School of Chemistry | Faculty of Science | The University of Sydney
Periodic Table (PDF) | Useful Data | Useful Formulas

Annual Radiation Dose

Want to estimate your annual radiation dose?

This calculator allows you to estimate your annual radiation dose due to background radiation. Fill in the form by selecting the appropriate entries on the drop down menus and by checking the boxes that are relevent to you. This calculator is intended for educational purposes only and no responsibility is taken for its accuracy.

Press the "reset" button to clear your entries.

radiation source


dose in μSv per year*

1. cosmic radition

      (a) cosmic radiation at sea level         260
      (b) additional dosage for higher locations
      (c) time spent in aeroplanes per year

2. terrestrial and atmospheric radiation

      (a) radiation from rocks and soil         260
      (b) house construction
      (c) food, water and air         400
      (d) fallout from nuclear weapons tests         40
      (e) live within 80 km of a coal power plant
      (f) live within 80 km of a nuclear power station

3. lifestyle

      (a) luminous LCD watch
      (b) porcelain crowns or false teeth
      (c) watch television regularly
      (d) use a computer regularly
      (e) share a bed regularly
      (f) smoke detector
      (h) go through X-ray bag check at airport
      (g) cigarettes smoked per day

4. health

      (a) plutonium-powered pacemaker
      (b) radioisotope procedure (eg thyroid scan)
      (c) body X-rays per year
      (d) dental X-rays per year

overall estimated dose



The sievert (Sv) is the most commonly used unit for measuring the effects of radiation on biological materials. A unit called the rad is used to measure the radiation absorbed dose, with 1 rad defined as the absorption of 0.01 joules of radiation energy per kilogram of tissue.

The damage caused by radiation is also affected by the type and energy of the radiation. To reflect this, the number of rads is multiplied by a factor Q which reflects the type and rate of radiation and the type of tissue. Beta, gamma and X-rays have Q = 1 whilst the more damaging alpha particles and neutrons have higher values. The rem is the roentgen equivalent man is the Q multiplied by the number of rads.

Finally, a sievert (Sv) is defined as 100 rem. Commonly, smaller units are used for everyday radiation such as the microsievert:
1 microsievert = 1x10-6 Sv = 1 mSv

Contact Us | Privacy | ©2024 School of Chemistry | last modified Wednesday, 18 November, 2009 :: top of the page ::