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What are the basic measures in radiation protection?

Shortening the time of exposure, increasing distance from a radiation source and shielding are the basic countermeasures (or protective measures) to reduce doses from external exposure.

Time: The less time that people are exposed to a radiation source, the less the absorbed dose.
Distance: The farther away that people are from a radiation source, the less the absorbed dose.
Shielding: Barriers of lead, concrete or water can stop radiation or reduce radiation intensity.

To reduce doses from intake of radioactive substances, the following basic countermeasures can be considered:

  1. shortening time of exposure to contaminants;
  2. preventing surface contamination;
  3. preventing inhalation of radioactive materials in air; and
  4. preventing ingestion of contaminated foodstuffs and drinking water.


Time and distance


Basic measures in radiation protection

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Last revision date: <19 Dec 2012>