Office of Risk Management UNIVERSITY OF OTTAWA Office of Risk Management ANALYTICAL X-RAY SAFETY ONLINE USER TRAINING This training is intended for users of X-ray devices equipped with an interlock system

IMPORTANT FACTORS The X-ray device that you are/will be using must be registered with the Office of Risk Management (ORM) to ensure that potential exposure controls are in place and have not been compromised The X-ray device must also be registered with the Ministry of Labour (MOL), ORM can inform you if this has been done If you will be using an open X-ray beam device, a more comprehensive training is mandatory. Please contact ORM for assistance UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

TRAINING OBJECTIVES Creating and maintaining a safe work environment Developing proper work procedures, habits and attitudes UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

TRAINING OUTLINE Legislation Sources and Use of X-rays Biological & Health Effects X-ray safety in the lab Exposure SOPS Security Emergencies Summary References UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

LEGISLATION UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Analytical X-ray Safety Training – User Training LEGISLATION Federal Guidelines Health Canada Safety Code 32: Safety Requirements & Guidance for Analytical X-ray Equipment (outlines responsibilities of owners of equipment, safety procedures, standards, surveillance and monitoring) Radiation Emitting Devices Regulations (C.R.C., c. 1370): regulate the interpretation, standards of design and construction and standards of functionning of radiation emitting devices UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

LEGISLATION Ontario Ministry of Labour Operates in accordance with the Ontario Occupational Health and Safety Act. sets standards establishes regulations for: Possession, safe use of X-ray equipment for non medical uses MOL jurisdiction for X-ray > 0.115 mR/h or 1 uG/h CNSC licences high energy x-rays ? 10 MeV UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

TRAINING OUTLINE Legislation Sources and Use of X-rays Biological & Health Effects X-ray safety in the lab Exposure SOPS Security Emergencies Summary References UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Outline How are X-rays produced SOURCES AND USES Outline How are X-rays produced Atomic properties and interaction with matter X-ray machine vs X-ray source What you can find at Ottawa U Get to atomic level UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

What Are X-rays? X-rays are part of electromagnetic spectrum (energy range of 10eV – 120KeV) type of ionizing radiation (made of photons) originating from the electron shell May be produced by machines UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

How Are X-rays Produced? X-rays can be produced by a variety of phenomena. When high-energy X-rays, gamma-rays or electrons bombard materials, the excited atom within emit characteristic fluorescent X-rays. Alternatively, whenever charged particles pass within certain distances of each other without being in fixed orbits, the accelerations can give off X-rays Examples of X-ray production: Bremsstrahlung (see next page), Ionization, X-ray tube, tesla coil, synchrotron radiation, cyclotron radiation, photoelectric effect, compton scattering, pair production X-ray production whenever electrons of high energy strike a heavy metal target, like tungsten or copper. When electrons hit this material, some of the electrons will approach the nucleus of the metal atoms where they are deflected because of there opposite charges (electrons are negative and the nucleus is positive, so the electrons are attracted to the nucleus). This deflection causes the energy of the electron to decrease, and this decrease in energy then results in forming an x-ray. Medical x-ray machines in hospitals use the same principle as the Crooke’s Tube to produce x-rays. The most common x-ray machines use tungsten as there cathode, and have very precise electronics so the amount and energy of the x-ray produced is optimum for making images of bones and tissues in the body. UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

X-ray Production - Bremsstrahlung Electron (-) X-rays can be produced from acceleration of electrons which are deflected from their original paths by other charged particles such as the nucleus X-Ray Target Nucleus Tungsten UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

X-ray devices X-rays produced whenever a high voltage, a vacuum and a source of electrons present Most x-ray devices emit electrons from a cathode, accelerate them with a voltage and hit the anode (target) that emits X-ray X-ray production whenever electrons of high energy strike a heavy metal target, like tungsten or copper. When electrons hit this material, some of the electrons will approach the nucleus of the metal atoms where they are deflected because of there opposite charges (electrons are negative and the nucleus is positive, so the electrons are attracted to the nucleus). This deflection causes the energy of the electron to decrease, and this decrease in energy then results in forming an x-ray. Medical x-ray machines in hospitals use the same principle as the Crooke’s Tube to produce x-rays. The most common x-ray machines use tungsten as there cathode, and have very precise electronics so the amount and energy of the x-ray produced is optimum for making images of bones and tissues in the body. UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Anode (+) Cathode (-) X-Rays X-ray Tube UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

