Annual Refresher Radiation Safety Training

For VTH Staff and Students

Washington State UniversityRadiation Safety Office

In each laboratory that is authorized for radioactive materials use, you will find this form (RHF-3) posted.

This form gives the contact information for the Washington state Department of Health. It also list some of your and some of the employer's responsibilities.

The University Policy for the Use of Radiation is:

ALARA(As Low As Reasonably Achievable)

It is also a regulatory requirement!

This is the radiation safety principle that requires the use of all reasonable methods to minimize radiation dose to workers and prevent the release of radioactive materials to the environment.

What are the radiation hazards present at the VTH ?

Diagnostic Imaging = Radiography/Fluoroscopy + Nuclear Imaging(kilovoltage x-rays) (Tc-99m, a radionuclide)

Radiotherapy = Linear Accelerator (LINAC) + Ophthalmic application (Megavoltage x-rays + electrons) (Sr-90 sealed source)

Radiopharmaceutical patient treatments = Radioiodine (I-131)

Dental radiography = Treatment room and mobile (kilovoltage x-rays)

Orthopedic research lab = Densitometry (low kilovoltage x-ray)

Intra-operative Radiography + Fluoroscopy (kilovoltage x-rays)

Stall-side and Field Radiography = (kilovoltage x-rays, mobile and portable)

Who are the “Authorized Users”who are supervisory over these sources of radiation ?

Dr. Greg Roberts – Diagnostic ImagingDr. Janean Fidel - RadiotherapyDr. Rance Sellon – Radiation OncologyDr. Raelyn Farnsworth – Dental labDr. Steve Martinez – Orthopedic labDr. Pamela Lee – Cardiology + SA Surgery

Graduate DVM’s employed by the CVM

Authorization to Image or Treat a Veterinary Patient Using Radiation at the VTH

The procedure must be ordered (prescribed) by one of the listed Authorized Users or a graduate veterinarian employed by the VTH, taking into consideration the Risk/Benefit of the procedure.

Veterinary equipment and radiopharmaceuticals intended for veterinary use must not be used on a human. No source of radiation held under the authority of the University is licensed for use on or in a human.

A Veterinary patient that has been treated with a radiopharmaceutical may NOT be handled or released to its owner or guardian until it has been documented as safe for release to a member of the general public (non-radiation worker).

WA Law states that only essential personnel required for the performance of a procedure shall be in the radiographic room during exposures; and

except for the patient, no unprotected body parts of a patient “holder” shall be in the primary x-ray beam (collimate, collimate, collimate !).

Allow no unauthorized visitors (i.e. - owners) to be in the room during x-ray exams or near a patient that has been administered a radiopharmaceutical for imaging or treatment purposes.

Hazard Awareness = Notice the Postings

When performing Radiography there is an EXTERNAL HAZARD that you mitigate using

the 3 basic Radiation Protection Principles:

TIME: Radiation dose is proportional to theduration of the exposure.

DISTANCE: Radiation dose is proportional to1/(Distance)2.

SHIELDING: Radiation dose is determined by the type and thickness of shielding materials used.

Correct selection of shielding materials depends on the type and energy of radiation.

For the x-rays used for diagnostic radiography (kilovoltage) the shielding material is lead.

-Appropriate attire for all exams. -Lead Apron with thyroid shield and radiation badge at level of thyroid for all occupants of exam room, as well as lead gloves for participants holding film holders.

-No hand holding of imaging devices.

-Use appropriate techniques supplied by department for each machine.

Radiation Safety Common Sense and Radiography

Only radiograph a patient and site if it will produce useful information.

Know that the exam is set up correctly (positioning, tube to part distance, collimation, machine exposure setting) and the room is clear (only essential radiation workers wearing their PPE are present) before you push the exposure button.

PPE (Personal Protective Equipment)= dosimeter, leaded apron, gloves, eye wear, thyroid shield, etc.

Also - Ensure the animal is calm and as still as possible, or sedate; Use non-manual restraint where possible (tape and sand bags); Use a cassette stand or long handled cassette holder whenever possible;

Never direct the x-ray beam at another person or into an adjacent area where others may be exposed inadvertently.

Make sure everyone participating in the procedure stands as far from the x-ray tube and patient (scatterer) as feasible.

Do Not repeat an exposure to achieve “perfection”, the purpose of imaging is to get the diagnostic information that you need.

TLD Ring Thermoluninescence dosimeter Worn on index finger of dominant hand, with the

white face turned towards the radiation source.

OSL Body Badge optically stimulated

luminescence

Worn on torso, below chin and above waist

Dosimetry is PPE and is provided to you for your safety:

Exposure tracking and Dosimeters What you need to know:

The RSO provides a dosimeter (badge) to any radiation worker who is at risk for receiving 10% of their regulatory limit during their work at the VTH;

Wear the whole body badge dosimeter flat against your body, label out, outside the lead apron or thyroid collar and between your neckline and waist;

Wear only your own badge, never let anyone else wear your dosimetry;

Wear your assigned dosimetry whenever working near radiation;

Leave your doimetry at work, in a cool, dry place away from radiation when not in use;

Do not launder the badge and try not to get it soaking wet; Do not open or modify the dosimeter badge;

Turn in your badge for processing in a timely manner at the end of the “wear interval” (monthly or quarterly).

