Racked a batch to my secondary fermenter about 10 days ago. Noticed today I had not put the 3 piece airlock back on correctly. Forgot to put that floating dome shaped piece back over the opening. So basically, the batch has been exposed to the air for about 10 days now. It doesn't smell bad, and there's nothing forming on the surface of the wort, but I'm concerned about contamination. My hope is that there was still at least a small amount of active fermentation, and that the Co2 venting through that opening may have kept the air out, but I'm not sure whether to proceed or to just dump it. Thoughts?