You are correct. It is an assessing tool used by the USCG and other rescue teams/agencies in evaluating whether to go with a rescue operation or determine if you can change one of the factors to reduce the risk factor.

Severity x Probability x Exposure = Risk

For example I have a possible rescue:

Is this a rescue or recovery?
What is the risk vs. benefit ratio? (i.e. Life safety: willing to risk a lot to save a lot vs. recovery: willing to risk little to save little)

Do I have trained crew in that particular type of rescue?

Do I have enough trained personnel to perform the rescue?

Do I have the right equipment for this rescue?

Pete