Dalhousie University Radiation Safety Office

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Dalhousie UniversityRadiation Safety Office

• 2004 Refresher Training

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Principal Investigator Responsibilities

• It is the responsibility of the Principal
  Investigator to ensure that all workers in their
  research group who will be handling radioactive
  materials are registered with the Radiation
  Safety Office and have completed the required
  Radiation Safety Training.
• Workers within the research group who will not be
  handling radioactive materials must, however,
  receive some instruction relating to the
  radiation hazards.

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Canadian Regulations

• The Canadian Nuclear Safety Commission regulates
  the use of nuclear energy and materials to
  protect health, safety and the environment and to
  respect Canadas international commitments on the
  peaceful use of nuclear energy. The Nuclear
  Safety Control Act can be viewed on the CNSC
  web site at http//www.cnsc-ccsn.gc.ca/eng/license
  es/regulations

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Radiation Safety ProgramOrganizational Structure
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Radiation Safety Committee

• Dr. John Andrew NSCC
• Dr. A. Chatt SLOWPOKE
• Dr. M. Dobson Chair, Biochemistry
• Dr. R. Dunlap Physics
• Dr. D. Godfrey-Smith Earth Sciences
• P. Jones Secretary/RSO
• Dr. W. Louch Director, EHS
• Dr. R. McLeod Biochemistry
• Kay Murphy - Pharmacology
• Dr. A. Stadnyk - Pediatrics

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Instructions

• Refresher training is intended for those
  radioisotope workers who have previously attended
  the Radiation Safety Training course prior to May
  of 2002. The refresher training module is not
  intended to substitute for the full day training
  session required of all new or previously
  untrained workers. Refresher training must be
  documented by submitting the required form and
  quiz found in the Forms section of the EHS web
  site at http//www.dal.ca/ehs

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Worker Obligations

• Use equipment, facilities, protective clothing
  and devices in a responsible and reasonable
  manner
• Comply with all permit conditions
• Report any situation which is unsafe
• Report potential security risks
• Obey all notices and warning signs
• Take all precautions necessary to ensure your
  safety and the safety of others in your work area.

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Classifications of Workers

• Nuclear Energy Worker (NEW)

• A Person Who Is Not A Nuclear Energy Worker

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Dalhousie Rad Workers

• Radiation workers at Dalhousie are normally
  considered to be persons working in controlled
  areas for whom maximum permissible dose limits
  apply as they do for A Person Who Is Not A
  Nuclear Energy Worker. The majority of workers
  at Dalhousie receive radiation doses far below
  regulatory limits as set by the CNSC.
• Allowable annual whole body dose 1 mSv
• Average annual whole body dose 0.2 mSv

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A Review of the Hazards

• External exposure
• Internal exposure
• Spread of contamination

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External Exposure

• A nuclear substance present in the work area is
  outside the body and thus constitutes a potential
  external exposure hazard

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Internal Exposure

• The nuclear substance becomes an internal hazard
  if inadvertently deposited into the body

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Common Routes Of Entry

• Ingestion food or drink consumption in lab,
  poor personal hygiene (hand washing)
• Inhalation use of volatile materials, scraping
  TLC plates on open bench, heating solutions
  outside fume hood etc.
• Absorption uncovered cuts or abrasions, exposed
  intact skin, eyes

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Spread of Contamination

• Contributing factors are poor housekeeping and
  poor personal hygiene (hand washing). Long hair
  should be tied back.

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Workplace Laboratory Procedures

• Careful planning
• Safe work habits
• Routine monitoring record keeping
• Proper disposal of radioactive waste
• 5. Consultation with Radiation Safety

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Careful Planning

• Know the hazards associated with the nuclear
  substance you will be using.
• Is your lab approved for the nuclear substance
  you wish to use ?
• Do you have the correct personal monitors, survey
  equipment and shielding
• 4. Restrict operations to a designated area
  within the lab.

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Safe Work Habits

• As Low As Reasonably
• Achievable
• Strive to work in such a manner as to maintain
  the least amount of exposure to ionizing radiation

ALARA
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Radiation Safety Principles To maintain doses
ALARA
TIME
DISTANCE
SHIELDING
CLEANLINESS
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TIME

• Accumulated time from external radiation exposure
  is directly proportional to the amount of time
  spent in the area

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DISTANCE

• The radiation field is inversely proportional to
  the square of the distance from the source

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SHIELDING

• The amount of shielding required depends on the
  type of radiation, the activity present and the
  dose rate acceptable outside the shielding
  material
• lt 2.5 uSv/hr

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CLEANLINESS

• Maintain good housekeeping practices
• Maintain good personal hygiene (hand washing)

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Summary of Radiation Protection Principles

