What Should I Do?

Quick Primer on Contamination Control Measures

Thursday, March 17, 2011, 6:02 PM

This short primer was provided by PeakProsperity.com member Dogs_In_A_Pile in the comments to our ongoing post covering the developments in Japan. We are featuring it here given the many questions readers are asking on this topic and the importance at this time of clearly understanding risks we do (and don't) face. It is based on his expertise developed during his military service on nuclear-powered submarines. 

Radiation and contamination are used interchangeably and they are not the same thing, nor are treatment methods.  You can receive radiation exposure and not need any contamination control, and you can become contaminated and not need treatment for exposure to radiation.  NOTE - I am not saying that if you get contaminated you won't receive any radiation exposure, because you will.  What I am saying is that you may be contaminated with such a low level of contaminated particles that there will be no need for radiation exposure treatments.  The difference is both subtle and vast. 

Here is a quick primer on contamination control measures.

  1. Know what the radionuclide is - Is it particulate or is it a gas?  There are some radionuclides that exist as a radioactive gas that decay to a radioactive particulate.  Just because a gas dissipates, it doesn't mean you are safe if you are exposed to an area of particulate that may be stirred up and ingested.
  2. Absent knowledge of the specific radionuclide, don't expose yourself to it if you don't have to.  This may seem like stating the obvious, but it's not.  Exposing yourself to contamination to treat an injured person or remove an injured person is probably the right call.  Exposing yourself to contamination to reach an injured pet is probably not the right call.  That said, in violation of my own advice, I wouldn't hesitate to go get my 12-year-old golden retriever.
  3. If you do have to expose yourself to radioactive contamination, there are two things to differentiate:
    • General radiation level.  You can minimize exposure to radiation by utilizing the following, preferably in combination:
      • Time:  Minimize the time exposed.  Do what you need to do as rapidly as it can be done safely and effectively.
      • Distance:  Maximize the distance between the radiation source and yourself.  Exposure falls off as an inverse squared function.  A 10 millrem/hr source measured at 2 feet will drop to 2.5 mr/hr at 4 feet.  (http://www.wright.edu/admin/ehs/documents/EquationsforRadiationSafety.pdf)
      • Shielding:  Utilize whatever you can to put between you and the source.  Concrete, lead, steel, poly sheeting, or poly blocks are all effective to varying degrees against the different types of radiation you may encounter.
    • Contamination.  Contamination is the "dirt;" radiation is the energy coming off the dirt.
      • Breathing protection:  It may be suspended as particulates in the air if it is fine enough.  A simple mask that provides any degree of mechanical filtration is better than nothing.  Sealed forced air is best.  If you can see suspended motes, really think twice about entering the area without breathing protection.  You will exhale about 75-90% of inhaled particulate matter.  You run into trouble when the specific radionuclide is preferentially concentrated in the body, like I-131 is.
      • Protection against skin contamination:  Long-sleeved shirts, long pants, shoes, socks, a hood, gloves, etc.  Try to cover all exposed skin to the maximum extent possible.  Assume that the clothing is contaminated, and dispose of it after you have left the area that is potentially contaminated.  If you can, construct a staging area at the boundary of the contaminated area so you can strip down and step into the clean area and leave your contaminated clothing behind.  Important safety tip - make sure you are wearing undergarments.  (Unless you are either immodest or a show-off Surprised).
      • If you do have skin contamination or suspect you have skin contamination, there are several methods of removing it safely:
        • You can use a tape press.  Duct tape or packing tape will work.  Press the sticky side on to the affected area with enough force to contact the material, but light enough to not risk grinding it into the skin.  Discard the used tape, as it will be contaminated.
        • Wash and rinse with soap and water.  Use lukewarm water.  Hot water opens the pores and risk trapping the particulate inside.  Cold water closes the pores and will trap the particles.  A mild abrasive is okay to use if you don't grind it into your skin.  If you suspect the particulate to be trapped in an abrasion or a cut, scrub vigorously, as it is already stuck in your skin.   A little bleeding from a mild abrasion (like a skinned elbow or knee) isn't bad since the blood flow will in some cases help push the particulate away from the skin, where it can be rinsed away.  The risk is pushing it down into a large enough blood vessel or capillary that it could get picked up by your circulatory system, but the risk is low if you are careful.  Collect the rinse water, since it will be contaminated, and keep it separated.
        • If you have an open wound with serious bleeding and you suspect there is contamination present, you must treat the wound first.  Sealing some amount of contamination in a wound to stabilize severe bleeding for further treatment is far better than bleeding to death.  Collect and dispose of the medical waste assuming that it is contaminated.
        • Skin contamination in and of itself is not a big deal if the associated dose rate is relatively low and you remove it as quickly as possible.

