Canada's public emergency alert system is sending out a test Wednesday.

And while it's not a pleasant sound, it's one you need to hear.

It's meant to ensure safety officials can deliver urgent warnings to the public in times of disaster.

The test will be sent out to all provinces and territories, except Quebec, at 1:55 Wednesday afternoon. Quebec’s test is scheduled for an hour later.

The text alert is expected to activate on the radio, TV, and cellphones. 

This is the second test for the emergency alert system.

The previous one happened this past May, and came with widespread problems.