stock here. I was getting a ton of hits from this site where I copied this information.
Its a pretty good writeup, BUT, kind of more of a sales pitch than actionable information.
I did a writeup shortly after Fukushima, and came up with an Actionable Table that was not available anywhere in the world.
That Table is HERE, please review, print, keep it with your Geiger. Spread the word far and wide. Several others have copied it nearly verbatim, but I sure appreciate the attribution.
An aside --- Medical Products recalled due to cancer risk.
https://www.wcvb.com/article/more-blood-pressure-meds-recalled-for-cancer-risk/26591643
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Top 7 Geiger Counters & How they work
This article was written by Dave Robertson (see bio
below). I asked him to write this knowing that I had little knowledge of
Geiger Counters, but also knowing that I really wanted you guys to get
solid basics and a decent comparison. I consider a Geiger counter a
luxury item, unless you need it.
Please keep in mind some of the recent (early 2016) articles in the news
about documents stating that large amounts of radioactive material may
have disappeared in the middle east. Of course we can’t say for sure
what the who and why are, but we can say that dirty bombs are a very low
tech way of causing large disruption once you have the material. Please
keep in mind that you may need a Geiger counter to determine how
radioactive your water supply or food might be. Even oceans can carry
radioactive material as we saw from the recent nuclear disaster in
Japan. Please don’t hesitate to add a Geiger counter or two to your
bugout gear. John
What do they do?
A geiger counter is a device that detects radioactivity, also known
as ionizing radiation. Nearly all geiger counters detect x-rays and
gamma rays, the two strongest and most dangerous types of radiation.
X-rays can travel long distances and can pass through most any material
except lead. Gamma rays, though usually not as strong as x-rays, still
require thick shields of lead or concrete to stop them. Both are very
dangerous to the health of humans. Some geiger detectors also detect
alpha and beta radiation. These types of radiation consist of particles
produced by the decay of certain unstable atoms. These types of
particles can only travel a short distance through the air and both can
be stopped by heavy clothing or thick cardboard. Alpha particles can be
dangerous, however, if ingested or inhaled.
Each geiger counter contains a small device called a Geiger-Muller
sensor. It’s the thing that actually senses radiation. A pocket style
geiger counter is roughly the size of a cell phone and stows easily in a
pocket. You could walk down a city street, checking radiation levels as
you go and nobody would be alarmed. The other type of geiger counter
has an external wand and the sensor is contained in the wand. If you’re
checking the radiation of specific objects, you’ll need to get the
sensor close whether it’s the wand or the pocket unit itself. Most
geiger counters show radiation levels with a visual readout and with an
audible signal, a tick or click that sounds for each particle detected.
The more noise the detector makes, the higher the concentration of
radiation found. You’ve probably seen movies where characters use a
geiger counter. A few random clicks might be acceptable, but when there
is radiation danger the counter sounds like a radio emitting heavy
static. Time to hightail it out of there.
Why do I need one? (Prepping for SHTF, TEOTWAWKI)
If a nuclear facility has a meltdown or a “containment problem”,
you’ll want to know how it affects you. Also nuclear material is
routinely mined, transported, and stored. What happens when there’s an
accident? Are we always informed, or do problems happen without our
knowledge? The authorities may be able to hide these problems, but if
you have a geiger counter you can still be aware of the danger. Let’s
say you find yourself in a situation where you need to bug out. Are
there old uranium mines in the area? Recent hazardous spills? A geiger
counter can help you stick to areas with lower radiation. It can also be
used to test food, fish, and other game for high radiation levels. Even
if there is no disaster situation, a geiger counter can be very useful.
You may have items in your home that emit or contain low levels of
radiation. Did you know that some antique pottery and furniture is
coated with a radioactive glaze? Glow in the dark watch dials are
usually slightly irradiated, smoke detectors contain a radioactive
material called Americum (a tiny amount, but still). Are there unknown
sources of radiation near your home or safe place? Get a geiger counter
and check.
