Seine reopens to Paris swimmers after century-long ban

According to a Dutch article I read they are actually required (‘... Swimmers also have to use a yellow swimming buoy when going into the water.’)

I don't know, but this appears to be the floation product in question:

https://restube.us/

Kinda interesting, in the pictures in the article everyone seems to have a yellow floaty thingy. Anyone know if they actually require everyone to use one or if it's just a coincidence that everyone happened to have one when the pics were taken.