X-ray machine X-ray source SOURCES AND USES X-ray machine electrically powered device with a PRIMARY purpose of producing X-rays analyzes structures or materials X-ray source any part of a device that emits X-rays, whether or not the device is an X-ray machine, e.g.: electron microscope UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

X-ray Diffraction (XRD) SOURCE AND USES The University of Ottawa holds two types of X-ray instruments used for academic research X-ray Diffraction (XRD) commonly used in structural analysis powder and single-crystal diffractometers are available X-ray Fluorescence (XRF) observes fluorescent emissions of x-ray and UV as atoms hit by x-rays commonly used to study earth materials UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

TRAINING OUTLINE Legislation Sources and Use of X-rays Biological & Health Effects X-ray safety in the lab Exposure SOPS Security Emergencies Summary References UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

BIOLOGICAL & HEALTH EFFECTS Factors determining biological effects Dose and equivalent dose Total dose and dose rate Energy of radiation Amount of body exposed Cell and individual sensitivity UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Dose (D) Effects from radiation depend on amount of radiation received (absorbed) by the body Called Dose or Absorbed Dose (D) quantity of energy deposited in a unit of mass of material Units of Measure: Gray (Gy) or rad 1 Gy = 100 rad UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Equivalent Dose (H) Biological effect caused by radiation being deposited in human body Dependant on type of radiation and energy Quality factor (QF) used to relate the absorbed dose of various kinds of radiation to the biological damage caused to the exposed tissue since different kinds of radiation cause different degrees of damage. The higher the quality factor, the greater biological risk or greater effect than the radiation with a lower quality factor (for the same absorbed dose) UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Factors determining biological effects TOTAL DOSE Effects from acute doses (> 1 Sv = 100 rem) easily observed < effects on chronic dose at 0.1Sv effects not reliably quantifiable due to no observable effects UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Factors determining biological effects DOSE RATE Dependent on amount of radiation over period of time (exposure) Acute (large) vs chronic (small) If amount of radiation same, acute dose more damaging, since tissues does not have time for repairs UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Factors Determining Biological Effects ENERGY OF RADIATION X- rays have wide range of energies (10 to100 KeV) Higher the energy deeper the penetration into tissue Lower energy x-ray absorbed first layers of skin (shallow dose) UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Factors Determining Biological Effects AMOUNT OF BODY EXPOSED Harder and more damaging for body to recover from dose to large area of body than a small, localized area such as hand Might include sensitive organs UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Factors Determining Biological Effects SENSITIVITY Individual sensitivity to absorbed radiation Type of cells: some more radiosensitive such as those undergoing cell division UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