• Time work efficiently to reduce the actual time
  of exposure
• Distance maintain adequate distance from the
  source (this may be as simple as transporting
  tubes in racks as opposed to carrying them in
  your hand)
• Shielding incorporate appropriate shielding as
  required to reduce exposures to a minimum ( e.g.
  plexiglass for beta emitters or lead for gamma
  emitters.
• Cleanliness maintain a clean lab and always
  remove gloves and wash hands before leaving the
  laboratory

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Routine Monitoring Recordkeeping

• Maintain records of use/non-use periods
• Wipe test weekly during periods of use
• Direct monitor daily for P-32 use

• Maintain accurate inventory of all stock from
  cradle to grave
• Maintain required contamination survey results

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Direct Monitoring

• Advantages
• Immediate indication of contamination
• Able to monitor large and irregular surfaces
  efficiently
• Disadvantages
• Cannot indicate whether the contamination is
  loose or fixed
• Cannot be used in high bkg. areas
• Cannot detect low energy beta emitters such as
  H-3, the detection efficiency for C-14, S-35 and
  P-33 is less than 10.

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Direct Monitoring Technique

• Hold the probe as close to the surface being
  monitored without actually touching the surface
• Move the probe slowly in an S shaped motion

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Indirect Monitoring Wipe Test

• Advantages
• Able to distinguish between loose and fixed
  contamination
• Can be performed in high background areas
• Can detect low energy beta emitters
• Can identify the contaminant
• Disadvantages
• Results are not immediate
• Procedure is time consuming

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Indirect Monitoring Technique

• Prepare a floor plan of the lab.
• Identify locations to be tested.
• Using a Q-Tip or filter paper moistened with a
  suitable solvent wipe a representative area. ONE
  WIPE/LOCATION
• Prepare a background control using a clean wipe.
• Allow wipes to air dry.
• Place dried wipe in counting vial and add
  appropriate cocktail.
• Mark cap with correct wipe identification.
• Count using an appropriate counting window for
  the isotope for which you are surveying.
• Record results in Radiation Safety Records
  logbook.

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Management of Radioactive Waste

• Categories of Radioactive Waste
• Dry dry solids, dehydrated biological
  materials, paper, glassware, gloves, apparel
• Liquid aqueous and non-aqueous
• Biological animal carcasses, bedding, solid
  excreta, tissue, organs, blood, etc..
• Sharps broken glass, needles, blades, scalpels,
  etc..

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Disposal and Packaging Procedures

• Dry ( Solid) Waste
• Package all solid waste in designated boxes lined
  with orange garbage bags.
• Segregate waste by radionuclide.
• Arrange with RSO for delivery to waste storage
  room for decay. All radionuclides with a half
  life of lt 90 days are held for a minimum of ten
  half lives before transport as biomedical waste
  for incineration.
• Consult with RSO for disposal of radionuclides
  with a half life of gt 90 days.

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Disposal and Packaging Procedures (continued)

• Storage Times For Dry (solid) Waste
• P-33 254 days
• P-32 140 days
• S-35 870 days
• I-125 600 days
• Cr-51 280 days
• Prior to disposal as biomedical waste for
  incineration package must first be monitored to
  ensure no counts in excess of two times the
  background count are detectable by the direct
  monitoring technique

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Disposal and Packaging Procedures (continued)

• Aqueous Liquid Waste
• Aqueous waste should be disposed of through a
  designated laboratory sink that is used
  exclusively for the disposal of rad waste. Waste
  should be followed by copious amounts of water to
  ensure flushing of the immediate system.
• For high level aqueous waste please contact the
  RSO for advice.

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Disposal and Packaging Procedures (continued)

• Non- aqueous Liquid Waste
• LS cocktail need not be drained from the counting
  vials.
• Place intact vials in a plastic bag lined
  cardboard box.
• Label box lab of origin, radioisotope, solvent,
  estimated activity
• Waste should be transported to a designated area
  on the first Tuesday of each month for pick up by
  EHS.
• Boxes containing materials other than the
  counting vials will be returned to the lab of
  origin for repackaging.

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Disposal and Packaging Procedures (continued)

• Biological Waste
• Arrangements for disposal should be made through
  the Radiation Safety Office. As all biological
  waste must be shipped for incinerations
  provisions must be made for refrigerator or
  freezer storage until arrangements can be made
  for shipment.

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Disposal and Packaging Procedures (continued)

• Sharps
• Sharps must be packaged in an appropriate sharps
  container for ultimate pick-up and subsequent
  shipment for incineration.

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Consultation with Radiation Safety

• The Radiation Safety Officer for Dalhousie
  University is Pauline Jones.
• She can be reached
• Telephone [phone]
• Fax [phone]
• E-mail pauline.jones_at_dal.ca
• Visit the EHS web site at http//www.dal.ca/ehs