https://phys.org/news/2018-07-scientists-rio-scale-alien-encounters.html

First developed in 2001, the Rio Scale is a tool used by astronomers searching for extraterrestrial intelligence (ETI) to help communicate to the public 'how excited' they should be about what has been observed. The Scale measures the consequences for humans if the signal is from aliens, as well as the probability that the signal really is from aliens, and not a natural phenomenon or human-made. The scale gives a score between zero and ten, so that the public can quickly see how important a signal really is.

"The whole world knows about the Richter Scale for quantifying the severity of an earthquake; that number is reported immediately following a quake and subsequently refined as more data are consolidated," said Jill Tarter, co-founder of the SETI Institute. "The SETI community is attempting to create a scale that can accompany reports of any claims of the detection of extraterrestrial intelligence and be refined over time as more data become available. This scale should convey both the significance and credibility of the claimed detection. Rio 2.0 is an attempt to update the scale to make it more useful and compatible with current modes of information dissemination, as well as providing means for the public to become familiar with the scale."