The San Marino Scale has been widely suggested as a method for assessing the risks we incur with deliberate transmissions from the Earth to other stars. Introduced by Iván Almár in 2005, the Scale is a work in progress that draws on the model of the Richter Scale, which quantifies the severity of earthquakes.
I find efforts like this interesting in an abstract sense. But my gut tells me that if there are inquisitive ETs out there then they'll almost certainly know about us already -- maybe not a lot, but enough to draw a useful composite portrait.
If there are any "berserkers" lurking in the depths, we're fucked.