CURIE was set up in 1987 following the explosion of one of the nuclear reactors at Chernobyl in the former Soviet Union. Soon after that event, high radiation levels were present over the UK, but the nuclear industry delayed warning the public for a week, preventing anyone from taking precautions. To ensure this wouldn't happen again, CURIE decided to take regular readings independent of government or the nuclear industry by purchasing and maintaining its own Geiger counter.
A chart of the North Green readings is shown below. The odd month shows no reading because the meter is regularly sent away for re-calibration. The unit of measurement is the nanosievert per hour which is a measure of the biological impact of radiation on living cells. The Parham readings (averaging 62nSv/hr) are typical of those around East Suffolk (all around 70nSv/hr). The exceptions are readings from close to the nuclear power stations at Sizewell where man-made gamma radiation levels are significantly higher than natural background. Gamma readings outside the station fence at Sizewell can be ten to fifteen times the East Suffolk average depending on how many reactors are operating, but this is still well below a level that could be considered harmful to health.