No genetic effects observed in humans only in animal studies Biological effect inherited by children resulting from a modification of genetic material in a parent No genetic effects observed in humans only in animal studies No statistically significant genetic effects observed in children in Japanese atomic bomb survivors (any effects on offspring from nuclear bombing survivors in Japan in WW2 from women already pregnant) UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Somatic Effects Biological effect observed in our lifetime to exposed individual (not carried to offspring) At doses 5 Sv (=5000 mSv), skin begins to show “sunburn” (MOL annual limit = 50 mSv) Eye damage (cataracts) can results at doses > 6 Sv (=6000 mSv) (MOL annual limit = 150 mSv) UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Risk of Cancer Radiation exposure including exposure to x-rays does not cause any unique forms of cancer that are not normally observed in humans What we know about radiation caused cancers is a result of the accidental or nuclear weapon related exposure of people. Many people who worked with radiation before we were aware of its hazardous nature received high exposures that caused some later cancers. For example, about 1700 women were employed in the United States during the 1920's to paint radium paste on the dials and numerals of clocks and watches to make them luminous. They used their tongues to tip the brushes to a fine point and ingested radium in the process. Their average bone dose was 17,000,000 mrem. For comparison, natural and medical sources (diagnostic) cause an average yearly exposure to a person in the United States of about 200 mrem to the whole body. A dose as high as 17,000,000 mrem could cause immediate death if delivered to the whole body over a short time. These women did not experience early effects because this dose was not to the whole body and was protracted over many years. Forty-eight of these women died of bone cancer, compared to the zero or one death due to bone cancer that would normally be expected in 1700 people. Early uranium mine workers were exposed to high levels of airborne radioactivity. Among 4100 U.S. miners studied, the average lung dose was 4,700,000 mrem. One hundred thirty‑five lung cancer deaths had been observed up to 1972 compared to an expected incidence of about sixteen. Radiation therapy has caused cancers in medical patients. For example, there were 15,000 British patients treated with x rays for arthritis of the spine (ankylosing spondylitis) with average doses of 370,000 mrem. About 115 extra cancers occurred in this group of 15,000 because of their exposure. Among survivors of the atomic bomb attacks on Japan, a group of 24,000 people have been studied who received an average dose of 130,000 mrem. Up until 1972 about 120 extra cancers had resulted. No extra genetic effects in their offspring have been proven. This fact is an important contribution to our "knowledge base" for the genetic effects from radiation. It is surprising that even with doses as high as these listed here only a small fraction of these people died of radiation related diseases. To determine from this kind of information what the chance any one person has of dying of cancer from a low dose of radiation is impossible. We can, however, determine a reasonable average. This estimate is obtained by extrapolating the data at high doses down to low doses of radiation. The actual number obtained depends more on how the extrapolation is done than on the actual data used for this purpose. Different methods of extrapolation will result in different estimates of cancer risk. This is why the experts don't always agree on how carcinogenic radiation is and this is the source of much controversy. The best way to describe this estimate is to say how many cancer deaths would be added if a large group of people received a particular dose. The number accepted by most experts is shown here. If 10,000 people each received 1,000 mrem, then we would expect one extra cancer death over the lifetime of this entire group because of this radiation. For comparison, we would normally expect about 1,640 cancer deaths in this group. You can see why it's difficult to prove that low doses of radiation cause cancer. The 1,640 "normal" cancer deaths is an average. The actual number can be quite different, larger or smaller. To prove that radiation is the cause, the dose has to be high enough to add more cancer deaths than this natural fluctuation. Otherwise it gets drowned out statistically and we can't say that radiation caused these cancers. UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Health Effects of X-rays Due to localized nature of X-ray beams, acute doses to whole body NOT USUAL Most health effects occur due to chronic exposure (hospital, dentist) Most exposure to analytical X-rays results in exposure to skin and extremities UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Doses limits imposed by Ministry of Labor (designated X-ray worker) Worker Protection: Occupational Dose Limits (designated X-ray worker) 50 mSv annually whole body 50 mSv annually – to any organ, skin, or extremity 150 mSv annually – eye dose equivalent < 5 mSv during pregnancy General Public: 5 mSv annually (whole body) UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

TRAINING OUTLINE Legislation Sources and Use of X-rays Biological & Health Effects X-ray safety in the lab Exposure SOPS Security Emergencies Summary References UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

X-RAY SAFETY IN THE LAB Control of Exposure ALARA = As Low As is Reasonably Achievable The ALARA Principle is a philosophy of radiation safety that every reasonable effort should be made to minimize dose. This guiding philosophy has actually been incorporated in regulations for all entities that possess radioactive material. The ALARA provision in regulations facilitates proactive measures for radiation protection and safety. The ALARA principle is defined as “making every reasonable effort to maintain exposures to radiation and releases of radioactive material in effluents as low as is reasonably achievable, taking into account the state of technology, the economics of improvements in relation to benefits to the public health and safety and other societal and socioeconomic considerations, and in relation to utilization of ionizing radiation in the public interest”. UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

X-RAY SAFETY IN THE LAB Radiation Protection Basics AMOUNT & TYPE OF RADIATION EXPOSURE TIME DISTANCE SHIELDING UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

X-RAY SAFETY IN THE LAB Radiation Protection Basics Exposure to X-ray radiation is reduced if: TIME exposed to source is decreased DISTANCE from source is increased SHIELDING from source is increased UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

X-RAY SAFETY IN THE LAB Comparisons on shielding requirements for X-rays Paper Plastic Lead Concrete  Alpha  Beta 00 g Gamma and X-rays 10 n Neutron UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

X-RAY SAFETY IN THE LAB Radiation Protection Basics How do I apply the ALARA principle in my lab ? Be aware of potential X-ray hazards, exposure levels and safety controls Be aware of operating and emergency procedures Be aware of practice that does not follow the ALARA principle Report incident or unsafe working conditions to your supervisor and ORM UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

