Presentation on theme: "Division of Medical Physics and Radiation Safety 617 638 7052 Radiation Safety Awareness for This training does not substitute for Basic Radiation Safety."— Presentation transcript:
Division of Medical Physics and Radiation Safety 617 638 7052 Radiation Safety Awareness for This training does not substitute for Basic Radiation Safety Training. You will Chemistry Students
Disclosure This training does not substitute for Basic Radiation Safety Training offered to BU Radioisotope Authorized Users. You are only authorized to use radioactive material for during this class-XX.XX.
Massachusetts Department of Public Health Radiation Control Program (RCP) issued Radioisotope License to: Boston University and Boston Medical Center (BU) and (BMC) Medical + Research Patient Use X-ray, Therapy Units, and Lasers Radioactive Materials Licensure
4RPO BROAD SCOPE MATERIALS LICENSE BU RSC Permit Holder User DMPRS Radiation Supervisor/ Lab Coordinator
Radiation Use at BU and BMC Radiation is used at BU and BMC as: Radioactive Materials Radiation Generating Devices Irradiators Radiation Protection Office\Dept\12 Training Program Management\Maintenance Training
Radiation Uses at BU and BMC Examples: Research with radioisotope tracers to study diabetes, infection, cancer and DNA Medical Use Irradiating patient’s blood to prevent transfusion reactions Heart Scans Treating Prostate Cancer Diagnostic X-rays (Dental, Chest, CT, etc.)
7RPO ALARA An acronym for "As Low As Reasonably Achievable." It means making every reasonable effort to maintain exposures to ionizing radiation as far below the dose limits as practical. The goal of radiation protection is to keep radiation doses As Low As Reasonably Achievable BU is committed to keeping radiation exposures to all personnel ALARA
The National Council on Radiation Protection and Measurements (NCRP) published a study of the U.S. population’s exposure to radiation in 2009. The chart below shows sources that contributed to an annual average dose of 620 millirem per year. This is a national average, individual exposures will vary. Sources of Radiation Exposure NCRP Report No. 160 (2009)
9RPO Do you work directly with a source of radiation? No Badge Required Is the radiation source an isotope or a machine? No Yes Do you work with at least one of the following isotopes (greater than activity indicated)? (badge type in ( ). Brachytherapy Sources (1,4) >1 mCi/qtr. of gamma or positron emitter (1,4) >1 mCi high (>500 keV) max energy Beta emitter (1,4) Nuclear Radiology Isotopes (1,4) Do you work with any one of the following machines? (badge type in ( ) Fluoroscope (2,3) LINAC (1) Diagnostic x-ray (2,3) CT (2,3) IsotopeMachine A badge is mandatory A badge is voluntary Yes No Badge Type 1 – Whole body 2 – Collar 3 – Waist 4 - Ring Dosimetry Requirement Decision Tree No
Basic Terms Radiation: energy in transit in the form of high speed particles and electromagnetic waves. Radioactivity: Characteristic of an unstable atom that releases energy in the form of a particle or electromagnetic wave. 12
Types of Ionizing Radiation Alpha particles: contains 2 neutrons and 2 protons, which is ejected from the nucleus of a radioactive atom. Beta particles: A high-speed electron or positron, usually emitted by an atomic nucleus undergoing radioactive decay. Electrons carry a negative charge. X-rays: Electromagnetic radiation originating in the electron field of an atom. Gamma rays: A gamma ray is an electromagnetic radiation originating in the nucleus of an atom. 13
Types of Radiation Ionizing Radiation: Radiation capable of liberating electrons from an atom. ex. beta particles, x-rays Non-ionizing radiation: Radiation not capable of liberating electrons, but can excite the atom. ex. microwaves, radio waves, lasers 14
15RPO Terms and Definitions Radiation: Energy in transit in the form of high speed particles and electromagnetic waves. Radioactivity: Characteristic of an unstable atom that releases energy in the form of a particle or electromagnetic wave.
16RPO Units There are two systems of units used in the measurement of radioactivity and radiation dose. The older units (Curie,Rad and Rem) - the American System and U.S. regulatory units. The widely-used international units (Becquerel, Gray and Sievert) – International System or “SI” system.
17RPO Radiation Quantities Curie: 3.7x10 10 disintegrations per second or 2.2x10 12 disintegrations per minute. 1 curie (Ci) = 2.2 x 10 12 dpm 1 millicurie (mCi) = 2.2 x 10 9 dpm 1 microcurie (µCi ) = 2.2 x 10 6 dpm Example: 100 µCi = 0.1 mCi = 2.2 x 10 8 dpm Becquerel: One disintegration per second. (SI system) 1 mCi = 37 Megabecquerels (MBq) 1 µCi = 37 kilobecquerel (kBq) Example: 0.1 mCi = 3.7 MBq = 100 µCi
RPO Radiation Units Roentgen: unit for measuring the amount of ionization in air (exposure) due to gamma or x-rays. RAD: Radiation Absorbed Dose. Unit used to describe the amount of energy absorbed from radiation in any type of medium. 100 rads = 1 Gray (SI)
19RPO Radiation Units REM: Unit used for measuring human dose equivalent. 100 rem = 1 Sievert (SI) 1 rad of alpha = 20 rem 1 rad of beta = 1 rem Note: Two different types of radiation may deliver the same absorbed dose, but produce a different biological affect, and hence, dose equivalent. 1 rad of alpha = 20 rem 1 rad of beta = 1 rem
20RPO Half-Life The time required for any given radioisotope to decrease to one-half of its original activity by radioactive decay. This period of time is called the half-life. P 32 - 14.3 days C 14 - 5730 years H 3 - 12.3 years S 35 - 89.7 day I 125 - 60 days
21RPO External Exposure Common isotopes with external exposure potential ex: P-32, I-125, Cr-51 Not all radioisotopes are external exposure hazards ex: H-3, C-14, S-35
External Radiation Three ways to reduce exposure from external radiation sources Time Distance Shielding
30 min work time in a 40 mR/hr field= ???.5 hr x 40 mR/hr = 20 mR Time and exposure have a linear relationship. As time decreases, the exposure decreases proportional to time.
