Radiation 101

Discussion in 'Survival Articles' started by survivalmonkey, Dec 15, 2005.

  1. survivalmonkey

    survivalmonkey Monkey+++

    A little very basic radiation information for those who care and don't already know.

    DOSIMETERS are one of the most useful of radiation instruments. Radiation is undetectable by humans as it has no smell, feel or other indicator of it's presence. It causes cumulative damage to the body over time. The amount you receive in a period of time is known as DOSE. If you are exposed to a RATE of 10 rads for 2 hours you then receive a DOSE of 20 rads. To measure RATE one needs a RATE meter, such as a Geiger Counter or Survey Meter. More on those in another thread.

    To measure your personal DOSE requires a DOSIMETER (dose meter). There are several types but the one of interest to us here is a "pen" or electrostatic type. They have been made since the forties and remain essentially the same today, still being manufactured. They can be purchased new for about $100 each or surplus for just a few dollars. They are very rugged and rarely fail. Most exhibit a little leakage but it is easily compensated for. Leakage is a manufacturing defect from what I have read. Those few with problems are easily identified and can either beused with the known fault or trashed. I leak test all of mine and mark the leak rate on the instrument for future reference and compensation. Those with high leak rate get tossed while th low leaakage ones are good to use.

    The principle of these is simple. An electrostatic charge is impressed on the instrument until the indicator rests at zero. If radiation penetrates the unit, a small amount of that charge is lost in proportion to the amount of radiation. As charge is lost, the indicator moves up scale. Leakage, the most common fault, is when the indicator moves slowly up scale when no radiation is present (other than background). To test for leakage, charge each instrument to a zero reading and place them in a location where they will not be disturbed. Read them every 12 hours and record where the indicator is. After several 12 hour periods (or other convienent tiem) dust off the calcutator and figure the rate of change per 12 hours. Use felt tip marker and put the leak rate on each instrument. Just that simple!!! Example: After 36 hours, a reading of 12 rads is shown. Leak rate, therefore is 36/12=3 periods. 12/3=4 rads per period Mark as 4/12. In use, the leak rate is subtracted from the reading during exposure. Leak and exposure both need to be for same time period. A few refuse to charge, have "sticky" indicator, cloudy or internally dirty viewing window; these get tossed.

    Dosimeters are available in several ranges. I have Civil Defense ones that are 0-200 RADS (Gold Clip, CD V-742), 0-20 RADS (Green Clip CD V-730 ) and 0-200 MILLIRADS (Black Clip CD V-138 ). The instruments are most accurate at 1/2 scale. If you accumulating a DOSE of 100 RADS in a day or two, the Shit has truly splattered all over the fan!! These 0-200 R are the range most commonly sold and the cheapest. By all means, get a few, test and mark them for leakage and put in your stash. The lower range ones are likely to be more useful in anything short of terrorist attack close by so try to get a few of those as well. Always carry the higher range AND lower range when exposure is possible so that if you exceed your low range one you can have some idea of by how much! There are nifty electronic dosimeters out there. They are more expensive, require batteries and are more complex, therefore, maybe, less reliable. The CD type should be your first purchase and ALWAYS kept around as a reliable back-up.

    Chargers: Many variations exist. CD V-750 is the yellow box you often see for sale. They use 1 "D" cell and also provide illumination. They are a simple and reliable electronic circuit that dates to the early sixties. Light is provided by a one cell flash lite bulb. Most common problem is leaking batteries. DO NOT store with battery installed!! If you buy one that has a lot of corrosion, set aside for parts and buy another.

    Lamp failure: Merely requires a new bulb.

    "Noisy" pot. The adjusting pot can (and often does) get scratchy, just like old volume controls did. A small squirt of electronic control cleaner will often cure it.

    Circuit failure: Set aside for parts. The transistor used hasn't been made for 30 years! Substitutions are possible if you are into electronic repair and have the time. This sort of failutre is actually very rare.

    Self powered type PP1578A/PD as used by the Army. I recently obtained a number of these and all check good. Last Army "calibration" was 1984. No battery required, simple and rugged. Disadvantage is they do not provide illumination. A window or flashlight is required. Due to not needing a battery they are great for SHTF!! We all know how difficult it could get to obtain batteries if the balloon ever goes up!!

