Many readers have been sending me questions about radiation. One, from a reader in Los Angeles asked: “Mr. Rawles, Should I sleep in my basement for the next few weeks?”
Please don’t over-react, folks. I must state, forthrightly:
2.) In my opinion, the only significant risk to health here in CONUS  is possibly a chance that a bit of radioactive dust (with isotopes like Strontium-90 or Iodine-131) could end up deposited on pasture grasses and then subsequently become concentrated in cow or goat milk. (Remember what I posted the day after the first news report about the Fukushima reactors–about keeping powdered milk on hand? Stock up.)
3.) It won’t hurt to spend a little extra time washing fresh fruits and vegetables.
FWIW, I was stationed TDY in Stuttgart, Germany and was working a live intelligence mission with the 2d M.I. Battalion (AE) in the Spring of 1986. So I was down-wind when Chernobyl melted down . Been there, done that, got the isotopes. But I still ate a lot of white spargel , after Chernobyl. Coincidentally, we were bombing that same misanthropic dictator in Libya, then too. (Operation El Dorado Canyon .) History doesn’t repeat, but it often rhymes. So I think of early springtime as the season of Isotopes and Misanthropes.
Radiation, By The Numbers
Here are some useful numbers to file away in your Key References binder:
First, for those not familiar with the term Gray–the standard unit of measurement for radiation , and Sievert  (“Sv”–the now standard unit for an absorbed dose) that replaced REM (Roentgen Equivalent, Man), and RAD (Radiation Absorbed Dose). The metric SI system  makes a lot of sense, but some of us are still wet-wired for the Old School units of measurement. So for us Blast From The Past  era dinosaurs who still think in Roentgens, conversion from Grays to RADs are as follows:
1 Gy equals 100 rad
1 mGy equals 100 mrad
1 Sv equals 100 rem
1 mSv equals 100 mrem
And here is how Sievert numbers relate to REMs (found at Wikipedia):
1 Sv (Sievert) = 100 rem
1 mSv = 100 mrem = 0.1 rem
1 ?Sv = 0.1 mrem
1 rem = 0.01 Sv = 10 mSv
1 mrem = 0.00001 Sv = 0.01 mSv = 10 ?Sv
Now what does the foregoing really mean, in terms of human health? That is best visualized with a good summary chart , posted over at Next Big Future. Please take the time to look at that chart, and ponder it.
To Journalists, All Math is Fuzzy Math
I must warn you, folks; beware when watching news reports in the mainstream media that mention anything related to radiation. Keep in mind that most of these people are hired because they look handsome (or pneumatic) and have pleasant speaking voices, not for their technical knowledge.
Remember that in general journalists:
- Are typically mentally challenged when it comes to any sense of scale, (like 10x and 100x multiples). They find logarithmic scales particularly daunting.
- Are clueless when it comes to decay rates.
- Have little understanding of fallout deposition rates versus distance.
- Have no concept of distance and the inverse square law.
- Don’t understand the difference between alpha, beta, and gamma radiation. For instance, I once had a reporter ask me about “Tyvek gamma ray protective suits”. (No, I’m not making this up.)
- Have no sense of proportion when it comes to a momentary dose of radiation versus cumulative doses. (Back during the First Gulf War, I spent some time repeatedly trying to explain the difference between a dosimeter and a ratemeter, to a reporter. She kept saying: “But they look the same.” Then I had her look through each type pen, and she she exclaimed, “Oh, I see, they have different thingies, inside!”)
- Only vaguely “get it” when you try to explain concepts like inhaled dust versus isotopes deposited in thyroid glands, via the food chain. (And subsequent food or drink ingestion.)