What is the primary characteristic of alpha radiation?

The primary characteristic of alpha radiation is that it is primarily an internal hazard. Alpha particles consist of two protons and two neutrons, making them relatively heavy and positively charged. Due to their mass and charge, alpha particles have limited penetration power and can be stopped by a sheet of paper or even a few centimeters of air.

This limited ability to penetrate materials means alpha radiation is not a significant external hazard; however, it becomes a serious concern when alpha-emitting materials are ingested or inhaled. Once internalized, alpha particles can cause significant damage to biological tissues in close proximity, making them particularly hazardous when they enter the body.

Thus, understanding that alpha radiation is primarily an internal hazard is crucial for assessing the potential health risks associated with exposure to radioactive materials.