Regarding the unfolding situation in Japan,, it is important to understand the real nature of the risk associated with a release of a radioactive plume from steam venting, a fire or some combination of both.  Understand the radionuclide composition of the plume and the type of radiation associated with each.  Alpha emitters, beta emitters, gamma emitters, and neutron emitters are all handled (figuratively) differently, and each poses different levels of risk. 

  • Alpha:  External alpha contamination isn't that big of a deal, since the particles won't penetrate dead skin.  Internal alpha contamination is a big risk - an alpha particle is a helium nucleus (4He2) and it is big and heavy.  Whatever it hits in a cell's nucleus, it wrecks. 
  • Beta:  External beta contamination is not much of a risk (in reasonable quantities), since betas are easily shielded by clothing.  Internal beta contamination presents varying degrees of risk depending on the radionuclide, which defines half-life and energy level of the beta decay.  Some radionuclides decay rapidly and may pose a very minimal risk.  Longer half-lives increase the risk.  Some radionuclides are preferentially concentrated and the risk increases.  Knowledge of the isotope is key.
  • Gamma:  High energy and penetrating.  There is not much you can do except utilize the concept of Time/Distance/Shielding.  You want to minimize your exposure to a gamma emitter, regardless of whether it is from contamination or a fixed source.
  • Neutron:  High energy, very penetrating, very damaging.  You really don't want to be exposed to neutron radiation, regardless of whether it is contamination or a radiation source.

I hope this helps.  I'm sure I forgot something, so if there are any questions don't hesitate to ask by commenting below.

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16 Comments

pinecarr's picture
pinecarr
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Nice clear explanation,

Nice clear explanation, DIAP!!  It's kind of impressive to see people's expertise in different areas come out here, when the situation calls for it.

Our hearts are with our friends in Japan!

VeganD's picture
VeganD
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As stupid as this sounds, it

As stupid as this sounds, it never occurred to me that you could wash off the contamination.  That info alone is worth the price of admission :)

Thank you

SagerXX's picture
SagerXX
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As always...

...you rock, DIAP!  Mucho thanks for the primer -- it'll be heading out to various folks on the Left Coast, which just may stop the run on nori from San Diego to Vancouver...

Viva -- Sager

gmeader3's picture
gmeader3
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What is the likely radionuclide composition of Fukushima plume?

"Understand the radionuclide composition of the Fukushima plume and the type of radiation associated with each. "

What is the likely radionuclide composition of material likely to arrive on the continental USA?

Where can we get this info?

SagerXX's picture
SagerXX
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xenon-133

The Beeb's live blog has this nugget:

Quote:
"Miniscule quantities of the radioactive isotope xenon-133" were picked up by a monitor in Sacramento.

http://www.bbc.co.uk/news/world-middle-east-12307698

Dogs_In_A_Pile's picture
Dogs_In_A_Pile
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Probable plume contents you should plan for....

gmeader3 wrote:

"Understand the radionuclide composition of the Fukushima plume and the type of radiation associated with each. "

What is the likely radionuclide composition of material likely to arrive on the continental USA?

Where can we get this info?

Cesium 137 and iodine 131 will be the dominant radionuclides; tellurium may also have been aerosolized and spread.  Depending on how rapid the transport is you may see detectable levels of radioactive xenon and krypton.  There may also be some very finely suspended zirconium, niobium and lanthanum as well as transuranic and minor actinide isotopes.

Cs-137 has already been confirmed in the Aleutians and reported in California.  The EPA and DOE have increased their monitoring in Alaska, California, Oregon and Washington, but I have not been able to find any websites where sample results have been made available to the public.  So we are hostage to the efficiency of information dissemination from the EPA and DOE.  Personally, I'd rather have actual measurements and data and do the math myself than to have a summary report that says everything is okay. 

