Someone else mentioned a breaker lockout which will absolutely do what you've asked.
A similar idea is to get plug lockouts. It goes over the plug of the tool/machine you want to prevent from being energized. This would let you keep power on but the tools can not be powered on.
You want to search for lockout and/or loto. You can get locks that use the same key too.
Do not rely on those plastic key things that some tool companies put on their machines. They are stupid easy to bypass.