So….what is the Regulatory Limit ?That depends on who and what we’re talking about.

For you, an occupationally-exposed adult:

For under- aged and potentially pregnant radiation workers, or for a member of the general public (i.e.

– a pet owner; custodian; barn worker; etc.)

What are the risks of radiation exposure ?

At this University, most radiation workers Never Receive a Measureable External or Internal Dose !

But, if you do –•The RSO will notify you and investigate the reason(s) for a worker receiving 10% of the annual regulatory limit (i.e. - dosimeter reading divided by 12 if on a monthly dosimeter exchange or 4 if on a quarterly dosimeter exchange).•If needed, the RSO, or the University Radiation Safety Committee will implement appropriate corrective action (president.wsu.edu/office/...committees/radiation-safety.html

Risk for both external and internal radiation exposure

=

Radiation Safety Common Sense when working with dispersible forms of radioactive materials:

• Know who is in charge of the radiation source (AU) and your safety (your direct supervisor; the AU; the RSO);

• Know what exam will be performed and what your responsibilities will be during the imaging procedure and/or when caring for a patient that has received an injectable radiopharmaceutical;

• Wear appropriate PPE = dosimeter, gloves, lab coat or coveralls, water resistant washable shoes or plastic disposable booties, etc.

• NO eating, drinking, smoking, or chewing in the radioactive work space. (Internal contamination)

• Do not store food, drink or personal effects in any area, container, or refrigerator designated for radioactive materials use or storage.

Required by WAC 246-235-130

-All people participating in Nuclear Medicine exams are to wear a lab coat , disposable gloves and radiation badge during Exam. (Plastic disposable booties are worn if fluid or contamination is on floor).

-If the animal has been injected with radioactivity, all bodily fluids (blood, saliva etc.) are considered radioactive and must be protected against.

-Each individual must be examined for contamination by a meter upon exiting of Nuc Med Room from exam.

After- administration of a radiopharmaceutical to a patient = Care of Radioactive Animals :

Animals are not taken out of the stall/cage until Radiology has approved.

Enter the cage/stall wearing gloves, lab coat, badge and disposable booties.

Exit cage/stall and dispose of gloves and booties in “radioactive “ marked reciprocals.

Minimize care of the animal while designated radioactive. No grooming, etc to keep your exposure to ALARA rules.

Anything that comes off of the animal while in the designated radiation status is treated as radioactive and therefore cautions must be followed.

Contact Radiology for any questions regarding animal radiation status.

How can I predict how long does the patient remain radioactive ?The radioactive half-life for a given radioisotope is the time for half the radioactive nuclei in any sample to undergo radioactive decay.

After one half-life, there will be one half the activity of the original sample. After two half-lives, there will be one fourth the activity of the original sample, after three half-lives one eighth the activity of the original sample, and so forth. After 10 half-lives there won’t be much radioactivity left in the patient or in the bedding – but we still perform a radiation survey to verify safety and create a record of the survey.

The primary radionuclides used at the VTH are -Technicium-99m (Tc-99m) for nuclear imaging (bone scans, etc.):

T1/2 = 6 hrsIodine-131 (I-131) for feline hyperthyroid and thyroid carcinoma treatments:

T1/2 = 8 daysMost of the administered dose is excreted in the

urine in the first 48 hrs after the administration; I-131 is then only present in active thyroid tissue

Iodine-131Iodine-131 is used to treat some diseases of the thyroid gland. Iodine-131 is widely used in treating thyroid cancer and other abnormal conditions such as hyperthyroidism. Iodine-131 is a major concern because it is volatile and because it is highly radioactive, having an 8-day half-life.

Radioactive iodine is volatile & if not handled in a fumehood could be breathed in.

Urine will contain up to half of the administered activity of I-131 in the first 3 days.

Who do I contact if I have radiation safety questions or concern ?

Your direct supervisor;

The Authorized User for the particular type of radiation use you have concerns about;

The RSO (radsafe@wsu.edu) or the University Radiation Safety Officer (5-7057);

The WA DOH Office of Radiation Protection – Radiation Machines = www.doh.wa.gov/CommunityandEnvironment/Radiation/XRay.aspx

Radioactive Materials = www.doh.wa.gov/CommunityandEnvironment/Radiation/RadioactiveMaterials.aspx

Where can I find more training suitable for VTH staff and Veterinary students ?

http://www.vet-advantage.com/archives/view_article.php?magazine_id=26&article_id=278

https://www.safetyvet.com/osha/xray1.htm

http://www.veterinarypracticenews.com/vet-editorial-blog/cutting-edge/radiation-protection-conniption.aspx

http://www.rso.wsu.edu/training/training.html

Understanding Radiation - Overview - EPA  

http://www.veterinarypracticenews.com/vet-dept/vet-practice-management/treat-radiation-with-respect-not-anxiety.aspx

https://www.osha.gov/SLTC/radiationionizing/index.html

Everyone must fill out and submit a badging application.

Application link

All females must also read the Prenatal Radiation Exposure module 17.

Test Time!

Follow this link to the test. https://myresearch.wsu.edu/

Use your WSU user name and password to sign in.