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Radiation Detection

You cannot see, hear, smell, taste, or touch radiation. You can only detect radiation with special equipment.

Detecting Non-Ionizing Radiation (NIR)

Since non-ionizing radiation is simply low-energy waves of the electromagnetic spectrum (radio waves or microwaves), detection is hard. The easiest way is to look for any nearby antennas, satellite dishes, or radio towers. Or, if you can listen to your radio, watch TV, have cell service or use wireless internet, Bluetooth, wireless mouse or keyboard you are definitely being exposed to NIR.

To measure the quantity of radio/microwaves you will need an EMF (electromagnetic field) meter. A very simple way to determine the wavelength of NIR is the length of the antenna.  As a general rule, the shorter the antenna, the more energized the waves. To pick up radio waves, an antenna must be the length of the longest wavelength. You can compare the antenna length to the electromagnetic spectrum chart to find the energy intensity.

Detecting Ionizing Radiation

Geiger CounterIonizing radiation can be measured very precisely — much more precisely than other potentially hazardous materials. One of the basic measuring instruments is the Geiger-Muller counter. The instrument consists of a detector set at the end of a probe with counting electronics.  This instrument counts the number of radioactive particles entering a sensitive detection chamber, and translates that signal into a needle movement on an analog dial or a value displayed on a screen.

The Geiger counter emits a click for every particle, so with only background radiation, the instrument clicks every few seconds. In a high radiation environment, it clicks rapidly in proportion to the radiation level. This way, the user gets a visible as well as audible measurement of radioactivity.

Some people receive exposure to radiation as part of their employment (radiologists and nuclear plant workers). Worker radiation exposures are carefully monitored to ensure that everyone’s exposures are kept as low as reasonably achievable (ALARA).  Individual film badges and personal dosimeters are useful for this purpose. In the film badges the amount of film darkening is a measure of the radiation received, so by analyzing the film, radiation exposure records for each individual worker can be kept. Personal dosimeters allow the workers to view their own radiation dose instantly by looking at a small scale magnified by the instrument.

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