Radiation Awareness Training

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Radiation Awareness Training
Elayna Mellas Radiation Safety Officer Environment
al Health Safety Manager Clarkson
University Downtown Snell 155 Tel
315-268-6640 emellas_at_clarkson.edu
This training course has been partially
adapted from slides provided by Steve Backurz,
Radiation Safety Officer of The University of New
Hampshire
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Overview

• What is radiation / radioactivity?
• What makes radiation harmful?
• Radiation dose - how much is too much?
• Background radiation your exposure can
• never be zero
• How are you protected at Clarkson?
• Emergencies
• Ordering and receiving radioactive material
• at Clarkson
• Questions?

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• Where Does
• Radioactivity Come From?

• All matter is made up of atoms
• Atoms are the smallest component of an element,
  comprised of three particles
• Protons
• Neutrons
• Electrons
• Protons and neutrons
• are in the central nucleus
• Electrons orbit the nucleus

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What is Radioactivity?

• Definition a collection of unstable atoms that
  undergo spontaneous transformation that result in
  new elements.
• An atom with an unstable nucleus will decay
  until it becomes a stable atom, emitting
  radiation as it decays
• The amount of radioactivity (called activity)
  is given by the number of nuclear decays that
  occur per unit time (decays per minute).

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The Curie

• A unit of activity defined by the number of
  radioactive decays from a gram of radium
• 1 Curie (Ci) 2.22 E12 disintegrations/min (dpm)
  
• Sub-multiples of the Curie millicurie 1 mCi
  2.22 E9 dpm
• microcurie 1 uCi 2.22 E6 dpm
• International units 1 bequerel 1
  disintegration / sec
• Typical activities used at Clarkson University
  are in the ?Ci to mCi range

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Radiation

• Definition energy in the form of particles or
  waves
• Types of radiation
• Ionizing removes electrons from atoms
• Particulate (alphas and betas)
• Waves (gamma and X-rays)
• Non-ionizing (electromagnetic) can't remove
  electrons from atoms
• infrared, visible, microwaves, radar, radio
  waves, lasers

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Electromagnetic Spectrum
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Ionization
Formation of a charged and reactive atom
-
Ejected electron
Beta particle
-
-
-
Colliding coulombic fields
The neutral absorber atom acquires a positive
charge
-
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Why is Radiation Harmful?

• Radiation deposits small amounts of energy, or
  "heat" in matter
• Alters atoms
• Damage to cells DNA causes mutations and cancer
• Similar effects may occur from chemicals
• Much of the resulting damage is from the
  production of ions

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Radiation Dose

• Human dose is measured in rem or millirem
• 1000 mrem 1 rem
• 1 rem poses the same risk for any type of
  ionizing radiation
• internal or external
• alpha, beta, gamma, x-ray, or neutron
• External radiation exposure measured by dosimetry
  
• Internal radiation exposure measured using
  bioassay sample analysis

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Acute Exposure

• Large doses received in a short time period
• accidents
• nuclear war
• cancer therapy
• Short term effects (acute radiation syndrome 150
  to 350 rad whole body)
• Anorexia Nausea
• Fatigue Vomiting
• Epilation Diarrhea
• Hemorrhage Mortality

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Acute Effects of Whole Body Exposure on Man
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Chronic Exposure

• Doses received over long periods
• Background radiation exposure
• Occupational radiation exposure
• 50 rem acute vs 50 rem chronic
• acute no time for cell repair
• chronic time for cell repair
• Average US will receive 20 - 30 rems lifetime
• Long term effects
• Increased risk of cancer, genetic defects
• 0.07 per rem lifetime exposure
• Normal risk 25 (cancer incidence)

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Background Radiation

• Your exposure to radiation can never be zero
  because background radiation is always present
• Natural sources radon gas
• Cosmic rays
• Terrestrial (uranium-235)
• Healing arts diagnostic X-rays,
  radiopharmaceuticals
• Nuclear weapons tests fallout
• Research with radioisotopes
• Consumer products
• Miscellaneous air travel, transportation of
  radioactive material

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Annual Dose from Background Radiation
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Consumer Products

• Tobacco (Po-210)
• Smoke detectors (Am-241)
• Welding rods (Th-222)
• Television (low levels of X-rays)
• watches other luminescent products (tritium or
  radium)
• Gas lantern mantles
• Fiesta ware (Ur-235)
• Jewelry

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Smoke Detectors

• Alpha particles from americium-241 (red lines)
  ionize the air molecules (pink and blue spheres).
  The ions carry a small current between two
  electrodes. Smoke particles (brown spheres)
  attach to ions reducing current and initiate
  alarm.

