Radiation Safety Protection for Callahan Eye Hospital (OHS_RS502)

Transcription

1 Introduction Welcome to the Radiation Safety Protection for Callahan Eye Hospital Training Course (OHS_RS502). This training is designed and required for anyone working with or around Radioactive Materials (RM) in the Callahan Eye Hospital. This course will be a brief introduction to basic radiation knowledge, policy for sealed sources of radiation, and proper protective methods. Objectives At the conclusion of this course, participants should be able to: 1. Identify the different types of radiation. 2. Identify ways to work safely around different types of radiation. 3. Utilize the correct type of shielding when working with or around radioactive materials. 4. Increase awareness of the various signage and postings that might be displayed work areas. 5. Be familiar with the correct policies and procedures for working with sealed sources of radiation. For further assistance or information contact the Department of Occupational Health and Safety (OH&S) at or visit the OH&S website. Radiation Basics Terms Radiation is energy given off by an atom in its effort to regain nuclear stability. Physical Half-life T 1/2 is the time required for 50% (half) of the activity or amount of radioactive sample to decay away. o Examples 131 I (8.04 days) 365 kev 137 Cs (30 years) 664 kev 125 I (60 days) 35 kev 99 Tc (6.02 hours) 1.4 MeV A=A 0 e -Inl2l(t/T1/2) One ev (electron Volt) = 1.6 X joules Course Material for the Callahan Eye Page 1 Last Updated: 03/25/2015

2 Contamination is the term used to describe the depositing of, or presence of radioactive substances on surfaces or within solids, liquids or gases (including the human body), where their presence is unintended or undesirable (from the International Atomic Energy Agency IAEA) Exposure is the term describing the receipt of energy, yet the radiation does not make physical contact with the object or the body. (Total charge per unit mass) Types of Radiation Type Symbol Penetrating Ability Best Shielding Alpha α Low Air, paper, cardboard, etc. Beta β More penetrating than alpha Low z-number material (Plexiglas, sufficiently thick wood, etc.) Gamma γ Most penetrating of the three High z-number material (sufficiently thick lead) Shielding Scheme Comparison Course Material for the Callahan Eye Page 2 Last Updated: 03/25/2015

3 Exposure Reducing Tools The Big Three Time: the less time spent near the radiation source, then the less exposure received Distance: the greater the distance from the radiation source, then the less exposure received Shielding: use of the appropriate shielding can greatly reduce your exposure from a radiation source o Appropriate shielding does not necessarily mean lead aprons: Lead aprons are designed, primarily, to shield X-Rays. (Energy, or E, typically from kev) Examples of common gamma emitters: I-131, E=365 kev Cs-137, E=664 kev The use of lead aprons must be carefully planned. Wearing a lead apron is not always required PPE. Deposition of the energy from the radiation into the body is not desirable. The wrong shielding could be worse than no shielding! Signage and Postings Always read and pay attention to the various signage and postings in your area. Universal Radiation Caution Symbol A Universal Radiation Caution Symbol (like the one on the right) is called a trifoil. It should be posted in areas where radioactive materials are stored, used, and on items or containers holding radioactive sources. Course Material for the Callahan Eye Page 3 Last Updated: 03/25/2015

4 Radiation Badges (Dosimeters) Radiation badges (dosimeters) are issued to: 1. those who may receive a dose in excess of 10% their annual regulatory dose limit. As occupationally exposed workers, we are allowed an annual limit of 5000 mrem. 2. a declared pregnant worker likely to receive 50 mrem/month. Dosimeters: do not protect you from radiation. are very accurate. may be reused. need to be received and returned on time. should not be stored in or near extreme heat or near other sources of radiation. should not be worn away from work. must never be shared. They are person specific! Notify the OH&S Radiation Safety Program if you become pregnant. The staff can advise you about additional health and safety issues or concerns. Sealed Sources The Radiation Therapy Departments utilize radiation as a method of control and treatment of various types of cancer. Most of the radiation used is contained in sealed sources. The definition of a sealed source is an encapsulated source of radiation that yields the lowest likelihood of radioactive contamination. This radiation does not circulate throughout the patient s body; therefore, no papering requirements are needed. Course Material for the Callahan Eye Page 4 Last Updated: 03/25/2015

