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How to Calibrate a Geiger Counter

A Geiger-Muller counter, commonly shortened to Geiger counter, is a device used for measuring the level of radiation. Basically, it is a particle detector that shows whether an area or an object emits ionizing radiation. The main part of a Geiger counter is the tube inside it, filled with gas and with a certain amount of voltage applied. To determine if there is a source of radioactivity near and the exact level of radiation of it, you will need a calibrated Geiger counter. It is recommended that a Geiger counter should be calibrated every year.

Instructions

- 1
  Turn on the Geiger counter to start the calibration process. Note that it is not the Geiger-Muller tube inside the counter that needs calibration, but the circuits around it.
- 2
  Find and prepare a source whose level of radioactivity you will be measuring. This source has to be a material for which the exact level of radioactivity is known.
- 3
  Place the Geiger counter near the source, making sure the Geiger-Muller tube is facing the material directly. This position of the counter will assure that the material passes through the thin window and ionizes the gas inside.
- 4
  Read the result of the measuring on the Geiger counter. These devices have a common needle meter to get the exact number, but they also have a flashing LED light and a clicking sound that indicates the existence of radiation.
- 5
  Compare the reading you took from the Geiger counter with the number for the known source. If they match, the Geiger counter is already calibrated. If they don̵7;t, you will have to adjust the Geiger counter.
- 6
  Adjust the counter̵7;s circuit until you reach the exact reading for the known source. Now the Geiger counter is calibrated and ready to make accurate and precise readings.

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