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The CD V-777-1 isn’t actually a specific meter. It’s the name given to the entire kit as seen to the right. The kit contains the following items: The.

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Presentation on theme: "The CD V-777-1 isn’t actually a specific meter. It’s the name given to the entire kit as seen to the right. The kit contains the following items: The."— Presentation transcript:

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3 The CD V-777-1 isn’t actually a specific meter. It’s the name given to the entire kit as seen to the right. The kit contains the following items: The CD V-700 Meter The CD V-715 Meter The CD V-742 Dosimeter The CD V-750 Dosimeter charger Batteries Straps Headset Possibly instructions

4 The CD V-777-1 was originally produced in the 1950’s and 60’s in conjunction with the Office Of Civil Defense. Natural nuclear fears arose during the early 50’s due to the Korean War and tensions between the United States and The Soviet Union.

5 Its time for a radiation refresher as we get you ready to use the CDV kit to its fullest extent. The primer starts with an explanation of what radiation exactly is. So, what is radiation ? The term itself is used most commonly to refer to nuclear materials, but radiation is any process that transmits energy through space or a material away from a source in the form of particles or waves. All of this radiation falls along what’s called the electromagnetic spectrum. The spectrum is broken down into ionizing and non ionizing radiation.

6 NON IONIZING RADIATION Non-ionizing radiation is the type of radiation we are most used to and the one we are most exposed to. The chart on the previous slide gave examples of ionizing and non-ionizing radiation. Even though ionizing radiation is more dangerous, non-ionizing radiation can be dangerous as well. For example, one very common, long held concern deals with power line safety, which emits radiation in the form of an electromagnetic field (EMF). There has been no SUBSTANTIAL proof that claims this EMF is indeed dangerous. Other types of non-ionizing radiation, including microwaves, cell phone radiation, continue to be sources of concern for the general public. Ultraviolet radiation (UV) from the sun, however, is known to cause skin cancer.

7 IONIZING RADIATION We will focus our attention on ionizing radiation, since that is the most dangerous form of radiation and the type of radiation the meters in the CD V-777-1 kit are designed to detect. What is ionizing radiation ? Its radiation strong enough to knock off electrons from other atoms. One source of this type of radiation comes from unstable nuclei, like plutonium and uranium, which occur naturally in the environment.

8 Some examples of common forms of ionizing radiation. Uranium and Plutonium are common elements at nuclear facilities The following are sources of ionizing radiation Smoke detectors contain Americium 241, an alpha emitter A photoionization detector (PID) uses ionization to determine concentrations of volatile organic compounds

9 What types of ionizing radiation are there ? Symbol for ionizing radiation Alpha Beta Gamma X-ray

10 Alpha Particles Composed of two neutrons and two protons, identical to a helium atom, but no electrons in the outer shell Have a large mass, and because of this do not travel far, maybe a few inches Travel can be stopped by a piece of paper and your intact skin Actually, one of the most dangerous forms of radiation, IF it gets into your body via ingestion, inhalation, etc. Will ionize (knock off an electron) from air particles as it passes them Examples Of Alpha Emitters Americium 241 - Used in smoke detectors to ionize air molecules Plutonium-239 - used in nuclear weapons. The bomb dropped on Nagasaki used Pl- 239 Uranium-238 - Most common use for nuclear reactors. Depleted Ur used by military in shielding for tanks. Thorium-232 - most widely used in lantern mantles for the brightness it imparts Radon-222 - found at low concentrations in almost all rock and soil. Can creep up through soil and build in amount inside buildings Polonium-210 -

11 Beta Particles Essentially a discharged electron, about 2000 times smaller than an alpha particle Have a small range, usually a couple of feet Will ionize other atoms, but not as much an an alpha particle Does have more penetrating power, but can be stopped by a sheet of aluminum foil. High energy beta particle can penetrate skin Examples of beta emitters: Tritium - a hydrogen isotope, used to illuminate exit signs and watches cobalt-60 - used to sterilize medical equipment, also a source for radiography and food irradiation strontium-90 - radioactive source for depth gauges, tx of bone cancer technetium-99 - radioactive waste from medical procedures and nuclear accidents iodine-129 and -131 - Used extensively in nuclear medicine, especially helpful in thyroid treatment cesium-137 - Used heavily in industry as a depth gauge, and to detect liquid flow in underground pipes

12 Gamma Rays Very high energy Have no mass and no electrical charge-- they are pure electromagnetic energy. Travel at the speed of light and can cover hundreds to thousands of meters in air before spending their energy Can pass through many kinds of materials, including human tissue. Very dense materials, such as lead, are commonly used as shielding to slow or stop gamma photons. Examples of gamma emitters: Cobalt-60 sterilize medical equipment in hospitals pasteurize certain foods and spices treat cancer gauge the thickness of metal in steel mills. Cesium-137: cancer treatment measure and control the flow of liquids in numerous industrial processes investigate subterranean strata in oil wells measure soil density at construction sites ensure the proper fill level for packages of food, drugs and other products.

13 The radiation energy absorbed is called the dose and when considering doses to human tissue, it is measured in units of “rems.” Frequently when considering doses, the unit used is the millirem which is one one-thousandth (1/1000) of a rem

14 RAD, REM, ROENTGEN, what gives ? All these terms used to measure radiation can get very confusing. When do you use either of these 3 terms ? They are all essentially considered the same. One RAD is equal to one REM and one Roentgen. The actual definitions: Roentgen - The roentgen measures the energy produced by gamma radiation in a cubic centimeter of air. Its basically a measure of the amount of radiation something gives off. RAD - Stands for ‘radiation absorbed dose’, and specifically reflects the amount of radiation an object, specifically a human, has actually absorbed. REM - Stands for ‘Roentgen Equivalent Man’, and is designed to reflect the differences in absorbed doses based on the type of radiation you are exposed to. So in order to get the does in REM, you need to multiply the dose in RAD X a coefficient that relates to what type of radiation. For X Rays and Gamma rays, multiply by 1, neutrons multiply by 5, and alpha particles multiply by 20. You can see by those numbers that alpha particles, once absorbed, damage the body the most.

