CosDNA question

So I'm trying to become more familiar with cosmetic/beauty "safety" rating websites beyond the one I've used mose in the past (EWG). I hear people reference CosDNA here but I can't find a lot of info on their site explaining what exactly their results indicate. I see the 5-point "safety" scale that they say is more about the long-term inpact on the skin, cells, or body. What I'm not fully understanding are the "acne" column and the "irritant" column. I assume that they both include scores based on a 5-point scale and I also assume that the acne column rates the likelihood of the ingredient to cause acne (?) and does the irritant column indicate the likelihood of the ingredient to irritate the skin (?) to irritate pre-existing blemishes (?) Can somebody explain this all to me?