I also didn't fully understand if the context is:

- Ban ANY use of your personal chats / device at work (eg. your wife texts you to bring milk on the way home)

- Ban WORK communication (eg. My colleague don't understand recent commit I've made)

So the web really isn't explaining how things enforced or what is being done. I do know of some industries where you put your personal phone when entering specific locations or having stickers on cameras) but here I didn't fully understood the scope.

Yahoo messenger/BBM used to be popular when I was in banking and that's where banking was done. Then confirmed via email.

Now the idea is all banking related stuff is done on approved devices and clients so you can deal with retention(more like deletion) and loss.

And no personal chat clients too. If you're low enough on the pole, you don't even get to keep your personal devices with you.