Frequently Asked Safety Questions
Yes, exposure of people to some types of synchrotron light can cause serious harm. In order to protect staff from the potential hazard, carefully designed safety systems keep people out of dangerous areas when the beam is on. Thick shielding made of concrete and lead keeps the harmful radiation inside those areas. In this way, people are well protected from the very bright synchrotron light.
The types of personal protective equipment used will depend on the type(s) of hazard that may be present during an experiment. For most experiments, personal protective equipment is not required during the actual sample analysis. However, some sample preparation often requires work in an on-site laboratory that may involve various types chemicals and gases. Wearing lab coats, latex gloves, and safety glasses are mandatory while working CLS laboratories. All experiments are reviewed for safety where any special requirements for personal protective equipment are identified.
Yes, material that scientists routinely work with at CLS can be dangerous. Before any research is allowed at CLS, scientists submit a proposal that explains their project. All experiments are reviewed for safety, and must be approved before they are allowed to proceed. The amounts of dangerous material are kept as small as possible, and the risks can be controlled by having clear safety procedures which include identifying all safety requirements.
In the event of a medical emergency, emergency services are notified promptly and will arrive within a few minutes. If the medical team requires access into a controlled area, CLS staff will assist in escorting them to the area. The electron beam would be turned off prior to accessing secure areas therefore no radiation hazard would be present. Other hazards may be present, whether in the lab or in a secure area. CLS staff with access to a secure area are knowledgeable on the hazards that may be present and would assist the emergency services team with safe access to the medical emergency.
No. A carefully designed safety system helps ensure people are out of unsafe areas before the beam can be turned on. This includes a controlled and systematic search of the area within a specified time. The accelerator areas also have locking entry points with specially designed key. This key must be removed from the entry door and placed in a control room keybank, and turned to the operate position, before the electron beam can be turned on. Removing this key from the control room will turn off the beam. Any other means used to open an entry point is detected by sensors and will also turn off the beam.
The synchrotron has been designed to protect workers, scientists, and the public from the radiation produced by the electron beam. A carefully designed safety system helps ensure people are out of unsafe areas before the beam can be turned on. The entry points to the beam areas are locked during operation. Opening an entry point would instantly turn off the beam. Thick concrete and/or lead walls, enhanced with other shielding material in some places, keep harmful radiation away from people when the beam is on. The risk of receiving a radiation exposure from a synchrotron is very low.
The Canadian Light Source creates a very small (about the size of human hair) but powerful electron beam. The beam is kept within a 4” diameter steel pipe, shaped in a ring about 171 m around, to produce synchrotron light. When the electrons in the beam hit other molecules, or when the electron is direction is changed, ionizing radiation is produced. The types of ionizing radiation produced mainly include X-rays, gamma rays, and neutrons. Thick concrete or lead shielding walls surround the ring and keep the harmful radiation away from people when the beam is on. When the beam is off, the radiation is no longer produced.
A dosimeter is device that can measure exposure to ionizing radiation. Some dosimeters are worn by people (personal dosimeter), while other dosimeters are used to help understand radiation levels in certain areas (area dosimeter). Dosimeters can be designed to measure different types of ionizing radiation. At CLS we use personal and area dosimeters to help confirm that staff, scientists, and visitors to the CLS do not receive radiation exposure from the operation of facility.
Staff exposure to ionizing radiation is carefully monitored. A synchrotron facility is required to keep radiation exposures to members of the public (visitors to the facility) below 1 milliSievert per year. CLS staff have never exceeded that limit, and most staff do not receive any radiation exposure due to the operation of the facility.
Meeting the Unexpected
CLS uses both electromagnets and permanent magnets to bend and focus the beam, and to make synchrotron light. The magnetic field may be a few Tesla, but is mostly contained within the magnet structure. Strong magnetic fields may create a potential pinch point hazard within a few inches of the permanent magnets. The attractive force on a metal object near a permanent magnet may be so strong that the object is pulled from the worker. This attraction may happen very quickly and create a pinch point when the object attaches to the magnet, especially if the worker doesn’t let go of the object. All magnets are posted with warning signs to indicate when a magnetic field hazard may be present.
A search and secure process is designed to make sure no one is inside the rings before the electron beam is turned on. As the rings are large areas, they have been divided into sections. As each section of the ring is searched, cleared of personnel, and secured, a flashing light turns on to indicate the electron beam will be turned on soon. Each section has a unique key for the entry point. The entry keys must be taken to the control room, inserted into a key bank, and turned to the operate position. A horn will sound in the rings for an additional minute before the operator is able start the electron beam. At any time, someone inside the ring can push an emergency button that will shut-off or prevent turning on the electron beam, and then exit the rings.
If a person was inside the rings when the electron beam is on, they would receive a radiation exposure. The severity of the radiation dose would depend greatly on the operational details and their precise location. The radiation exposure would likely be very serious, and could be fatal depending on the duration of the exposure.
No. Chernobyl was a nuclear power generating station. A nuclear power plant requires fuel, usually uranium. A nuclear reaction results in splitting uranium atoms, which generates a lot of heat, and a lot of ionizing radiation. When under control, heat generated is used to create steam, which in turn produces electricity by driving a steam turbine. The ionizing radiation is contained by the design of the facility. At Chernobyl, a combination of a safety test gone wrong and poor design lead to an accident where nuclear fuel overheated resulting in an intense fire that damaged the power plant. Once the structure was compromised, the ionizing radiation could no longer be contained by the facility design. The result was a release of 50 GBq in a radioactive cloud that spread across Europe and around the world.
The CLS is an accelerator facility. There is no nuclear fuel. CLS uses electricity to create a beam of electrons which, when circulated in our storage ring, produce high quality synchrotron light. In a synchrotron facility, the beam can be quickly stopped by turning off the power supply. When the electron beam is off, there is no radiation hazard.
It takes a lot of electricity to keep the electron beam on. In the event of a sudden power outage, the beam automatically shuts off. The CLS is equipped with an emergency generator to supply back-up power to lighting and other essential services. The back-up power generator does not produce enough electricity to keep the beam on.
No! A problem with the electron beam will not cause an explosion. The electron beam requires very precise control of electricity to make the beam circulate in the 171 meter circumference storage ring. If anything goes wrong, the beam quickly stops circulating. Any radiation created when the beam is stopped is contained within the thick shielding walls designed to keep the harmful radiation away from people. The design of the facility also allows us to shut off the beam any time.
Accidents where the injury results in time away from work are very infrequent at CLS. Between 2005 (when normal operations started) and 2019, there have been 10 injuries where the injured worker could not immediately return to work. Other more minor types of accidents, such as minor cuts or slips/trips/falls, strains, and pinches occur more frequently and, when combined with reporting of all safety incidents, helps CLS keep its injury rate very low.
If a person were to be in the direct path of the electron beam it would likely be fatal. Although the beam size is very small, the high energy of the beam would destroy any cells impacted. In addition, the scattered radiation produced when the beam strikes your body, or any other molecules such as those in air, magnets or the beampipe for example, would lead to a large radiation dose to the person.