15 Radiation Doses Acute Radiation Dose Effects in Millirem 450,000.0 (450 REM) Acute dose, LD 50/60 (a lethal dose to 50% of a population within 60 days if no medical treatment) 100,000.0 (100 REM) Acute dose, radiation sickness, reduced blood count, recovery 25,000.0 (25 REM) Acute dose, reduced fertility, and temporary sterility 10,000.0 (10 REM) Minimum acute dose for which prompt effects are detectable

16 Radiation Doses in Millirem from Various Exposures (Annual Dose Unless Otherwise Stated) 10,000.0 Dose to Chernobyl evacuees 5,000.0 U.S. Occupational Dose limit 2,000.0 Tobacco smoking 1,500.0 Underground uranium mines 400 – 800.0 St. Peters Square, Rome 600.0* Pelvic x-ray exam 500.0* Barium enema x-ray exam 500.0 U.S. Occupational Dose limit for pregnant women per 9 months 480.0 Denver, Colorado 360.0 Average U.S. dose 100.0 Dental x-ray dose to center of cheek 20.0 1 Chernobyl per year 15.0* Chest x-ray 7.0 Nuclear testing (peak year) 4.0 Fallout 2.0 Airplane trip coast to coast 1.0 Nuclear power 0.5 TV at surface 0.1 Sleeping with another human

17 The highest lethal doses seen by victims of Hiroshima and Nagasaki was in the range of 700 REM

18 Radiation Limits For Fire Service Operations The outside of the hot zone should be established at 2 mr/hr. Exposure Limits How much radiation can I be exposed to ? For the radiological industry workers: 5 R or 5000 mR per year

19 Radiation Limits For Fire Service Operations We Risk A Lot To Save A Lot We Risk A Little To Save A Little… Our exposure limit is dependent on what is at stake

20 Radiation Limits For Fire Service Operations The average American’s risk for getting cancer is….

21 Radiation Limits For Fire Service Operations 5 Rem = Any Response 10 Rem = Valuable Property 25 Rem = Lifesaving Greater than 25 Rem = Lifesaving Greater than 25 Rem = Lifesaving (Voluntary Basis Only) (Voluntary Basis Only)

22 Radiation Limits For Fire Service Operations 5 Rem = Any Response 10 Rem = Valuable Property 25 Rem = Lifesaving Greater than 25 Rem = Lifesaving Greater than 25 Rem = Lifesaving (Voluntary Basis Only) (Voluntary Basis Only) 25 Rem = a 2% increase in cancer risk, from 24% to 26%

23 Radiation Limits For Fire Service Operations 5 Rem = Any Response 10 Rem = Valuable Property 25 Rem = Lifesaving Greater than 25 Rem = Lifesaving Greater than 25 Rem = Lifesaving (Voluntary Basis Only) (Voluntary Basis Only) 50 Rem = a 4% increase in cancer risk, from 24% to 28%

24 Radiation Limits For Fire Service Operations 5 Rem = Any Response 10 Rem = Valuable Property 25 Rem = Lifesaving Greater than 25 Rem = Lifesaving Greater than 25 Rem = Lifesaving (Voluntary Basis Only) (Voluntary Basis Only) 100 Rem = a 5 % mortality rate

25 Used to detect gamma radiation only Can be used for 150 straight hours Can be used in any humidity level Very powerful battery, be careful Designed for ground survey Measures 0-500 r/hr

26 How To Use The CD V-715  Install one “D” cell battery  Turn the selector switch to ‘zero’ and let the unit warm up for two minutes  After two minutes, use the ‘zero’ knob to zero out the instrument

27 How To Use The CD V-715  Turn selector switch to ‘circuit check’ and confirm the needle goes into the red ‘circuit check’ area on the gauge  Check all marks (X100, X10, X1, and x.01) and confirm no major movement of needle. A major movement would be past the ‘2’ mark on the gauge.

28 Used to detect gamma and beta radiation Designed for low level measurements Very powerful batteries, be careful Used for personnel monitoring Check for degree of contamination of food and water Measures from 0-50 mR/hr

29 How To Use The CD V-700  Install 5 “D” cell batteries  Turn selector switch to the “X10” mark and allow 30 seconds for warm up  Rotate probe shield to fully open position

30 How To Use The CD V-700  Place probe as close as possible to operational check source on side of meter.  The meter should read between the range written on the sticker on the back of the meter during its last calibration. If it doesn’t, do not use.

31 How To Use The CD V-700  Radiation doses exceeding 50 mR/hr to 1 R/hr will produce off scale readings and will saturate the meter. This could result in a reading of zero or less than full scale. Use a higher range instrument (CD V-715)

32 How much radiation have I been exposed to, if any ? Measures accumulated gamma doses from 0-200 R. Difficult to read, difficult to zero out or “charge” Will require charging using the CD V- 50.

33 Installing the battery in the CD V-750 dosimeter charger Place the side with the exposed needle like object onto the port of the CD V-750 Look through the dosimeter and use the ‘up scale’ and ‘down scale’ knob to zero out the dosimeter

34 ROENTGENS 020406080100120140160180200 Rotate this slowly…...until this vertical black line is on the zero

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