‘Normal” Radiation and what in the world is a microsievert?
People who measure radiation use various units of measurement. One is
microsieverts/hour which is often shown as uSv/hr. You’ll also see it
with a long tail on the left side of the “u”. That’s the technical
symbol, but for those of us who can’t figure out how to make that fancy
symbol on our keyboards, we just use uSv/hr. Sometimes you’ll see
mcSv/hour which also stands for microsieverts/hour.
So how many microsieverts/hour is “normal”. Well, that’s a bit of a
problem. No one seems to agree on what’s normal and “acceptable levels”
as defined by the US government have changed several times over the
years. But here’s one way to look at it. The average American is exposed
to about 3600 microsieverts a year. That works out to about 10 per day,
or .41 uSv/hour. If your geiger counter is showing .25 to .5 uSv/hr you
know you’re pretty close to normal. Again, we all are receiving about
10 microsieverts per day. Consider that normal background radiation. For
perspective, A dental x-ray adds 5 microsieverts. A flight from NY to
LA exposes you to an additional 40 microsieverts. Spending one hour near
the Chernobyl nuclear plant in 2010 would have netted you 6 sieverts,
which is 6,000 microsieverts! Who knows what the level could be in a
Teotwawki situation?
Another unit of measurement is milli-Roentgens/hour shown as mR/hr. In
the US, Roentgens used to be the standard unit, but that is quickly
being replaced by microsieverts which is the standard in much of the
rest of the world. Most of the detectors you’ll find today still can be
set to microsieverts or milli-Roentgens. Also, many radiation detectors
will have audible, visual, or vibrational alarms that will go off when
radiation levels are high. With most detectors you can set the level
where you think “high” begins. 1.0 uSv/hour is considered by some to be
“unsafe”, while 1.2 or more is considered “dangerous’. Again, there is
no universal agreement on what constitutes unsafe or dangerous.
Geiger Counters Compared
Many of the most common radiation detectors I found are from four
main companies: GQ, Radex, Soeks, and GCA. They are listed in order of
price. The more expensive ones tend to have more functions and claim to
be more sensitive and more accurate. All are calibrated from the factory
and should be accurate out of the box. Some of the online reviews are
helpful in determining the reliability and functionality of different
units.
$99 – rating average on Amazon 4.2 stars (100 reviews)
View on Amazon
This is a pocket sized geiger counter that has both audible and
visual signals for detected radiation levels. Visual LED readouts show
radiation detected in both microsieverts and milli-Roentgens. The device
can continually monitor radiation levels and store the data in its
internal memory. It can also be connected to a PC via the device’s USB
port so that data can be stored and analyzed. It is powered by a
rechargeable internal battery which can be charged using the supplied
wall adapter. Continuous data monitoring is possible using the wall
charger. An included disk provides software for use with a PC.
$147 -rating average on Amazon = 4.5 stars (84 reviews)
View on Amazon
Pocket sized and operating on AAA batteries, the Radex is for use
indoors, outdoors, and with objects. It has audio and visual readouts
(in microsieverts and Roentgens) with audio and vibration alarms. The
company claims the unit has been tested by the Japanese Consumer
Protection Agency and it is backed by a one year warranty.
$174 -rating average on Amazon = 4.7 stars (17 reviews)
View on Amazon
The Soeks Defender portable pocket size radiation detector includes
3.5 inch military grade Geiger Muller Tube SBM 20-1 that is the standard
for surveying areas for potentially harmful ionizing radiation levels
and for detecting radioactive contamination of food, packages, supplies,
equipment and people after SHTF. The color display shows radioactivity
levels in graphs and numbers and changes color to red for Dangerous
Levels of radiation (greater than 1.2 uSv/hr) ,green for Normal
radiation background measured less than 0.4 uSv/hr, yellow for HIGH
radiation background 0.4-1.2 uSv/hr. Users can scroll through 3 menu
categories: Device Settings, Measure and Radiation Dose; Users can
easily set a threshold value, access Screen settings such as Brightness,
Themes (4 possible), Off time, Sound (keypad, sensor and dose sound for
the alarms and volume) Accumulated Dose. Accumulation process of
radioactive dose begins after the device is switched ON and goes on
permanently until device is switched off, regardless of current mode.
