Radiation is a form of energy that is produced
from several sources and travels as rays, waves or particles. There
are two general categories of radiation: non-ionizing
and ionizing. Non-ionizing radiation
comprises several types, including microwaves and ultraviolet (UV) rays. Ionizing
comprises several types, depending on whether the radiation
travels as a particle or rays. The most common types of ionizing radiation
emissions are alpha, beta, x-rays and gamma ray.
Alpha particles can be shielded by human skin, but they can still
enter the body through a cut in the skin, inhalation and/or ingestion.
Beta particles can also be shielded by skin, but some need a thicker
shield (like wood) to prevent them from entering the body. Just
like alpha particles, beta particles can also cause serious damage
to health if they are inhaled or ingested. Gamma rays are a highly
penetrating type of radiation. They can penetrate paper, skin,
wood, and other substances. To protect yourself from gamma rays,
you need a strong shield such as a concrete wall. X-rays are also highly penetrating, but less than gamma rays.
Since certain types of radiation occur naturally, people
receive some background radiation exposure every day. One example
of this natural exposure is sunlight. There are several sources of
man-made background radiation exposure, such as household appliances
(including television sets and microwave ovens). However, beyond
these expected levels of exposure, there are certain industries and
occupational settings that can pose a risk for increased radiation
exposure. Some of these jobs include: x-ray technicians; nuclear
power plant workers; and uranium miners and processors.
Exposure to radiation can lead to short or long-term health side effects, depending
on the type of radiation, the duration of exposure, route and amount of radiation
absorbed. Short-term effects can include nausea or skin burns. Long-term effects
can include damage to the lungs, bone marrow, and thyroid gland. Radiation exposures
can also cause certain types of cancer. Since there are no tests to detect early
signs of disease caused by exposure to radiation, monitoring of potential exposure
in higher risk occupational settings is vital.