works with the Canadian government to strengthen global security. It complies with international treaties to keep nuclear materials from reaching weapons programs around the world. And it takes part in international efforts to dispose of highly enriched uranium, which could be used to build nuclear weapons.

Bruce Power’s award-winning nuclear response team. Source: Bruce Power.


Canadian Nuclear Association,