Nuclear power was first unleashed in a wave of destruction at Hiroshima and Nagasaki in 1945. As a result of the explosion of the atomic bombs over these Japanese cities, hundreds of thousands of people lost their lives. Many of them were killed by the radio active waves released by the bombs and even in peacetime people can still be killed by this radiation.

The seriousness of the effect of radiation depends on various factors. These include the size of the radioactive dose received by the body, the duration of the exposure to the radiation, the type of radiation involved and the part of the body affected.

Normally the body can restore and repair any damage done to it but when radiation destroys the cells and tissues they cannot by replaced.

For this reason people who work in scientific laboratories and industries dealing with radioactive materials must be carefully protected with special clothing and equipment and have frequent health checks.