All hell breaks loose

The website says it means when a secret gets out and things get bad.

Is this how it is really used in actual conversation? Sometimes, yes, but I've mainly just heard it when a situation gets really bad and everything goes wrong.

All his training is a pain, but when the **** hits the fan, it's a life saver.

It means when the situation gets seriously bad.
"Send lawyers, guns and money, for the sh*t has hit the fan." As the song goes.

It's the same as "all hell breaks loose."