It is understandable that people have questions about the safety of nuclear science and the laboratories — like NSCL — and other facilities where it is studied or applied. Here are some frequently asked questions and answers about safety at NSCL and MSU.
Radiation occurs when the unstable elements that surround us evolve to become stable, part of a natural process that occurs continuously in the world. Radiation also is a result of particles from space interacting with our atmosphere. Radiation is the emission of energy in those processes.
Radiation, in itself, is not dangerous. We are bombarded by radiation daily from the sun and from the cosmos. It can be found in the potassium of a banana and in the soil in our backyard. The key is how much radiation. It’s like salt: eating a small quantity of salt is not harmful, but eating several pounds of salt would make you very sick. Our bodies weather small doses of radiation well. In fact, radiation is a part of how we live.
Because there were larger quantities of radioactive materials in the Earth thousands and millions of years ago, our ancestors received higher doses than we do now. However, even now in some parts of the world — in Kerala, India, for example — people receive up to 10 to 30 times the dose we receive in Michigan from radiation from soil and rocks.
Too much radiation, however, is harmful. It can strip electrons from the atoms that make up the living tissue in our bodies, resulting in tissue damage and, under some circumstances, the development of cancer. Like salt, very large quantities of radiation will cause serious illness or even death.
The difference is that we can taste salt and would not eat a large quantity voluntarily, but we cannot taste, smell, feel, or see radiation. Our bodies cannot warn us if they get too much radiation. This is why it’s important to understand and monitor radiation. Fortunately, there are instruments that can detect radiation long before it reaches harmful levels.
Rare isotopes are variations of an element that occurs in nature. They’re called rare because they don’t exist long in nature — sometimes much less than the blink of an eye. At the center of an atom is the nucleus, made up of particles called protons and neutrons. The number of protons determines the element. For example, all oxygen nuclei have exactly eight protons and all calcium nuclei have exactly 20 protons. The different isotopes of a given element have different numbers of neutrons in their atomic nuclei. For example, the most common isotope of oxygen, oxygen-16, has eight protons and eight neutrons. The number of protons and neutrons combined gives the isotope number. Very few isotopes are stable. When an isotope has too few or too many neutrons (when compared to a stable one), it will be unstable and eventually decay by emitting radiation. These isotopes are called radioactive.
Many radioactive isotopes occur in nature, and some may be found in our bodies — from what we eat, drink, and breathe. For example, the isotope carbon-14 is radioactive: it has six protons and eight neutrons and is found in all living organisms, including our own bodies.
Some radioactive isotopes provide major medical benefits through diagnosis or treatment of diseases. Others have important applications, such as in biological sciences, environmental sciences, archeology, national security, and energy generation.
Short-lived isotopes cannot be found naturally on Earth — they have long decayed since our planet was formed billions of years ago. Thousands of short-lived isotopes are continually created in the cosmos — in supernovae, for example. They play a crucial role in the ongoing creation of the elements in the cosmos as they did in the creation of the elements in our solar system billions of years ago.
Because the rare isotopes live for such a short time the only way we can study them is to create them in a laboratory, for example, with an accelerator. An accelerator hurls an intense beam of atomic nuclei against other nuclei contained in a block or foil of material called the target. As a beam nuclei collides with target nuclei, they throw off radiation, including many different combinations of protons and neutrons, thus forming new nuclei. Rare isotopes once seen in the cosmos are recreated for a fleeting moment in a controlled setting. They are separated and then can be studied. At a modern accelerator laboratory like NSCL, one may study rare isotopes that live for only one-millionth of a blink of an eye.
Unlike nuclear reactors, which store significant amounts of radioactive material, accelerator laboratories like NSCL create radioactive rare isotopes in high-energy beams and in tiny amounts. The production of radioactivity by an accelerator can be easily controlled. The accelerator can be shut off quickly, like turning off a lamp.
The amount of radioactive material actually stored at accelerators like NSCL is comparable to radioactive material kept on site at medical facilities that provide diagnostic tests.
Radiation isn’t an issue outside the active accelerator. We are surrounded by low doses of radioactivity every day — from bricks in a building to the water we drink and some foods we eat: nuts, cereals, milk, vegetables, meats, fruit, and even chocolate.
The radiation produced when the accelerator is on is shielded from humans by thick concrete walls. When the accelerator is turned off, the radiation dies away quickly. It is safe to visit the building, work in the building, or be a neighbor to a cyclotron. Lab employees typically do not need to wear special protective clothing in the facility.
An accelerator laboratory is like any other laboratory or industrial site. Much care goes into the design to prevent accidents or other unusual situations. Many instruments placed around the laboratory monitor the radiation produced. If the levels become too high, the accelerator will be shut off.
At NSCL, we receive more than 2,000 visitors a year. We monitor their safety closely. The following organizations all have a hand in monitoring the safety of our lab and its workers.
Most accidents at accelerator laboratories stem from industrial hazards, like using ladders, electricity, and cutting tools, and working with sharp pieces of metal.
Yes. For many years, NSCL has been open for tours for the public. In fact, school children are frequent and enthusiastic visitors. Visitors can see many of the experimental devices, some of the specialized accelerators, and staff and scientists at work. Some areas, such as the targets at which the high intensity beams are fired, are not part of public areas to maintain safety and security.
What about the information generated at the lab?
No classified research is done at NSCL. Research is presented at public meetings and published in easily available journals.
We welcome your questions. Please e-mail Ask NSCL or phone us at 517-333-6337.