Decommissioning of the Gentilly‑2 facilities
Protection of public and workers health
In Canada, natural ionizing radiation exposes people to a yearly dose of 1.8 mSv (millisieverts). Natural sources of radiation include solar cosmic rays, terrestrial radiation (the earth's crust and construction materials such as granite and brick), the food chain, radon, etc.
People are also exposed to radiation from human activity, such as medical examinations, airplane travel and industrial processes, which adds an average of 1 mSv per person.
The Radiation Protection Regulations drafted by the Canadian Nuclear Safety Commission (CNSC) limit the dose of radiation from activities licensed by the CNSC that may be received by members of the public to 1 mSv. The estimated annual dose received by representative members of the population in the Gentilly‑2 area has always been less than 1% of this prescribed effective dose limit.
The effects of exposure to ionizing radiation on the human body are dependent upon several factors: radiation type (alpha, beta, gamma), dose and duration.
According to a 2003 study by the Direction de santé publique of the Agence de la santé et des services sociaux de la Mauricie et du Centre‑du‑Québec, cancer rates in the area around Gentilly‑2 are no higher than elsewhere in Québec.
In 2004, the International Agency for Research on Cancer conducted a study on cancer risk in nuclear industry workers. Data from Gentilly‑2 was combined with data on nearly 600,000 workers in 15 countries. The study showed that in Canada, general mortality and cancer rates are lower and leukemia rates are no higher among nuclear industry workers than among the general population.
Exposure explained in figures
- A single flight from Montréal to Vancouver exposes passengers to a dose of radiation that is five times greater than what people living near a nuclear power plant are exposed to in a year.
- Medical X-rays expose patients to ionizing radiation that varies between 0.01 mSv (for a dental X-ray) and 10 mSv (for an abdominal scan)—between 10 and 10,000 times more exposure than a person living less than 2 km from a nuclear power plant.
Worker health and radiation protection standards
The health of Gentilly‑2 employees remains one of Hydro‑Québec's top priorities. As during operations, every worker has a medical follow-up and enjoys access to personalized health care. In addition, every worker wears a dosimeter to measure exposure to ionizing radiation.
CNSC limits for worker exposure are 50 mSv/year and 100 mSv/5 years. For Gentilly-2, Hydro‑Québec has set an even more restrictive administrative limit of 20 mSv/year. On average, workers are exposed to only 1 mSv.
Understanding ionizing radiation
To understand ionizing radiation, it is important to have a basic understanding of how nuclear reactions work.
