But one critic is questioning whether the industry and the Canadian Nuclear Safety Commission have gone far enough in preparing for potential disasters, particularly in light of climate change.
Shawn-Patrick Stensil, a nuclear industry observer with Greenpeace, said while the technical changes mandated by the commission are good there also needs to be a new mind set in the nuclear industry after what happened at the Fukushima Daiichi facility.
Using a recent licence renewal hearing for the Bruce nuclear plants in Ontario as an example, he said discussions on tornado strengths were inadequate and more severe weather must be considered as a result of climate change.
"Fukushima should be a warning that we should be looking at these new, more extreme weather events in the risk assessments of all plants globally, and we haven't done that yet," Stensil added.
Ramzi Jammal, executive vice-president of the commission, said it launched a review of Canadian nuclear power plants shortly after the March 2011 accident at Fukushima. Two years later it produced a report, and identified changes that must be completed by the end of this year.
"We need to expect the unexpected," he said.
Before Fukushima, Jammal said the emphasis in the nuclear industry was on design and prevention, but now it's on prevention and mitigation.
"Now we're saying accidents are going to occur. We are going to design and put into place emergency measures to deal with off-site consequences," he said.
The effort is to make nuclear power plants completely self-sufficient in situations that would stress a facility beyond most reasonable and probable scenarios, Jammal said.
He said that means making each facility able to provide its own back-up power, cooling water and other key safety measures to protect a reactor in the event of earthquakes, tornadoes, blackouts, and even terrorism. They need to be self-sufficient for three days to a week, depending on how remote the facility is located.
At New Brunswick's Point Lepreau nuclear power plant, it has meant a number of measures including increasing the number of diesel generators to four from two, adding a new building for emergency equipment, installing a large diesel storage tank, and adding pumps and hoses to ensure a supply of water to maintain cooling of radioactive fuel.
NB Power president Gaetan Thomas said many of the changes began before Fukushima when Point Lepreau was going through a major refurbishment to extend its lifespan by at least another 25 years.
"We were able to do tens of millions (of dollars worth of work) in the refurbishment, specifically in response to some potential beyond-design-basis accidents, before Fukushima occurred," he said.
That work included seismic upgrades to make sure piping and other equipment would be able to survive a strong earthquake.
Thomas said they've tried to take into account everything that could affect the facility.
"What would be the highest waves that could be generated on a tsunami at Point Lepreau? We look at wind. We look at a combination of events. We look at loss of power supply," he said.
Jammal said similar reviews and work have been done at nuclear facilities across Canada and they've worked to standardize equipment, such as the fittings for water hoses so that crews from one plant can assist other facilities and have the right gear.
The investigation into the Fukushima accident determined that the direct causes were all foreseeable and that the plant was not capable of withstanding the earthquake and tsunami.
Stensil said the industry in Canada must not dismiss possible events because they have a low probability of happening.
There has also been little examination by the nuclear safety commission of an accident involving multiple reactors, said Stensil, who is based in Toronto.
"We have 10 reactors in the GTA (Greater Toronto Area). They've never provided data on whether emergency planning can scope with that scale of accident," he said.
The commission will present a report on Canada's nuclear power plants in August, which includes status updates on each facility.
Point Lepreau is planning a major emergency preparedness exercise in November that will be monitored by more than 30 departments and agencies.
"We will be testing a lot of these response capabilities, and out of that there will be some lessons learned and improvements that we will implement and also share with our partners in the industry," Thomas said.Suggest a correction