A report on CERN’s radiological impact
The Swiss and French authorities have just published a report showing that CERN’s radiological impact is negligible.
Since its foundation more than 50 years ago, questions about the Laboratory’s hypothetical radiological impact have been asked repeatedly by the public. These questions are partly due to the name CERN which, for historical reasons, contains the word nuclear. On 16 October, the Swiss and French authorities published a report that takes stock of CERN’s true radiological impact, providing a detailed and documented answer for all those who wonder about the risks of radioactivity.
In their report, the Swiss Office fédéral de la santé publique (OFSP) and the French Institut de radioprotection et de sûreté nucléaire (IRSN), the two bodies responsible for monitoring radiological risks in CERN’s Host States, concluded that CERN’s impact, today and over the past 50 years, has been negligible.
The objective of this report, entitled "Point Zero of CERN" is to provide a reference point prior to the start-up of the LHC. It is based on a programme of independent measurements performed in 2005 and 2006. The two radiation protection bodies commissioned groups of experts who measured the levels of environmental exposure and the concentrations of radionuclides in the air, in water courses, in vegetation and in the soil during 2005 and 2006. The measurements were performed at dozens of points on the CERN site and in the surrounding area.
The results obtained demonstrate that the levels of ionizing radiation and radioactivity measured in these various environments are comparable to those that would be measured without CERN’s impact. The Laboratory’s radiological impact is therefore negligible and significantly below that which can be attributed to natural radioactivity.
In fact, the radioactive dose that can be attributed to the CERN facilities and is received by people living in the area is so low as to be virtually impossible to measure. The estimates show that the dose is around 0.01 milli-Sieverts per year, where the variation that can occur naturally between one geographical region and another can be as much as 20 times larger in the Geneva area. It is equivalent to the dose you would receive flying from Geneva to Athens and back. On average, people living in Switzerland receive nearly 400 times more radiation (3.7 mSv) per year from natural radioactivity, cosmic rays, medical procedures, etc. (see box). It can be concluded that CERN only accounts for a small fraction of a percentage point of background radiation. Studies have also shown that when the LHC comes into operation, the doses attributed to CERN will be similar to those today.
CERN’s low radiological impact is precisely due to the type of research the Laboratory conducts. It is the particles produced by the collisions in the detectors or on the targets of the experiments that are likely to emit radiation and make materials radioactive. However, the radiation is only emitted when the accelerator is operating. The radionuclides produced in the collisions generally have very short half-lives, ranging from a few seconds to five years. Their toxicity is low and their radiological impact well below the limits in force. CERN provides all the protection necessary to minimize the propagation of radiation. The fact that the accelerators, such as the LHC, are buried deep underground provides an additional natural barrier.
CERN complies with the internationally recognised radiation protection system that implies permanent exposure minimization. CERN’s radiological impact thus continues to be negligible and, as a result, well below the regulatory limits. The CERN Safety Commission uses around 200 monitoring stations distributed throughout the CERN sites and in the surrounding area to monitor on-line and in real-time the levels of the ambient radiation exposure and radioactivity in the released air and water. Thousands of analyses on samples of ambient air, water, soil, plant and agricultural products are performed each year and will continue to be performed after the start of LHC operation.
For more information, please go to the CERN and the environment website.
The results of the measurements taken by the various laboratories are available on the OFSP and IRSN websites.
Did you know?
We are constantly exposed to natural radiation from rocks, soil, the sun and space. We also receive doses artificially through medical procedures such as CT scans and x-rays, mining and the remnants of nuclear tests or disasters such as Chernobyl.
Radon, a radioactive gas, is the largest emitter of ionizing radiation. It comes from the minute amounts of uranium that exists naturally in the soil and we breathe it in everyday. Radioactive particles in the soil also lead to trace amounts of radioactivity in the food we eat (“internal exposure”) and naturally occurring radionuclides in the Earth’s crust such as thorium and potassium lead to “terrestrial radioactivity” from rocks. Finally, cosmic rays reaching our planet from the sun, other galaxies and our own, account for 10% of our annual radiation exposure. The atmosphere filters out much of the cosmic rays, so exposure increases with elevation above sea level.
Radiation is usually measured in Sieverts (Sv), which is a measure of the effect of radiation on the body. CERN is estimated to produce 0.01 mSv of effective dose to someone in the local area per year, which is less than 1% of the total annual dose of 3.7mSv that individuals already receive from other sources.
