- I have just attempted to decipher the nonsensical 'energy
ranges' Radnet now uses. Basically, it cannot be done. The ranges mean
nothing. In addition, they are apparently calibrated to show 'normal'
background as a zero baseline. If the 'normal' background doubles, they
can just reset it to zero.
- There is no number we can multiply Ci and Bq (measures
of CPM) by to get R or rad and Sv or Gy. Different isotopes emit different
energy gammas and some emit more than one gamma. At the same rate of emission
or decay, an isotope that emits more and higher energy gammas will give
a higher rem/hr or Sv/hr. Ci and Bq are based on dpm/sec (dps).
- The same emission rate (dps) for Cs-137 and Co-60. Co-60
will give you a higher dose-rate and dose because it emits two gammas above
1000 keV where Cs-137 emits only 1 gamma at 661.8 keV. Obviously Co-60
is emitting more electromagnetic energy per decay than Cs-137 which will
give one a higher dose-rate in R/hr or Sv/hr.
- In addition, the dose and dose-rate vary with the distance
from the source. We cannot convert from Ci and Bq to R, rem or rad and
Sv or Gy. A complicated calculation on an isotope by isotope and a distance
by distance basis is required.
- We can't know the types of isotopes because we cannot
qualify them. If we did, we could use this:
- Even then, the type of detector makes a difference. The
RADNET guys say their manual states "Experts have to look at the various
ranges for trends in order to determine specific isotopes." Which
- The only thing I managed to get was "In the old
system, the five energy ranges were 200 - 500, 500 - 1100, 1100 - 1590,
1590 - 2000, and 2000 - 3000 KeV. New system overlaps each of the five
and the first is numbered 2. Ranges 2-6 are not unusual to see between
500 and 5000 and are typically transient atmospheric phenomena, but can
be from local radioactive elements. Ranges 7-10 are from typically cosmic
in nature and high levels are generated from GRB's."
- Unfortunately, for our purposes, that still means nothing. At
this point I have no idea of the purpose of RADNET.
- Earthquake Data Also Vanishing
- Yesterday you could link here: http://www.fnet.bosai.go.jp/waveform/view.php?plot=
- from the 'Japan' link at the bottom of the USGS Earthquake
Hazards program page: http://earthquake.usgs.gov/earthquakes
- Today, that link is gone. Several earthquakes are now
shown for East Honshu that were not shown at all yesterday. I commented
that Honshu stopped having earthquakes on at least two blogs. It seems
they were simply not being reported correctly.
- The magnitude 6.x earthquakes have given way to magnitude
5.x earthquakes over the past couple of days. I doubt that the energy
has dissipated. I suspect that it is accumulating.