I had never heard of such a thing. But it popped up when I was reading about the Crisis Text line on Kati Morton - Mental Health YouTube creator - Your Mental Health Community She has a pretty good plan that she uses but she also said you can Google "Safety Plans" and find many that you can print off. If your not sure what this plan is all about, like me, then I would suggest you watch her video on it. It explains it's purpose very well.
or
Google Kati Morton+Safety Plan