Early earthquake warning system launched in Quebec, eastern Ontario

Phone, broadcast alerts could arrive several seconds before shaking begins

A network of sensors that can provide crucial notice of a potentially serious earthquake is now up and running in Quebec and eastern Ontario.

Natural Resources Canada (NRCan) announced the expansion of the Earthquake Early Warning System on Thursday.

If an earthquake of magnitude five or higher is detected, the system kicks into action and transmits emergency phone and broadcast alerts similar to those for tornadoes or Amber Alerts.

Earthquake warning alert/Gian Paolo Mendoza/CBC

Alerts like this will now pop up on your phone if a potentially serious earthquake is detected in Quebec or eastern Ontario. (Gian Paolo Mendoza/CBC)

Those alerts could give several seconds of warning before the shaking begins, allowing people time to take shelter and protect themselves.

The department said it's also working on warning specific sectors so trains could be held, surgeries paused and bridges or tunnels closed, for example.

Along with western B.C., where the warning system was launched last year, NRCan said eastern Ontario and southern Quebec are at moderate to high risk of earthquakes.

A major earthquake in such urban environments could cause tens of billions of dollars worth of damage, NRCan said.

One earthquake above magnitude five has been recorded in Canada this year, according to Earthquakes Canada: a magnitude 5.2 off the coast of the Northwest Territories last month.

This region has recorded only three of that strength this century, in 2002, 2010 and 2013.

P and S waves

As the government explains it, the sensors first detect the initial deep energy radiating from an earthquake, known as the primary or P wave.

If it has the potential to cause damage, an alert is transmitted before secondary or S waves hit and cause damage.

In B.C. for example, the P waves of a quake about 600 kilometres away were detected about a minute before the S waves arrived.

People closer to a quake's epicentre may not get an alert in time, however.

WATCH: How to safely react when an earthquake strikes

Thumbnail courtesy of Gian Paolo Mendoza/CBC.

The story was originally written by and published for CBC News.