As things currently stand with regards to conditions at the Fukushima accident site, the current assessment of negligible levels and very low risk to the west coast is accurate.  But that is entirely dependent on how things play out in Japan and people need to be prepared in the event things degrade.  Your response plan should be flexible and responsive enough in the event the actual events don't quite play out like the models predict they would.

Dogs_In_A_Pile's picture
Dogs_In_A_Pile
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Xe-133....Fission product or medical?

SagerXX wrote:

The Beeb's live blog has this nugget:

Quote:
"Miniscule quantities of the radioactive isotope xenon-133" were picked up by a monitor in Sacramento.

http://www.bbc.co.uk/news/world-middle-east-12307698

Sager, if this is confirmed this could be fairly significant in that it all but confirms the suspicion that fuel damage has occurred and radioactive contamination from inside the core and/or primary containment boundary has escaped into the environment. 

Be advised that Xe-133 has medical diagnostic applications.  I'm not saying that this report is false in that it is medical Xe-133 and not from a release in Japan, but it is an isolated report.  I'd feel better (in a bizzare sense of the word) if Xe-133 was being detected in other places outside of Sacremento.

Rector's picture
Rector
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I know its not even close to

I know its not even close to necessary at all at this time, but I think lots of folks may be trying to source KI as this unfolds.  Is anyone (DIAP?) able to speak to the type of event or trigger that would indicate taking KI?  I recently (prior to the event) bought seven 14 day doses of KI, plus some in liquid form for my infant daughter.  It came with a pretty lengthy instruction set, but I am unsure about identifying if radioactive iodine is present at all.

Any thoughts?  I have a radiation detector, but it doesn't tell me WHAT is in the air.

Again, I live in Texas and I am pretty sure that Japan won't result in any need for KI here, but if the worst happens and something blows into CA, send my a private message, and I can share what we have here if there is a need.

Rector

Dogs_In_A_Pile's picture
Dogs_In_A_Pile
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I-131 release and when to take KI....

Rector wrote:

I know its not even close to necessary at all at this time, but I think lots of folks may be trying to source KI as this unfolds.  Is anyone (DIAP?) able to speak to the type of event or trigger that would indicate taking KI?  I recently (prior to the event) bought seven 14 day doses of KI, plus some in liquid form for my infant daughter.  It came with a pretty lengthy instruction set, but I am unsure about identifying if radioactive iodine is present at all.

Any thoughts?  I have a radiation detector, but it doesn't tell me WHAT is in the air.

Again, I live in Texas and I am pretty sure that Japan won't result in any need for KI here, but if the worst happens and something blows into CA, send my a private message, and I can share what we have here if there is a need.

Rector

Rector -

Once I-131 was detected in the vicinity of Fukushima Daiichi, the people in the surrounding area needed to be ready to start taking KI.  I have no doubts the emergency response teams did.  If I was within 50 miles and couldn't leave the area, I would take KI.  I think you should have KI tablets on hand if you live within 50 miles of a nuclear power plant.  Chances are you will never need to take them, but they don't cost much and once purchased it's like an insurance policy.

I am looking for a good source for you to demonstrate how to determine the half life and therefore the radionuclide just using the radiation detector you have.  If you count your sample, wait 10 minutes, count again, you can start plotting a decay curve.  After several sample counts you can determine the radionuclide.  I'll follow up with a PM. 

thatchmo's picture
thatchmo
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contamination protection

Thanks Dogs, for all the great info.  Two questions:  If one had to go in a contaminated area or outside in a "fallout" situation, would rubber boots, a painter's TYVEK suit and hood and basic dust filter be decent protection?  Could they be reused after a wash down?  I'm thinking most of us have some of these things available.  Second question- If one were to completely tape up their windows on their house for protection,  any sugestion as how to provide adequate clean breathable air?   Not worrying, just wondering......Aloha, Steve.

Rector's picture
Rector
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Thanks

I can wait on the information.  You have more important stuff on your plate right now.  Keep up the good work, and I learned a lot from the podcast, Sir.

Rector

Bytesmiths's picture
Bytesmiths
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Here's our plan:

Dogs, I don't know if you've seen our radiation fallout plan. I'd appreciate any comments you might have.

I'm more concerned about our four pregnant goats than I am with ourselves. We can keep them inside on hay that's under-cover through term if we have to.

Bytesmiths's picture
Bytesmiths
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Start getting to know your counter NOW!