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Fiesta Ware
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Luminous Watches
Hands and dials contain H-3 or radium that glows
in the dark
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Nuclear Medicine
X-rays and fluoroscopes are used to look inside
the body
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Radioactive Material at Clarkson

• Activities are licensed by the State of New York
• Radiation Safety Committee has responsibility to
  review, approve, and oversee activities
• Radiation Safety Officer (RSO) runs program
• Clarkson is required to
• Train individuals that use sources of radiation
• Train non-radiation workers that work in the
  vicinity of radiation sources
• Monitor and control radiation exposures
• Maintain signs, labels, postings
• Manage and properly dispose of radioactive waste

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Research at Clarkson Using Radiation Sources

• Radioactive materials (both open and sealed
  sources such as S-35, P-32, C-14, H-3, Ra-226,
  Am-241)
• Gas chromatographs (sealed sources)
• Liquid scintillation counters (sealed sources for
  internal standards)
• X-ray diffraction equipment
• Electron microscopes

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Standards for Protection Against Radiation

• Occupational limits
• 5,000 mrem / year TEDE
• 50,000 mrem / year CDE (any single organ)
• 15,000 mrem / year lens of the eye
• Members of public
• 100 mrem / year
• No more than 2 mrem in any one hour in
  unrestricted areas from external sources
• Declared pregnant females (occupational)
• 500 mrem / term (evenly distributed)

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Anticipated Exposures

• Non radioactive workers must receive less than
  100 mrems / year
• Average annual background exposure for U.S.
  population 360 mrem / year
• State and federal exposure limits for radiation
  workers 5000 mrem / year
• Anticipated exposures Less than the minimum
  detectable dose for film badges (likely less than
  10 mrem / month) - essentially zero

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Access Restriction

• Required by license and NY regulations
• Security and control of radioactive material

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Posting of Radiation Areas
All radiation areas are posted with warning
signs Use caution when entering and working in a
radiation area If any container is labeled
radioactive do not disturb
If you have questions or concerns call Craig
Woodworth, radiation safety officer, 268-2391,
Room 147 Science Center
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Emergency Response

• Fire in radioactive areas
• Notify Fire Department and RSO, clear the area of
  people. Remove any seriously wounded persons.
  Keep your distance
• Notify RSO if you suspect
• Inhalation, ingestion or other intake of
  radioactive material
• Accidental release of radioactive material into
  the environment

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Radiation Protection Basics

• Time minimize the time that you are in contact
  with radioactive material to reduce exposure
• Distance keep your distance. If you double the
  distance the exposure rate drops by factor of 4
• Shielding
• Lead, water, or concrete for gamma X-ray
• Thick plastic (lucite) for betas
• Protective clothing protects against
  contamination only - keeps radioactive material
  off skin and clothes

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Radiation Exposure Will Not Make You Radioactive

• Radiation energy in the form of particles and
  waves
• Radioactive material material that is unstable
  and emits radiation
• Contamination radioactive material where it is
  not wanted
• Campfire example burning logs (radioactive
  material), heat (radiation), burning embers that
  escape the controlled area (contamination)

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Shipping Radioactive Materials
Since the atomic energy industry began over 50
years ago, there has been an excellent record of
safety in transportation of nuclear
material Over 4 million packages containing
radioactive material are transported annually
within the US To date, there have been no deaths
or serious injuries
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Ordering Receiptof Radioactive Materials

• Only the RSO is authorized to order radioactive
  material at Clarkson
• When packages are received, call the RSO. He will
  check for contamination, and deliver to the
  package to the lab on the same day as receipt
• All packages containing radioactive materials
  must be secured to prevent theft or loss
• If any package is damaged, do not handle. Call
  the RSO immediately and ask the carrier to stay
  to be checked for contamination

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Labels on Packages of Radioactive Material
Radioactive white I almost no radiation (0.5
mR/hr or 0.005 mSv/hr) maximum on the surface
Radioactive yellow II low radiation levels (50
mR/hr or 0.05 mSv/hr) maximum at 1 meter
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Labels on Packages of Radioactive Material
Radioactive yellow III higher radiation levels
(200 mR/hr or 2 mSv/hr) maximum on surface. 10
mR/hr or .1 mSv/hr maximum at 1 meter.
The transport index is the maximum radiation
level (mR/hr) at 1 meter from the surface of an
undamaged package.
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Your Role in Radiation Protection

• Dont touch or move anything with radioactive
  material labels.
• Report anything that looks out of the ordinary
• If you are uncertain about what to do, where to
  go, requirements, or exposures
• Call the people on the emergency number list
• Call the Radiation Safety Officer (RSO)
• Elayna Mellas
• 268-6640
• Call 911

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Acknowledgements
This training course has been partially
adapted from slides provided by Steve Backurz,
Radiation Safety Officer of The University of
New Hampshire.