Chordazone

Q: What’s the Difference Between Alpha, Beta and Gamma Radiation?
A: Everything in nature would prefer to be in a relaxed, or stable state. Unstable atoms undergo nuclear processes that cause them to become more stable. One such process involves emitting excess energy from the nucleus. This process is called radioactivity or radioactive decay. ”Radiation” and ”radioactivity” are often confused, the proper relationship is that ”radioactive atoms emit radiation.”

The three main types of nuclear radiation emitted from radioactive atoms are:

Alpha: These are actual particles that are electrically charged and are commonly referred to as alpha particles. Alpha particles are the least penetrating of the three primary forms of radiation, as they cannot travel more than four to seven inches in air and a single sheet of paper or the outermost layer of dead skin that covers the body will stop them. However, if alpha particle emitting radioactive material is inhaled or ingested, they can be a very damaging source of radiation with their short range being concentrated internally in a very localized area.

Beta: These are also actual particles that are electrically charged and are commonly referred to as beta particles. Beta particles travel faster and penetrate further than alpha particles. They can travel from a few millimeters up to about ten yards in open air depending on the particular isotope and they can penetrate several millimeters through tissue. Beta particle radiation is generally a slight external exposure hazard, although prolonged exposure to large amounts can cause skin burns and it is also a major hazard when interacting with the lens of the eye. However, like alpha particles, the greatest threat is if beta particle emitting radioactive material is inhaled or ingested as it can also do grave internal damage.

Gamma: Gamma rays are similar to x-rays, they are a form of electromagnetic radiation. Gamma rays are the most hazardous type of external radiation as they can travel up to a mile in open air and penetrate all types of materials. Since gamma rays penetrate more deeply through the body than alpha or beta particles, all tissues and organs can be damaged by sources from outside of the body. Only sufficiently dense shielding and/or distance from gamma ray emitting radioactive material can provide protection.

Bottom Line: All three of the primary types of radiation above can be a hazard if emitted from radioactive material that was inhaled or ingested. Protected food and water and even a simple inexpensive dust protector face mask can go a long ways to denying this route of entry. However, for the penetrating gamma rays, it is essential to be able to measure the strength of this type of radiation to then discover the best protected shielding and distance options available. (See our FAQ entitled Nuclear Blast & Fallout Shelters FAQ for an understanding of nuclear bomb effects, fallout, and effective sheltering options.) Also, in a shelter or home, besides revealing the safest locations there, knowing the intensity of the local gamma radiation outside will better indicate when it is again safe. Or, safe enough to perform a brief essential chore outside. More information on the specific physical damage caused by gamma radiation is below in the section entitled: Which Survey Meter Would Be Best For My Needs?

Possible effects of a catastrophic meltdownThe ”China Syndrome” refers to a hypothetical result of a catastrophic meltdown of a nuclear reactor. The scenario begins when something causes the coolant level in a reactor vessel to drop, uncovering part—or all—of the fuel element assemblies. Even if the nuclear chain reaction has been stopped through use of control rods or other devices, the fuel continues to produce significant residual heat for a number of days due to further decay of fission products. If not properly cooled, the fuel assemblies may soften and melt, falling to the bottom of the reactor vessel. There, without neutron-absorbing control rods to prevent it, nuclear fission could theoretically resume but, in the absence of a neutron moderator, may not. Regardless, without adequate cooling, the temperature of the molten fuel could increase to the point where it melts through the structures containing it. Although many feel the radioactive slag would stop at or before the the underlying soil, such a series of events could release radioactive material into the atmosphere and ground, potentially causing damage to the local environment’s plant and animal life.[6]