5 Interstitial Radioimplant Brachytherapy (Eye Plaque) The definition of brachytherapy is the irradiation of cancerous lesions using sealed radioactive sources by interstitial, intracavitary, or surface application. Other facts about I-125: I-125 emits gamma radiation. The energy of I-125 is 35 kev. The best shielding is sufficiently thick lead. The half-life (T 1/2 ) of I-125 is 60 days. The presence of radiation cannot be detected by our natural senses. Detection of radioactivity must be performed with the proper Radiological Survey Instrumentation. The Eye Plaque and the Seeds The eye plaque comes sealed in a shielded container which is placed in a small cardboard box. The seeds are in a lead container. The Radiation Oncologist and Radiation Oncology Personnel are responsible for the security of the plaque and seeds from arrival to removal and disposal. The patient receives a predetermined number of radioactive sources, called seeds. In this case, the seeds are radioactive iodine (I-125). Sometimes Palladium 103 may be used as well. The gold circle is the plaque. The lines are the seeds. The seeds are affixed within a special bowl or a disc shaped container called a plaque. The plaque is strategically placed to deliver the seeds to a pre-calculated coordinate/location. In addition, the plaque itself serves some shielding for surrounding tissue. These seeds are very small (see image on the right). Should one or more of the seeds come unattached from the plaque, DO NOT TOUCH IT OR THEM! These seeds are radioactive. Call OH&S Radiation Safety Program for assistance. This is a non-radioactive seed. It could easily be mistaken for pencil lead. Do not touch it if it becomes unattached from the plaque! Course Material for the Callahan Eye Page 5 Last Updated: 03/25/2015

6 12 to 24 Hours BEFORE Implementation In order for OH&S Radiation Safety Program staff to protect your health and safety, as well as your staff and patient, please call 12 to 24 hours (if possible) prior to implementation to notify them of the implementation. This allows them to schedule it so that they will be there in a timely manner at the time of the surgery. The Day of Implementation Patients receiving brachytherapy must always be treated in-house not as outpatients. Page the OH&S Radiation Safety Program staff at pager number 7746 when you are ready to take the patient into the operating suite. Please allow 30 minutes for arrival (standard time). When an OH&S Radiation Safety Program staff person arrives, he/she will conduct a pre-surgery survey using a Geiger counter, a device used to detect the presence radiation, to determine the background level and to ensure that no loose seeds are present. This is for the safety and health of all those in the operating area. After the surgery, another survey will be taken, and paperwork will be completed to record the event and readings. After Implementation The patient cannot be released to recovery or from the hospital until one of two regulatory criteria are met. 1. The activity (amount) of radiation in the patient s body is less than 9 mci OR 2. The exposure level at a distance of 1 meter is less than 1.0 mr/hr. In addition, the patient must stay at the facility until the eye plaque is removed. Remember that the Radiation Oncologist and Radiation Oncology Personnel are responsible for the security of the plaque and seeds from arrival to removal and disposal. The patient may receive visitors provided they adhere to the time and safety guidelines imposed by the OH&S Radiation Safety Program. Before the eye plaque is removed, remember to follow the same procedures as before the implementation: 1. Notify the OH&S Radiation Safety Program staff 12 to 24 hours if possible prior to removal. 2. Page #7746 when you are ready to take the patient into the operating suite. Allow 30 minutes for arrival. 3. Allow the staff member to conduct a pre- and post-survey of the surgical area. Course Material for the Callahan Eye Page 6 Last Updated: 03/25/2015

7 Communication with OH&S The main phone number for Department of Occupational Health & Safety is (205) This number is for all programs within the Department. The OH&S Radiation Safety Program has someone on-call 24 hours a day. To contact someone: call UAB paging and ask them to page the Radiation Safety Program on-call person (Pager #7746) OR use the Radio Paging website: Conclusion This concludes the Radiation Safety Protection for the Callahan Eye Hospital (OHS_RS502) Training Course. Please take the assessment at this time. You must score at least 90% or higher to pass. You have two chances to pass. If you fail both times, you will have failed the course and must re-register for the course. This means that you will have a failed course on your transcript. When you pass, print and retain the certificate. You may be asked to present proof of your training. For further assistance or information contact the Department of Occupational Health and Safety (OH&S) at or visit the OH&S website. Want to Learn More? OH&S has many training courses available to all UAB active employees and students. This includes topics such as in-depth radiation training, biosafety, bloodborne pathogens, chemical safety, controlled substances, building life safety, hazardous and medical waste, universal waste, PPE, hazard communication, etc. We have a decision tree ( to assist you in choosing the right course to match the knowledge/skills you may need at work every day as well. If you have any questions or comments, please feel free to contact OH&S. Course Material for the Callahan Eye Page 7 Last Updated: 03/25/2015