When you turn it back ON, accumulation process continues; Battery life
is 10 hours of continuos use batteries rechargeable through included USB
cable or charger; Alarm sounds an audible alert when the measured
radiation level exceeds safe level and can be turned off in settings.
Designed by SOEKS and manufactured in Russia,
$260 – rating average on Amazon = 4.4 stars (17 reviews)
View on Amazon
So what’s the difference between this unit and Radex’s lower cost
RD1503? Whereas all the detectors mentioned so far have one
Geiger-Muller sensor (that’s the thing that senses the radiation) this
unit has two sensors. Like the other Radex unit, it has the same simple
design with three buttons, LED display, and similar functions such as
alarms, backlit display, and so on. It is covered by a one year
(limited) warranty.
$288 – rating average on Amazon =4.0 (13 reviews)
View on Amazon
This pocket size geiger counter is able to continuously monitor the
radiation environment up to 999 days and work continuously up to 700
hours and alert a user if the preset dose and dose rate thresholds are
exceeded. It measures bets, gamma, and x-ray radiation. This unit has
two Geiger-Muller sensors, audible and visual alarms, and a color
display. it has a USB port for connection to a PC and comes with 2
rechargeable batteries, an AC adaptor, and USB cable. It is covered by a
two year warranty.
$350 – rating average on Amazon = 4 stars (22 reviews)
View on Amazon
The GCA-07W is a professional quality monitor that can be certified
accurate by the NCR, an independent licensing lab in the U.S. This
radiation detector uses an external wand. The wand actually contains the
Geiger-Muller sensor. This wand can then be more accurately aimed at
radiation sources. Also, if you wish to monitor the radiation outdoors,
you could project the wand outside and stay in relative safety indoors.
It measures alpha, beta, x-ray, and gamma radiation. The Liquid Crystal
Display shows levels in milli-Roentgens/hour or micro-sieverts/hour. The
unit has both audio and visual indicators, a USB port to connect to a
PC, plus headphone and power jacks. It uses a 9V battery for mobile
operation but can be used with a wall adapter (included).
$595 – rating average on Amazon = 4.5 stars (33 reviews)
View on Amazon
The Mazur Instruments unit detects alpha, beta, gamma, and x-ray
radiation. The two-line, alphanumeric display supports both English and
Japanese languagest. The display is backlit to support low-light
conditions. Using only one key, users can scroll through several screens
that display present, average, maximum and minimum measurements in
uR/hr, mR/hr, uSv/hr, Counts per Second (CPS) or Counts per Minute
(CPM). The PRM-9000 instrument not only records the maximum radiation
measured, but also displays the time and date at which the maximum
occurred. Battery life is over 4-years under normal conditions from a
single 9-volt lithium battery. Standard alkaline 9-volt batteries
available everywhere provide over 2-years of life under normal
conditions. With over 100K bytes of data logging memory included, the
PRM-9000 can autonomously store up to 91,466 minutes of time-stamped
measurements. These measurements can then be uploaded to a PC in CSV
format for analysis. A user-settable dose rate alarm sounds an audible
alert when the measured radiation level exceeds that of the alarm level
setting. Designed by Mazur Instruments and manufactured in the USA, the
PRM-9000 includes abundant I/O options including support for headphones,
external speakers, external power and PC/Mac USB data exchange
(requires optional 3.5mm to USB adapter cable).
Do the DEMs actually have some game, or are they just talking a big story?
Do the DEMs actually have some game, or are they just talking a big story?
