In the Core Rules and GM Toolkit there isn’t anything about armor mods that give radiation resist but I purchased the Fantasy Grounds Unity Fallout 2d20 plugin and it has a “lead lined” mod that works in the Torso, Arms, and Legs of normal armor and it gives 3 Resist VS Radiation.
Also, the only head armor piece that has radiation resist is the Cloth Sack… Is this how it’s meant to be or is this something else that got overlooked? Has this been addressed before by other people?