I do this for the lifespan of each needle or more specifically each syringe. When at the inoculation phase whether it be LC, Spawn Bags, or jars and I am exposing an unopened sterilized needle to atmosphere for the first time (whether it be in-front of a flowhood or in a SAB with proper sterile procedure) I immediately push the end of the needle into the rounded end of an ear plug that is saturated with 70 percent iso. Pushing about halfway through the ear pug lengthwise. Logic here being that the buisness end is now isolated from the atmosphere. Then the flat end of the ear plug is held flush against the SSIP and the needle is pushed into the spawn. Barrel of the needle getting run through the iso and then squegeed by the SSIP on its way in. After injecting I keep the ear plug in contact with the SSIP and remove the needle back into it half way before lifting off the SSIP. I have had incredibly good results with this coupled with proper Sanitary and Sterile lab technique throughout the rest of the procedure. Im curious to here some community discussion on this. And before the up roar begins I regularly incorporate flame sterilization into my procedure. However I have used this on days where I am Noc'ing 50 - 100 cc's of the same innoculate and it has dramatically increased the speed of my workload with a shockingly low contam rate considering the dogma that is flame sterilization.