To get out of these map with Radiation you must have on the following:
Primary - Anything you'd like.
Secondary - Anything you want.
Equipment - Tactical Insertion
Flash bangs, Smoke grenades, and Stun grenades aren't needed at all.
Perk 1 - Marathon - not required but, makes it easier.
Perk 2 - Lightweight - not required but, makes it easier.
Perk 3 - Anything you want.
Death Streak - Pain Killer
In the Map Wasteland go to the side with the whole radiation field where the little radiation signs are lay down tactical insertion and kill yourself or have your friend kill you until you get to you second death then lay down the tactical insertion right next to the field can't be where you here the Radiation sound and let someone kill you then once you have Pain Killer start sprinting into the Radiation field the Pain Killer should protect you for a while once you start slowing down from the Radiation start jumping and sprinting then after a while you make it through all the Radiation you can then start walking freely through the field of Radiation. You can then snipe off any Enemies running on that side to flank your friends if your in a Public Match.
This same technique can be used at the Afghan Radiation areas to get out of the Map. Plus, in Afghan there are Rocks that you can go inside to hide in but, the Afghan out of the Map glitch isn't the best since your in a Corner.
Remember, all glitches are for Educational purposes just for fun not to abuse.
If you'd like more Information or a Online Tutorial you can contact me on Xbox Live as UnFinishedSins.
I also will make a video on it later as well.