In terms of gamma and x-radiation, it's all about density, so osmium and iridium would be a little better than tungsten or uranium (for a given thickness), both of which are more effective (because denser) than lead.
Is osmium resistant to radiation?
In one direction is an infinite amount of lead, in the other direction is an infinite amount of osmium. The emitted photons pass directly into these metals and do not interact with anything else, nor are any other forms of radiation present.
What materials can block radiation?
Materials that block gamma radiation:
- Lead aprons and blankets (high density materials or low density materials with increased thickness)
- Lead sheets, foils, plates, slabs, pipes, tubing, bricks, and glass.
- Lead-Polyethylene-Boron Composites.
- Lead sleeves.
- Lead shot.
- Lead walls.
- Lead putties and epoxies.
