Environmental Radiation Monitoring

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Airborne Radiation Meteorology Radioactivity & Radiation Rainfall & Radiation FAQ

Radioactivity and Radiation

Radioactivity is different from radiation. Things, which emit radiation, e.g., alpha particles, electrons, and gamma rays, are called radioactive substances. While emitting radiation, radioactive substances change in form. A substance that has the ability to emit radiation is said to be radioactive.
Radioactivity levels decrease over time. The time required for the radioactivity of a substance to be reduced to half its initial value is called its half-life.

Fireworks sparkler
For example, if you think of radioactive substances represented in terms of a fireworks sparkler...

Radioactivity Level:
Effect on the Body:

ability of the sparkler to emit sparkles
sparkles emitted by the sparkler
time it takes for the sparkler to decrease to half its length
brightness of the sparkles (bequerels; Bq)

how hot the sparkles are when they hit the body
(seiverts; Sv)

Different Kinds of Radiation

Among radiation, there are various types including alpha particles, beta particles, gamma rays, and neutrons. X-rays are one kind of radiation. Depending upon the type of radiation, the ability for radiation to pass through materials varies.

A Comparison of Radiation in Our Everyday Lives

A Comparison of Radiation in Our Everyday Lives