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OCD and Fear of Radiation Contamination

  1. May 13, 2014 #1
    I've had to work with p33 and cesium-137 for a few of my labs for classes and for the past few weeks I can't seem to get myself to stop worrying about contamination.

    It seems irrational but I'm wondering exactly how dangerous both types are?
    Thanks for your time
    Last edited: May 13, 2014
  2. jcsd
  3. May 13, 2014 #2


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    If you have access to a Geiger counter, use it, get some rare, meaningless clicking and see it as confirmation nothing happened.
    If the sources were weak, calculate the worst-case radiation dose, it is probably below a dangerous value.

    Or just have a look at the sources to make sure they are still intact - for labs, I guess they were shielded, so the surface does not have radioactive isotopes anyway.
  4. May 13, 2014 #3


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    Well, I wouldn't recommend that you put any of these elements on your corn flakes for breakfast, but a more important question, perhaps, is what sort of radiation safety protocols were you under while working with these materials? Were you wearing any sort of dosimeter badges to see if you had been exposed to too much radiation? Did you wear special protective gear/use special devices to handle this material while working with it? Did you have to undergo any decontamination procedures when you were done handling them?
  5. May 13, 2014 #4
    With p33 there were plexiglass shields and we wore latex gloves when working with it. We also had dosimeter badges. With cesium-137 we didn't have anything and were told not to touch it ourselves and had the TA physically handle it since we were just measuring decay rates. We had geiger counters for both and didn't undergo any decontamination procedures afterwards for either
  6. May 13, 2014 #5


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    I would imagine that they are sealed sources. I would expect HP staff to do swipes to ensure no surface contamination.

    I expect that one quite free of contamination.

    I handled many sources during my lab courses as an undergraduate and graduate student. I also handled neutron and strong gamma sources, and in one case work with a neutron beam. Finally, I've manually handled enriched fuel pellets (I wore latex gloves). After nearly 40 years, I don't have any indication of contamination or effects from exposure to radiation.
  7. May 14, 2014 #6

    jim hardy

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    Did you "frisk" your hands afterward?
    "Frisk" is the jargon for hold your hands near a geiger counter to make sure you didn't get any particles on them.

    To your question 'how dangerous are they ?',
    in addition to what Steamking wrote above i'll add this. (i assume you've not been through radiation training...)

    It would be abjectly negligent for whoever owns those sources to let students around them if they were dangerous. I cannot imagine it happening.

    The basic principle of radiation protection is "Time, Distance, Shielding".
    Presumably you weren't around the sources very long. It takes time to accumulate measurable dose.

    Presumably you left them there and didn't take them home. Distance.

    Presumably they were stored in some sort of container. Aluminum foil will stop Alpha and Beta rays. So will a few feet of air or some plexiglass. Shielding. Your P33 is a beta emitter .

    I had a personal rule of thumb that was reassuring to me.
    Ionizing radiation events happen individually, at molecular level. Geiger counters respond to individual events . So they're quite sensitive.
    It takes an awful lot of individual events to add up to bodily harm.
    Radiation meters for high intensity fields do not respond to individual events, they respond to the rate of energy being deposited in whatever the detector is made from. Better ones use detector material that mimics live tissue. They don't click, they read out on a DC meter.

    So my rule of thumb was - if i can read it with a geiger counter it's probably not enough to worry about. A genuine radiologist will tell you that's not strictly true, ....
    but -
    That you had dosimiters tells me you were under the auspices of responsible people.
    That you used geiger counters tells me you weren't measuring very "hot" sources .

    I would not worry if my grandchildren did something like that for their scout merit badges.

    So I think you need not worry about your experiment, either.

    Here's a list of commonly used radioisotopes:
    https://www.idph.state.ia.us/eh/common/pdf/radiological_health/radioisotopes.pdf [Broken]

    Like Asronuc i worked (for decades) around neutrons and gamma rays. Still hanging in there !

    old jim
    Last edited by a moderator: May 6, 2017
  8. Oct 20, 2016 #7
    I too suffer from horrendous OCD about radiation-but only contamination. X-rays don't bother me at all, and neither does sunlight or eating bananas for that matter. For the last few years, my crazy thought has been about a nuclear gauge (like this) touching me or more specifically landing on my lap. I have thrown out countless pairs of jeans and pants for fear of contamination. deep down I know it is complete non-sense, but my disorder wont allow me to let it go. I am constantly worried that one of these devices has come into contact with my lap to the point that my skin feels like it is burning but it is not.

    Out of curiosity-what might happen if one of these devices did in fact touch my lap or come into contact with my clothing? (I do not work with these or any other radioactive stuff so please don't worry) I know it is my crazy OCD but I just cannot stop worrying about it. Would I need to throw the clothes out as I have been doing (even though probably only imagined and not necessary)? Is this the stupidest thing ever to worry about?
  9. Oct 20, 2016 #8

    jim hardy

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    You'd absorb a little bit of radiation, the amount in proportion to how long you held the gizmo in your lap. Clearly , from the picture you posted, the gizmo is safe enough to be handled. The source inside it is sealed up so it won't transfer its radioactive contents to your clothes. The ones i've seen come with a heavy lead shielded carrying case that the source goes back into after each use.

