Wednesday, March 16, 2011

Panic About Radiation

A lot of people do not realize that the risk of fallout is generally from events within a few hundred miles.  If someone had set of a nuclear weapon or two over Japan, I would not be freaking out about the radiation exposure from it.  And venting from these nuclear reactor failures?  Noise.  Worry more about the bananas, or being around a smoker.

My CD-710 radiation survey meter (calibrated last year) says that my exposure inside the house is 0.04 R/hr, or 40 mR/hr.  Here's a graph of someone's radiation exposure on a Texas vacation.  Because of my elevation (3820 feet), I'm not surprised that 40 mR/hr is at the high end of this.  (Elevation means less air protecting you from radiation.)  For all you nervous nellies out there--feel free to pull out your survey meters, and post what exposures you are getting.

UPDATE: A reader says that this should 40 microroentgens/hour--and from reading various sources, that sounds right.  Yet the dial on this survey meter clearly shows R/Hr.  I suppose that I better find a manual for this Jordan CD-710.

UPDATE 2: Here's the manual.  I'm reading this correctly.  Maybe I'm dead?  I have had this reading for many months.

UPDATE 3: Looking at the manual, it says to let the unit warm up for a minute or two before zeroing.  That may be the problem.  I'll try this again this evening, after letting it warm up.

UPDATE 4: I accidentally left it on all day--and when I rezeroed it, it now shows just barely above zero--something that is way down in the "not to worry" range.


  1. It might be good to remind ourselves that from 1945 to 1980 there were 521 atmospheric nuclear tests (plus 2 actual uses in Japan) with an estimated total nuclear yield of 480 Mt. Somehow, though, we managed to survive. I suspect that, in the unlikely event of a complete meltdown at the Japanese nuclear power plant, the result will be nowhere near as dire as the media would have us believe.

    I recall that Michael Crichton once wanted to write a novel on a planetary disaster, and thought that the Chernobyl accident would make a good basis for the novel. Upon investigating, he learned that the total number of deaths (immediate and long-term) was estimated to be less than 4,000. Compare this number to CNNs initial estimate of the number of long-term deaths: 3.5 million!

    The media is simply trying to attract viewers/readers by instilling fear in as many people as possible.

  2. I think that you mean 40 microR/hr. 40 mR/hr would be fatal over the long term. At your elevation, you would expect your dose to be about 400 mrem/year, or something much closer to 40 microrem/hr.

  3. Right next to the reactor compartment on my submarine you'd get about 1 mR/hr. If you've got 40 mR/hr, you'd be dead by now.

  4. I'm guessing you don't have the meter zero'd correctly.

  5. Looking at the manual, it says to let the unit warm up for a minute or two before zeroing. That may be the problem.

  6. Bubblehead is a ghost of his former self?