For Gamma Radiation What Stops Its Penetrating Abilities. Your exposure amount can only be measured using a Geiger counter and to determine what can stop gamma radiation. Gamma rays are not particles but a high energy form of electromagnetic radiation like x-rays except more powerful. Beta particles are very much smaller and gamma rays have no mass. Gamma rays can pass through lead but arent very damaging.
At the same time this property makes gamma rays extremely hazardous. Gamma rays can be emitted from the nucleus of an atom during radioactive decay. However lead steel and concrete reduce the energy of these particles and hence stop their penetrating abilities. Gamma rays can pass through a thin sheet of lead with very little effect. Normally its emitted at almost exactly the same time. The collision will stop the particle going through the material.
Gamma rays are energy that has no mass or charge.
Shielding this very penetrating type of ionizing radiation requires thick dense material such as several inches of. See below a military end-user adopting this ensemble the gold-standard in radiation protection. However it may take a material with a greater thickness and density to stop beta particles. Because of their penetrating power gamma rays can be used for radiographing holes and defects in metal castings and other structural parts. Alpha beta and gamma. Normally you would need 3 meters of concrete to prevent gamma radiation from penetrating.