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38 Cards in this Set
- Front
- Back
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Ionizing Radiation
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Ionizing Radiation
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Particulate vs. Electromagnetic Radiations
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Particulate vs. Electromagnetic
Radiations |
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Bremsstralung (or Braking)
Radiation |
Bremsstralung (or Braking)
Radiation |
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How Unstable Is It?
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How Unstable Is It?
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Some Isotopes & Their Half Lives
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Uranium - billions
of years - Natural uranium is comprised of several different isotopes. When enriched in the isotope of U-235, it’s used to power nuclear reactor or nuclear weapons. Cesium-137 - 30.2 y Irridium-192 - 74 d Technicium99m - 6 hr |
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What is a “Dose” of Radiation?
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What is a “Dose” of Radiation?
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Radiation Units
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Amount of radoiactive material - Activity - curie (Ci)
Ionization into the air - exposure - roentgen (R) Absorbed energy per mass - absorbed dose - rad Absorbed dose weighted by type of radiation - dose equivalent - rem for most types of radiation 1R approx = 1 rem |
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Types of Exposure & Health Effects
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Types of Exposure & Health Effects
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Dividing Cells are the Most
Radiosensitive |
Dividing Cells are the Most
Radiosensitive |
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At HIGH Doses, We KNOW
Radiation Causes Harm |
At HIGH Doses, We KNOW
Radiation Causes Harm |
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Effects of ACUTE Exposures
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Effects of ACUTE Exposures
Dose (Rads*) Effects 25-50 - First sign of physical effects (drop in white blood cell count) 100 - Threshold for vomiting (within a few hours of exposure) 320 - 360 ~ 50% die within 60 days (with minimal supportive care) 480 - 540 ~50 % die within 60 days (with supportive medical care) 1,000 ~ 100% die within 30 days * For common external exposures 1 Rad ~ 1Rem = 1,000 mrem |
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Radiography Testing
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bring radiography equip to site to test for equipement integrity
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Radiation Monitoring
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Radiation Monitoring
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Accumulated dose
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Accumulated dose
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Radiological survey/Monitoring
Instruments |
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Survey Instruments
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Survey Instruments
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Measuring contamination
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Measuring contamination
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Prepare instrument and
measure background |
Prepare instrument and
measure background |
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Tips for surveying
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Tips for surveying
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Using the instrument
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Using the instrument
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Record results
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Record results
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Perspective on dose levels
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Perspective on dose levels
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Radiation Protection
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Radiation Protection
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Radiation Protection
Reducing Radiation Exposure |
Time
Minimize time spent near radiation sources Distance Maintain maximal practical distance from radiation source Shielding Place radioactive sources in a lead container |
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Radiation Shielding
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Alpha - paper - inhalation injury the greatest
beta - plastic - once inside body creates damage gamma and x-rays - lead neutron - concrete |
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Radiation Safety Program
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Laser safety - Class 1
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CLASS 1 LASER PRODUCT
A class 1 laser is safe under all conditions of normal use. This means the maximum permissible exposure (MPE) cannot be exceeded. |
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Laser safety - Class 1M
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LASER RADIATION
DO NOT VIEW DIRECTLY WITH OPTICAL INSTRUMENTS CLASS 1M LASER PRODUCT A Class 1M laser is safe for all conditions of use except when passed through magnifying optics such as microscopes and telescopes not intended for viewing, cannot produce any known eye or skin injury, max exposure time of 1000 seconds |
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Laser safety - Class 2
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LASER RADIATION
DO NOT STARE INTO BEAM CLASS 2 LASER PRODUCT A Class 2 laser is safe because the blink reflex will limit the exposure to no more than 0.25 seconds |
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Laser safety - 2M
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Class 2M
LASER RADIATION DO NOT STARE INTO BEAM OR VIEW DIRECTLY WITH OPTICAL INSTRUMENTS CLASS 2M LASER PRODUCT A Class 2M laser is safe because of the blink reflex if not viewed through optical instruments. As with class 1M, this applies to laser beams with a large diameter or large divergence, for which the amount of light passing through the pupil cannot exceed the limits for class 2. |
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laser safety - 3A
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Class IIIa
Lasers in this class are mostly dangerous in combination with optical instruments which change the beam diameter or power density, though even without optical instrument enhancement direct contact with the eye for over two minutes may cause serious damage to the retina. Output power does not exceed 5 mW. Beam power density may not exceed 2.5 mW/square cm if the device is labeled with a "caution" warning label, otherwise a "danger" warning label is required. Many laser sights for firearms and laser pointers are in this category. |
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laser safety - 3B
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Class IIIb
Lasers in this class may cause damage if the beam enters the eye directly. This generally applies to lasers powered from 5–500 mW. Lasers in this category can cause permanent eye damage with exposures of 1/100th of a second or less depending on the strength of the laser. A diffuse reflection is generally not hazardous but specular reflections can be just as dangerous as direct exposures. Protective eyewear is recommended when direct beam viewing of Class IIIb lasers may occur. |
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laser safety - 4
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Class IV
Lasers in this class have output powers of more than 500 mW in the beam and may cause severe, permanent damage to eye or skin without being magnified by optics of eye or instrumentation. Diffuse reflections of the laser beam can be hazardous to skin or eye within the Nominal Hazard Zone. Most industrial, scientific, military, and medical lasers are in this category |
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Newton's Inverse Square Law
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Home - General Resources - Formulas and Calculators - Radiography
- Radiographic Inspection - Formula Based on Newton's Inverse Square Law In radiographic inspection, the radiation spreads out as it travels away from the gamma or X-ray source. this law accounts for the fact that the intensity of radiation becomes weaker as it spreads out from the source since the same about of radiation becomes spread over a larger area. The intensity is inversely proportional to the distance from the source. I1 x d1squared = I2 x d2squared Where: I1 = Intensity 1 at D1 I2 = Intensity 2 at D2 D1 = Distance 1 from source D2 = Distance 2 from source |
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alpha emitters
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radium
radon thorium uranium |
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beta emitters
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bio research - hydrogen-3 (tritum, carbon 14, phos-32, sulfur-35
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gamma emitters
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cobolt 60
zinc 65 cesium 137 radium 226 |