50 cm100 cm200 cm Distance from source: Dose rate:40 mR/hr10 mR/hr2.5 mR/hr Distance and exposure have an inversely proportional relationship. As distance increases, photon exposure decreases at the rate of the inverse of distance squared.
99m Tc dose in shielded Pb carrying case The type of shielding that is suitable for one type of radiation may not be suitable in shielding another. Always consult the Radiation Safety Office to ensure that your shielding is appropriate.
26RPO How To Minimize External Exposure DISTANCE : Inverse Square Law 10 mR/hr @ 1 ft At 2 ft. - What is your exposure? 10 mR/hr = 2.5 mR/hr 2 ft. 2
27RPO Shielding Alpha particles can be stopped by a sheet of paper. Most Beta particles can be stopped by 1-2 cm of Plexiglas. Most gamma and x-ray photons can be absorbed by several cm of lead. Neutrons may require several feet of concrete.
RADIOACTIVE MATERIAL CAUTION Radioactive material used or stored Radioactive Labeling
CAUTION Radiation Label Refers to areas accessible to personnel, in which a major portion of the body could receive a dose of 5 mrem in any one hour at 30 centimeters from the radiation source or from any surface that the radiation penetrates. RADIATION AREA Do NOT enter unless authorized
32 Contamination Definition: Radioactive material where it shouldn’t be. e.g. floors, bench tops, hands All radioisotopes have contamination potential even if they do not have external exposure potential. The goal is to prevent contamination from getting on to your skin and/or inside your body.
33RPO Skin Contamination Cool water, mild soap 2-3 minutes working up a good lather, dry No harsh chemicals or detergents Survey for contamination Notify the RPO 617-638-7052
34RPO SPILLS S Stop all work and contain spill W Warn others I Isolate Area M Minimize exposure and monitor N Notify RSO
35RPO Proper Survey Technique Use appropriate survey meter Check battery Audible on Check background level Audio On/Off Switch Rotary Switch Off Battery Check Scalar Multiplier Battery Compartment
RPO Surveys Geiger Counters used for all isotopes (EXCEPT H-3) Gamma Scintillator NaI Note: Contamination Surveys use for I-125 use Gamma Scintillator (NaI) probe. End WindowPancake Portable Survey Meter Gamma Scintillator (NaI) probe
RPO Survey Meter Face Plate X 1 Top scale : 0 - 4.2 Kcpm on X 1 multiplier X 100 Bottom scale: 0 – 200 mR/hr on X 100 multiplier only X 1 Middle scale: 0 – 2.0 mR/hr on X 1 multiplier
38RPO Wipe Tests A wipe test only assesses removable contamination. A dry material to wipe an (100 cm 2) area of potential radioactive contamination. For H-3, a wipe test is the only means to assess potential contamination. For P-32, S-35, C-14, use Geiger Mueller Probe for fixed and removable contamination surveys Liquid Scintillation Counter
39RPO Container Labeling You must ensure that all containers possessing radioactive material are labeled with: Radioisotope Quantity Date Chemical Name
40RPO Sulfur 35- Amino Acid Precautions Because of volatility: Use fresh stocks Open Stock vial in hood Place charcoal in incubators, water baths, etc. Monitor with GM (pancake) especially centrifuges, incubators, bag sealers
Working with Eppendorf tubes RPO41 Use flat top tube opener to reduce radiation levels to fingers
43RPO Rad. Waste Guidelines Put radioactive needles etc., in “radioactive” sharp container No liquids No lead pig or radiation labels in rad. waste (deface all radiation labels) Assure rad. waste container labeled to prevent housekeeper from emptying trash Call DMPRS for any questions at 617-638-7052
44RPO Radiation Safety Records All records must filled out and up to date! Inventory Surveys Waste logs Sink logs
45RPO Radiation Safety Checklist All persons completed required training? Are radioactive materials secured? Do you use a survey meter and/or wipes to assess exposure and/or contamination? No eating, drinking or application of cosmetics in the laboratory? Report spills to Radiation Safety 617 638 7052?
Security Security involving research material All radioactive material must be secure from unauthorized removal or access. The Authorized User of radioactive material must maintain constant surveillance, and use devices or administrative procedures to prevent use by unauthorized personnel.
47RPO Security of Radioactive Material You can do one or more of the following: Keep radioactive material in constant view Lock up radioactive stock solutions Lock the laboratory Always keep the access door to your floor of the building locked. ( Use Key Card Access or the Combination Lock )
Risk of exposure to ionizing radiation Minimal Exposure = Minimal Risk If 100,000 persons were exposed to 10 Rem of radiation each, 800 excess cancer deaths would be expected during their remaining lifetimes in addition to the nearly 20,000 cancer deaths that would occur in the absence of radiation. -BEIR V Report, page 162 - 1989 Latest Biological Effects Studies
THE END Please complete the Radiation Quiz to fulfill your training requirements If you have any questions, please contact the RPO at 617-638-7052