    Use of the above goodies:

    An excellent reference book is the FEMA Radiation Safety In Shelters circa 1983. They can also be purchased for around $15. which I STRONGLY suggest!! (Any idea how long the internet will operate after a SHTF event?)
    Dunerunner, arleigh and Tempstar like this.
  2. Witch Doctor 01

    Witch Doctor 01 Mojo Maker

    Check with the local VFD sometimes they offer FEMA radiological monitoring g courses.... Well worth the time... In figuring dosage you may also want to get an estimated PF factor for your shelter and a set of TOM's Excel spread sheet for keeping a record of fallout/dosages/ etc...
    Dunerunner likes this.
  3. ghrit

    ghrit Bad company Administrator Founding Member

    1) RAD =radiation absorbed dose
    2) The dosimeters described in melbo's post above are (in general) for gamma measuring. They are shielded against beta, and cannot see alpha or neutron at all. That said, beta and alpha require direct contact to flesh to have an effect. Alpha and beta require specialized dose measuring devices. (As does neutron radiation, a whole 'nuther subject.)
    3) Those dosimeters also measure background (cosmic radiation, for example, found everywhere) and often that is mistaken for instrument drift. 'Tain't necessarily so, the only sure ways to tell is if one instrument varies more than the average of a group OR if it is stored in a very heavily shielded location.

    The RAD measurement has an indirect effect on actual affects on the human body since the energy of the incident radiation is variable. Since I'm sure there have been large advancements made since I did the health physics bit back in the Navy, I'll defer to those with more current knowledge.
    Last edited: Jun 30, 2014
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  4. oil pan 4

    oil pan 4 Monkey+++

    If you were close enough to have to worry about neutron radiation you probably got vaporized in the initial blast or at the very least absorbed an acute lethal dose of everything else.
    Alpha only travles 2 inches in atmosphere is harmless as long as you don't ingest a source.
    Ura-Ki, Dunerunner and sec_monkey like this.
  5. T. Riley

    T. Riley Monkey+++

    Purchase link?
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  6. arleigh

    arleigh Goophy monkey

    " Radiation network "
    are a group of individuals like yourselves, that have their geiger counters, all hooked up on line ,sharing the varying degrees of exposure we are being subject to.
    they also list equipment that is available you might be interested in.
    The best pick up is the disk type. it has the widest range and most sensitive.
  7. Motomom34

    Motomom34 Monkey+++

    As @arleigh said, radiation network is good. Radiation Network Scroll down a bit and they have equipment listed and other information.
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  8. duane

    duane Monkey+++

    Worked a little with stuff in the military in the 1950's and the way we treated it was criminal by todays standards. My limited take on radioactive particles is that ingesting or getting it in your lungs or blood stream is the biggest danger. The shielding of a piece of paper or a couple inches will save you from alpha, but if you get cut and get it in your blood stream, or eat and get it in your gut, or you get in your lungs, you are in big trouble and probably going to die, just a question of when..
    Ura-Ki likes this.
  9. oil pan 4

    oil pan 4 Monkey+++

    Yes real bad alpha emitters like polonium 210 will kill you with as little as something like 5 nano grams.
    Ura-Ki likes this.
  10. ghrit

    ghrit Bad company Administrator Founding Member

    Won't bother you a bit if you don't eat or breathe it The radiation is not particularly dangerous, but it is exceedingly toxic, as are all heavy metals. Visquine will stop it.
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  11. Cruisin Sloth

    Cruisin Sloth Special & Slow

    Since I work in WEIRD / ALL over I carry wallet sensors on the outside (wallet) & in a front pocket of leg front pouch /RT0 pouch and every week I send them in Or check colour .
    I got badly inflected at a welding area that was doing penetration depth checks , someone forgot something, I was alerted 4 days later when I checked & swapped senors .
    So it is out there . I figure Im Kid-less (65yo+) and any bad cancer has had a sample ;) .
    Ura-Ki likes this.
  12. duane

    duane Monkey+++

    I have read that if plutonium was in a cut in your finger, they amputated it or at least that's what they told us in the USAF. Nasty stuff, it burns, they used to encase it in nickle for the pits, a lot of land north of Denver, the old Rocky Mtn Arsenal, was polluted by a fire in the facility that processed the materials for the war heads. Most of the miners in the early uranium mines in the 40's died of lung cancer etc from mining the ore. Personal bias, I would be more worried about ingesting alpha emmiters than by the gamma radiation at survivable levels. We had "Micky Mouse" badges in the AF for detecting radiation that we wore around our necks and were checked each week. Joke was that if they showed a high accumulated dose, you would have time to kiss your a** good by before you died.
    Yard Dart likes this.
  13. arleigh

    arleigh Goophy monkey

    I thought lead was the prescribed insulator .
  14. BTPost

    BTPost Stumpy Old Fart,Deadman Walking, Snow Monkey Moderator

    Actually, Gold works just as well, if not better, as an insulator... It is just a whole lot more expensive....
  15. ghrit

    ghrit Bad company Administrator Founding Member

    Ah, lead is a poor insulator for anything at all electrical or thermal. It'll work for a faraday enclosure if that is where you are headed. It will do very well against gamma, alpha, and beta radiation as long as it's thick enough (variable depending on the gamma energy.) Total waste against neutron radiation. Neutrons are somewhat unique when it comes to shielding.