Rector wrote:
I have a radiation detector, but it doesn't tell me WHAT is in the air.

I'm assuming it's a Geiger-Müller counter. You want to have some practice with it before you need to use it!

I would start a logbook, so you can get a good feel for the extremes of your local background radiation. Do this indoors, but not in a basement, where it might be influenced by radon gas. (But do the basement test later, after you've established background levels! Best place is a crack in the floor, gap in the wall, or any other place that ground gasses might infiltrate.)

Ideally, you have a counter that records actual ionizing events, so you can average over at least ten minutes. Longer is better. Changes from minute to minute can be double or half the average rate, so don't get freaked out if all your counter can do is a simple "CPM" rate and you notice it double! (But if a 12-hour count doubles, you may have a problem.)

Try a few supposedly radioactive things, so you can get a feel. Some orange glazes are radioactive, as are some expensive camera lenses, tungsten welding electrodes, and camping lantern mantles. (Despite all the hype, I have NEVER been able to get an elevated reading from a banana! :-)

Environmental sampling is another matter. You need to either point the thing at a sizeable patch of ground that would pick up fallout, or you need to collect any fallout for later counting. The best is to multiply the effect of fallout by sucking air for long periods of time through a filter, which you can then sample. To be meaningful, you have to know the volume of air sampled -- the CFM rating of the fan should suffice for a ballpark estimate. I haven't gone that far yet.

Once you know you are getting high environmental (versus background) counts, you can try to discriminate for particle type. Put a clean sheet of paper between your sample and the counter. If that changes the count, you're getting alpha -- could be plutonium, or it could be local radon or thorium.

If the elevated count is the same with or without the paper, try counting the sample through a centimetre or two of any handy organic matter -- a thin book, a hunk of cheese, what have you. If that changes the count, you're getting beta -- could be iodine, caesium, strontium... or...

If the elevated count is the same no matter what you put in the way, do your background count again. There may be a coronal mass ejection or other solar event going on. If you're actually getting measurable gamma from the environment (versus background), then there's something really interesting going on...

Here's my current radiation log since the disaster.

Dogs_In_A_Pile's picture
Dogs_In_A_Pile
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Contamination plan..

Bytesmiths wrote:

Dogs, I don't know if you've seen our radiation fallout plan. I'd appreciate any comments you might have.

I'm more concerned about our four pregnant goats than I am with ourselves. We can keep them inside on hay that's under-cover through term if we have to.

Bytesmiths -

I gave you some feedback in one of the other related threads and am trying to track it down.

You do need to change the title to Radioactive Fallout Plan or Radioactive Contamination Plan.  Radiation is energy and doesn't "fall out", but the radioactive particulate contamination does.

Dogs_In_A_Pile's picture
Dogs_In_A_Pile
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Protective clothing....

thatchmo wrote:

Thanks Dogs, for all the great info.  Two questions:  If one had to go in a contaminated area or outside in a "fallout" situation, would rubber boots, a painter's TYVEK suit and hood and basic dust filter be decent protection?  Could they be reused after a wash down?  I'm thinking most of us have some of these things available.  Second question- If one were to completely tape up their windows on their house for protection,  any sugestion as how to provide adequate clean breathable air?   Not worrying, just wondering......Aloha, Steve.

thatchmo -

What you have described would be more than adequate protection for industrial level radiological maintenance so it would be a very conservative approach to anything we would expect to see here in the US.  I wouldn't reuse anything except the boots and I would replace the mask or filter element each time you went out.

And all of that is predicated on the levels being high enough to warrant protective gear like you have described.  If airborne contamination levels were that high, you have to determine if you really need to be in the area and if you really need to go outside.

I doubt you would be able to make your house completely airtight so replenishing oxygen wouldn't be a concern.  Again, if levels were that high that your house needed to be completely air tight to protect you, I'd leave the area until levels subsided.

Dogs_In_A_Pile's picture
Dogs_In_A_Pile
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Found it...

Bytesmiths wrote:

Dogs, I don't know if you've seen our radiation fallout plan. I'd appreciate any comments you might have.

I'm more concerned about our four pregnant goats than I am with ourselves. We can keep them inside on hay that's under-cover through term if we have to.

Byte -

Found it......

http://www.peakprosperity.com/blog/alert-nuclear-economic-meltdown-in-progress?page=34#comments

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