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Radiation Can Be Fun….!!!! But R.E.S.P.E.C.T. it. Radiation Safety Training Nuclear Medicine Technologists. G eneral Safety. P atient Safety. S taff Safety. Overview. Federal & State Regulatory Concerns Natural Sources of Radiation Exposure Occupational Sources of Radiation Exposure
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Radiation Can Be Fun….!!!! But R.E.S.P.E.C.T. it.......
Radiation Safety TrainingNuclear Medicine Technologists • General Safety • Patient Safety • Staff Safety
Overview • Federal & State Regulatory Concerns • Natural Sources of Radiation Exposure • Occupational Sources of Radiation Exposure • Regulatory Exposure Limits • Basic Radiation Safety Principles • Biological Effects • UCHC Safety Requirements
Radiation vs. Radioactivity • Radiation - Energy in transit in the form of high speed particles and electromagnetic waves. • Ionizing Radiation - Radiation with enough energy so that during an interaction with an atom, it can remove tightly bound electrons from their orbits, causing the atom to become charged or ionized. • Radioactivity - Spontaneous transformation of an unstable atom and often results in the emission of radiation. This process is referred to as a transformation, a decay or a disintegration of an atom.
X-RAYS γ GAMMA RAYS Gamma Decay
External vs. Internal Radiation Exposure • External exposure – x-rays, brachytherapy patients, iodine therapies, dose preparation and administration • Internal deposition – contamination from an iodine patient resulting in an ingestion of radioactive materials
§20.1201 Occupational dose limits for adults. • The licensee shall control the occupational dose to individual adults, except for planned special exposures under §20.1206, to the following dose limits. • (1) An annual limit, which is the more limiting of -- • (i) The total effective dose equivalent being equal to 5 rems (0.05 Sv); or • (ii) The sum of the deep-dose equivalent and the committed dose equivalent to any individual organ or tissue other than the lens of the eye being equal to 50 rems (0.5 Sv). • (2) The annual limits to the lens of the eye, to the skin of the whole body, and to the skin of the extremities, which are: • (i) A lens dose equivalent of 15 rems (0.15 Sv), and • (ii) A shallow-dose equivalent of 50 rem (0.5 Sv) to the skin of the whole body or to the skin of any extremity.
Radiation Exposure Limits Rem Per Year 5 or 5,000 mrems 50 or 50,000 mrems 15 or 15,000 mrems 50 or 50,000 mrems Type of exposure Total effective dose equivalent (TEDE) which is the sum of the deep-dose equivalent (for external exposures) and the committed effective dose equivalent (for internal exposures) for the whole body Sum of the deep-dose equivalent and the committed dose equivalent to any individual organ or tissue other than the lens of the eye Eye dose equivalent (lens of the eye) Shallow dose equivalent to the skin or to any extremity
1.25 18.75 7.5 (1,250 mrem) (5.0 rem/yr) (18,750 mrem) (75 rem/yr) (7,500 mrem) (30 rem/yr) Radiation Exposure Limits (State of Connecticut Administrative Regulations Sect. 19-24-5) Type of Exposure Rem Per Calendar Quarter Whole body; Head and trunk; Active blood-forming organs; Lens of eyes, or gonads. Hands and forearms; Feet and ankles. Skin of whole body. Fetus 500 mrem Total Gestation (0.5 rem)
Time Distance Shielding Contamination Control Basic Radiation Safety Principles
g - gamma radiation g g g g g 10,000 2,500 g g 1 cm 2 cm 400 5 cm g 10 cm 100 g g 20 cm 25 g g Inverse Square Law(137Cs 192Ir) • For a point source, the intensity varies inversely as the square of the distance from the source.
Whole Body Radiation Badge Worn Underneath Pb Apron Collar Radiation Badge Worn Outside Pb Apron At Neck Level Extremity Radiation Badge Worn on Primary Hand Closest to Radiation Source BLACK ICON RED ICON Radiation Exposure Monitoring
THYROID COUNTS • Within The same week for 131-I • Within 7 days 125-I • MDA about 0.0005 UCI, o.5 NCI • MDD, 131-i 0.5 mrem TODE
AREAS REQUIRING FURTHER DISCUSSION • Thyroid counts • Signatures • Spills • Package surveys • Gloves in hot lab-monitoring • Access to the department • Incorrect 99m-TC dose
PACKAGE WIPE TEST AND EXPOSURE RATE LIMITS CONTAMINANT AVERAGE DPM/CM^2 DPM/100 CM^2 Beta/Gamma 22 2200 Alpha 2.2 220 T.I. = mrem/hr @ 1 meter from sufrace TRANSPORT INDEX MAX. MR/HR SURFACE LABEL 0 (<= 0.05) < 0.5 mr/hr White I 0.05 to <= 1.0 0.5 to <= 50 mr/hr Yellow -II 1.0 to <= 10 50 to <= 200 mr/hr Yellow- III > 10 200 to <= 1000 mr/hr Exc. Use!!!
HOT LAB PPE • Personnel protective equipment required for entry • Gloves • Dosimetry • Lab coat
INJECTION ROOM • PPE highly recommended when entering • PPE required if injecting • PPE required if assisting • PPE required if handling any possibly contaminated item
OTHER AREAS • PPE required • Injecting rad mat • Handling/assisting patients who have been injected • Handling items that may be contaminated
PERSONAL SURVEYS • A survey of the hands and other body areas with documentation • Suggested very strongly to survey shoes • Report contamination to RSO • This is an NRC requirement
EXAMPLE • What label is required on a package with the following monitoring results ? • 10 MR/hr surface, 1 MR @ 1m, wipe test BKG. 285 CPM, gross CPM of 1250
EXAMPLES • Background 430 CPM, outside wipe 360 CPM? • Background 310 CPM, outside wipe 349 CPM? • Background 265 CPM, outside wipe 5500 CPM?
Nuclear Medicine Diagnostic Procedures • Radionuclides with short half lives (e.G., 99mtc @ 6 hrs) • No significant external radiation exposure hazard to staff or family • Contamination precautions and universal precautions should always be followed
Pregnancy Declaration • NRC requires a signed declaration of pregnancy for occupational workers to limit exposures to 500 mrem/9months or 50 mrem in any one month.
Emergency Procedures • Address medical emergency first !! • Follow radiation patient code procedures. • If the patient should die or require emergency surgery, contact a member of the Radiation Safety Office immediately at X-2250.
Radiation Exposures from Consumer Products 1 1Adapted from NCRP 95
Radiation Exposures from Consumer Products 1 1 Adapted from NCRP 95 2BEDE = Bronchial Epithelial Dose Equivalent; WB = Whole Body; IDF = Ingestion Dose from Foods BMDE = Bronchial Mucosa Dose Equivalent; CGDE = Corneal Germinal Dose Equivalent; SODE = Selected Organ Dose Equivalent
Smoking a pack and a half of cigarettes a day will add about 1,300 mrem/year to one's effective dose Flying from New York to San Francisco results in the absorption of an extra 2-3 mrem of cosmic radiation 6-8 from NY to Japan Radiation Exposures From ?