The United Nations Environment Programme (UNEP) just released a new plain language guide addressing the common questions:

• What is radiation?
• What does radiation do to us?
• Where does radiation come from?

The abstract (by UNEP):

This publication is based on the major scientific reports of the United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR) published in the last 25 years and aims to expand public knowledge on levels of exposure to ionizing radiation and possible associated effects. This publication does not set, or even recommend, radiation safety standards, rather, it provides information on basic science related to radiation (origin, quantities and units), on radiation effects (on humans and the environment) and on radiation sources (natural and artificial). Helping the public understand what radiation is and how it affects life on this planet lies within the core mandate of UNEP.

A selection from the introduction:

Today, we know more about the sources and effects of exposure to radiation than to almost any other hazardous agent, and the scientific community is constantly updating and analysing its knowledge. Most people are aware of the use of radiation in the nuclear power production of electricity or in medical applications. Yet, many other uses of nuclear technologies in industry, agriculture, construction, research and other areas are hardly known at all. To someone who is reading about the topic for the first time, it may come as a surprise that the sources of radiation causing the greatest exposure of the general public are not necessarily those that attract the most attention. In fact, the greatest exposure is caused by natural sources ever present in the environment, and the major contributor to exposure from artificial sources is the use of radiation in medicine worldwide. Moreover, everyday experience such as air travel and living in well-insulated homes in certain parts of the world can substantially increase exposure to radiation.