when you ask whether business will halt and die if the system you are responsible for is down or suddenly absent
or
it is going to be a mild inconvenience.
I think, defined like this makes it less ambiguous
edit: fix msg
This is a great way to put it.
I also ask myself the question: "who are the rockstars" at a company. The folks that are celebrated.
If it isn't a developer/engineer, you aren't at a category 2 company.