    The radiation it emits is not like germs that stick to clothes or skin, it's more like light present only in proximity to the source.

    Not unless the source was physically broken open so its contents could leak out.
    Do you also obsess over dental and medical X-rays ?

    Best cure for fear of the unknown is to make the subject no longer unknown.

    for starters I suggest looking up the terms
    Roentgen Equivalent Man

    Boring Anecdote
    Realize also that today's radiation detectors are incredibly sensitive.
    I worked in a nuke plant. Every workday we exited the gate via walk-through radiation scanners. After my heart stress tests where the heart doctors inject a mildly radioactive muscle tracer Technicium, i set off those scanners when i got within fifty feet of the exit gate. So i had to wait until after shift change so as to not disrupt orderly exit of my co-workers. I felt perfectly normal , no burning no sickness no fatigue. Our health physics guy measured me and said i was less than 2 millirems per hour on contact, easily measured but far from dangerous. A few thousand times that would be dangerous.
    Point being living tissue is far less sensitive to radiation than the fearmongers would have you believe. Anything dangerous to humans will overload most radiation detectors. That i pegged our exit portal scanners is a testament to their sensitivity.

    So if you're working around those pavement thickness gauges just respect the source they use.
    As with any other creature respect and avoid its bite. Keep it in its cage when not in use .

    best cure for fear is understanding. Do some reading.

    ... my two cents (and that's overpriced)

    old jim
  10. Oct 20, 2016 #9


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    Nothing. The IAEA has regulations about allowed radiation levels of materials in containers. The highest class (page 19) has 2000µSv/h at the surface, or 35µSv if you have it on your lap for a minute. An airplane flight leads to higher doses, and the highest class is rare anyway. There is no contamination because the probes are always sealed.
  11. Oct 20, 2016 #10
    thanks for that. it looks like those figures are if the gauge is in its case. Would it be considerably more if the gauge touched me outside of the shipping container? And I know the sources are encapsulated but why then are leak tests frequently performed? It does seem possible that if one of these gauges did land on my lap somehow that there is the possibility of contamination and getting radiation poisoning. (I know this sounds crazy).
  12. Oct 20, 2016 #11


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    No. The containers are not very good shields against gamma rays or neutrons.
    To make sure they are still encapsulated. I have worked with radioactive materials, and I never met anyone who ever had any source which was not properly encapsulated. They are still tested, just to be sure.
    The probability is zero. Radiation poisoning is a short-term result. You either get it within a few days, or not at all.

    You could eat many sources without harm. Highly active sources are extremely rare, and unless you are a trained radiation worker, you never even get close to them.
  13. Oct 24, 2016 #12
    I used to work in Radiation Protection and now work in nuclear chemistry in a nuclear plant. If you're referring to detectors or dosimeters you have zero reason to worry, almost all portable instruments for human use like the one pictured don't contain a source, just a detector and are calibrated elsewhere or by trained personnel who are certified in calibrating and handling the instruments and sources. Not to mention exposure and contamination aren't the same thing. Remote monitoring equipment, like those mounted inside reactor unit vents or areas that can't or shouldn't be easily accessed, have built in sources but are encased in shielding to protect the detectors from incident, scattered and background radiation. If you do come into contact with a source, it or the container it's in would have to be damaged to contaminate you, otherwise you'll just receive dose exposure and not contamination. You can hold a fuel pellet or nuclear bomb core and not be contaminated, you'll be heavily exposed but not necessarily contaminated. I have never worn protective clothing when handling monitors, hell I wear two monitors around my neck almost all day, a TLD and an Electronic dosimeter. If you're still uncomfortable wear nurses scrubs and nitrile or vinyl gloves and discard them when you're done, but I promise you don't need them.
  14. Oct 24, 2016 #13


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    Nuclear weapons are usually quite pure and contain mainly alpha emitters - I would not expect a dangerous exposure even if you hold them in your hands (something many people did in the past - the deaths there came from brief moments of criticality).
  15. Nov 8, 2016 #14
    A day in the life of OCD... Getting out of my car this morning at my local train station, I think one of those nuclear moisture gauges for road construction possibly touched my lap as I exited my vehicle. (I understand this is highly unlikely and most likely did not in fact happen, but I cannot "shake" the thought. That's how crazy OCD is.) Now my day has consisted of feeling contaminated by radiation or radioactive material. I cannot focus on work, and simply cannot wait to go home, throw the clothes I am wearing out and take a shower and scrub. Hopefully I am not sterile now. lol.
    So strange that this idea has become the center of my contamination obsessions as I am not afraid of x-rays or cat scans and have had plenty of those.
    Sorry to post this here, but I have found this forum to be somewhat therapeutic when it comes to these crazy fears. Hope everyone is having a great day =)
  16. Nov 8, 2016 #15

    jim hardy

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    Best cure for irrational fear is to learn something about it.
    Do you tinker with electronics at all ?

    Here's a clever hobbyist Geiger Counter , home made.

  17. Nov 9, 2016 #16


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    If those devices had a habit of shedding parts of their source they would be illegal to use. I think it is safe to assume that even severe abuse outside of deliberately trying to get at the radioisotopes will not release contamination.

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