MODEL RELEASED. Rural radiation monitoring. Researcher using a radiation detector in a grassy field on the south bank of the Firth of Forth, on the east coast of Scotland. The bridges in the background (upper right) are the Forth Road Bridge and the Forth Rail Bridge. The researcher is monitoring for high levels of radioactivity. Most natural radiation is due to cosmic rays from space, and radon, a radioactive gas produced by the decay of radium from uranium ores. Human sources of radiation include nuclear power stations and pollution from coal-fired power stations. This work is being carried out by the UK's Health Protection Agency.