X-RAY SAFETY IN THE LAB Radiation Protection Basics Am I at risk of a X-ray exposure? The engineering controls, such as interlocks and lead shielded doors, on the X-ray instruments used at Ottawa U prevent the user from being exposed to the X-ray beam ORM carries out leak testing every year on each registered instrument Consequently, no further exposure control is necessary for the user. HOWEVER … UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

X-RAY SAFETY IN THE LAB Radiation Protection Basics Am I at risk of a X-ray exposure? However, should the engineering controls in place be overridden or additional work be carried out, besides the standard procedures recommended by the manufacturer, involving tasks such as Beam alignment Change of X-ray tube General maintenance YOU MUST CONTACT ORM FOR FURTHER ASSISTANCE. ADDITIONAL CONTROL MEASURES, SUCH AS THE USE OF PERSONAL DOSIMETER, MAY BE REQUIRED. UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Control of Exposure DOSIMETRY Devices monitor and record ionizing radiation doses (occupational exposure) Must distinguish from background radiation UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Control of Exposure – TLD Badges record cumulative whole body dose (mSv) prevent over-exposure worn at the chest or waist levels Each badge is assigned to a specific individual and cannot be shared by others worn only at work and not taken off campus UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Leak Test Annual leak test recommended or after equipment has been moved or modified. Dose rate must not exceed 1 microGray/h from any accessible external surface Contact X-ray compliance safety specialist to arrange test By Ontario Health and Safety Act, 28.1.c – you must report to your employer/supervisor the absence or defect in any equipment or protective device of which you are aware of and which may endanger yourself or others UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Non-beam Hazards The following include hazards that are not directly associated with the X-ray beam: Electrical Hazards: X-ray generator = high DC power supply that operates around 40-50 kV + may contain large capacitors that can store sufficient power to possibly kill a person even when turned off. They should only be handled by trained qualified personel. Cryogenics: in the presence of cooling systems, cryogenic fluids such as helium, nitrogen or hydrogen, can cause frostbite upon eye or skin contact Chemicals: could be toxic, corrosive, flammable. Appropriate or additional safety precaution may be required when use with X-ray equipment UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Signs & Labels X-ray warning signs or devices posted in visible location on equipment & door ENERGIZED EQUIPMENT UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

SOPs for Equipment Standard operating procedures are required to be developed by Supervisor for each individual X-ray device: used under guidance and supervision of Authorized User beam shall be directed toward an unoccupied area (eg. wall) limit dimensions of beam adequate shielding energized equipment never unattended in unlocked area no repairs or sample adjustment when equipment energized UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Security Only authorized users may have access to X-ray devices Energized equipment must be attended at all times Lock lab door when equipment not attended UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Emergencies Report any incidents of excessive exposure or theft to X-ray compliance safety specialist After hours call Protection Services at 5499 or Emergency at 5411 If safe to do, de-energized equipment by turning power supply Prevent further access by locking lab door UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

Summary – Please remember Make sure your X-ray instrument is registered with ORM and MOL Register with ORM as a user and complete the online training and the knowledge quiz Respect and follow the ALARA principle Be aware of: X-ray hazards, non-beam hazards, SOPs, emergency procedures and malpractices Be compliant: report incidents/accidents, unsafe working conditions, wear dosimeter if required UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

TRAINING OUTLINE Legislation Sources and Use of X-rays Biological & Health Effects X-ray safety in the lab Exposure SOPS Security Emergencies Summary References UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT

REFERENCES University of Ottawa X-ray safety program www.uottawa.ca/services/ehss/x-ray-safety-prgm.html Ryerson University X-ray safety training www.ryerson.ca/cehsm/training/index.html#xray Ontario Ministry of Labour O. Reg 861 www.e.laws.gov.on.ca/DBLaws/Regs/English/900861_e.htm Health Canada Safety Requirements and Guidance for Analytical X-ray Equipment (Safety Code 32) www.hc-sc.ca/hecs-secs/ccrpb/publication/94ejd186/print.htm National Atomic Museum (New Mexico) www.atomicmuseum.com Health Physics Historical Instrumentation Collection Museum www.orau.org/ptp/museumdirectory.htm UNIVERSITY OF OTTAWA - OFFICE OF RISK MANAGEMENT