    Same thinking goes with gold as with lead. 'S'funny, but uranium is a pretty good gamma shield as well, but like other heavy metals you really do NOT want it in your air, water, and burgers. Depleted uranium has been used for "certain" radiation shielding applications for quite a few years.
    BTPost likes this.
  16. oil pan 4

    oil pan 4 Monkey+++

    2 feet of concrete would be cheaper than 2 inches of lead. Unless you have a free source of one or the other.
    Water is also a good shield. All the raw nuclear waste in the country is stored in temporary storage pools.
    On deep space missions the the astronauts are going to use any mass available to put between between them selves and the sun during a solar storm.
    Full Water containers, food packes, freeze dried poo, ect.
    When a class x solar storm hits when you are one astronomical unit away from the sun and outside the earth's magnetic field an astronaut could receive approximately a 7,000rem dose through their space suit. Which is around 7 or 8x the fatal acute dose.
  17. ghrit

    ghrit Bad company Administrator Founding Member

    As it happens, concrete is not at all too bad a shield for neutron radiation. Water is better for a couple technical reasons for neutron, but neither are as effective for gamma as lead. Lead, concrete and water are all very effective for alpha and beta, one could say as close to perfect as needed.

    FWIW, spent fuel pools use water more for cooling than for shielding, simply because decay heat continues for "quite a while" after the fuel elements are removed from the core. As a general statement, decay heat is from activated elements that are emitting particles (alpha and beta, mostly) that are contained within the cladding, thus no separate shielding is needed as long as the heat is removed. Reduced and oversimplified as an aid to understanding something of the principles, it can be said that the decay heat is mostly friction of particles rubbing one another. That "frictional" heating MUST be removed or the cladding could overheat and rupture and release radioactive materials into the water.

    Now, I have to say that the science of shielding is not high school physics. In fact, it's a bit of an esoteric study all on its own, after basic college level physics have been completed OR dot mil has seen to it that some service members got a good grounding. As a practical matter, shielding is the last of three protective measures when it comes to radiation. Time is first, don't go near a source until it has time enough to decay. Distance, just get the hell away with time telling you how long you have. Shielding is the last item. TDS was rammed at us, left, right, and center, for the entire time in the business. (Mix and match as needed for the application.)

    For the sake of the curious, you can take 10 half lives as the time until an isotope has decayed to background. Google will find you a periodic table of elements, from which you can pick your bugaboo isotope and figure out how long you need to stay away. That'll tell you that plutonium is going to take a while, and don't forget to factor in the time for the daughter isotopes ----
    Last edited: Feb 11, 2017
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  18. oil pan 4

    oil pan 4 Monkey+++

    Yeah all that raw nuclear waste puts off something like 1% of its rated power it made while it was in in production as decay heat.
    If cooling water flow stops flowing we're all screwed.
    The problem is the US hasn't recycled any nuclear waste since like 2002.
    That's bad because if you are exposed to a single fuel pellet of raw waste from 50 feet away for 5 seconds, you're dead.
    It needs to be recycled and not just disposed of.
  19. ghrit

    ghrit Bad company Administrator Founding Member

    That should be fact checked. Fuel pins are routinely transferred from the spent fuel pools to casks in the open with operators in fairly exposed and close proximity (so they could see the handling gear.) At least that was true back in the day, and resulted in no over exposure that I know of. That said, the operations have been refined (last I heard) to do the transfers in the wet, then draining the transfer casks.

    See also -

    And -
    NRC: Spent Fuel Storage in Pools and Dry Casks - Key Points and Questions & Answers
    Last edited: Feb 11, 2017
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  20. arleigh

    arleigh Goophy monkey

    It is my experience that though one drop of rain may not drown you, the continuous drops can.
    Radiation in small doses "continually" does serious damage, and that is the issue i'm concerned with .
    People poo poo Fukushima and the contamination continuing to fall into the ocean .
    If it were a single spill, the ocean could absorb it, but it is not a single spill , it is still going on. we are enduring the results every day along the coast here, and world wide for that matter .
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