ICU nurse:patient ratio

[RDH1, ADN, BSN, RN]

Anyone know where I could find printed recommended nurse to patient ratios for critical care? I am finding plenty of articles that show that a better nurse-to-patient ratio = higher quality of care and less patient deaths. However, I need something from a credible source (AACN, Joint Commission etc) that have numbers. I have done hours of googling and several more hours accessing peer review journals through paid university access.

For example, something that says "fresh CABG should be 1:1 until....." or "examples of 1:1 patients include therapeutic hypothermia, Gift of Life/Organ Donor" etc. Or, examples from certain hospitals would also work (I can't find published sample staffing matrix either). It seems that there is nothing "on paper" that says ICU nurses should only safely have 2 (or less) patients per nurse. I know this is not the reality in many ICUs and many are tripling now which is why I would like to have something substantive on paper as my hospital is looking to implement a different staffing model. What can I show them on paper that proves what types of patients should be singled (1:1), what types of patients can be doubled (1:2) and in what cases would it be safe to triple (probably never lol).

I did find the AACN's Synergy Model and some staffing articles from AACN but there were no numbers in it.

Thanks!