Radiation Detectors for Safety
Today, there are many concerns about nuclear radiation. Some of these include:
The GM-10 and GM-45 nuclear radiation detectors from Black Cat Systems are highly sensitive
devices, designed to allow you to easily monitor the ambient radiation levels in your location,
and quickly spot increases in local radiation levels, which may indicate accidents or attacks.
They are also useful scientific tools for the hobbyist and educator.
- Terrorism - spread of nuclear material by a "dirty bomb" or other means
- Nuclear accidents - Nuclear power plant releases, spills of transported nuclear material, etc.
- Naturally occuring radiation - radon, uranium, etc.
First, a brief discussion of the three types of ionizing radiation:
The GM-10 and GM-45 plug into your computer. The accompanying software (which runs on Windows
95/98/NT/2000/XP and Macintosh OS9 and OSX) displays the radiation readings from the unit,
as well as draws a graph, allowing you to monitor the change in radiation readings. Here's
an example graph:
The radiation readings will bounce up and down a little over time, due to the random nature
of radioactive decay, this is normal. But an actual change in local radiation levels will be
quite obvious, as a sudden jump in the reading. This could be due to a slightly radioactive
object suddenly appearing (such as a package in the mail), or due to radiation from the outside,
carried by the wind. Or, in the worst case, due to a nuclear spill, accident, or attack,
occuring nearby or upwind.
- Alpha Particles: Helium nuclei, generally emitted from heavy elements such as uranium and
thorium. Alpha particles only travel a few inches in the air, and can be stopped by a piece of
paper. Outside the body, they are mostly harmless, as outer layers of dead skin completely
block them. But if ingested, they can cause massive cellular and DNA damage, due to the fact
that they blast a very small area with very high levels of radiation.
- Beta Rays: Electrons moving at extremely high (often relativistic) speeds. They are more
penatrating than alpha particles. They can pass through light elements, such as paper and
aluminum (but only small thicknesses). Outside the body, they can cause damage to the eyes and
skin. Inside, they can cause major damage, much like alpha particles.
- Gamma Rays: Electromagnetic waves, similar to light, but at a much higher energy. X-rays
are identical to gamma rays. They are much more penetrating than alpha or beta radiations.
High energy gamma rays can pass through several inches of metal. They can cause damage to
all parts of the body, due to the ability to penetrate skin, tissues, bones, and organs.
Nuclear power plant monitoring - If you live in the vicinity of a nuclear power plant, you
can monitor the ambient radiation level in your home, and immediately detect an increase, which
could be caused by a leak of radioactive gases, or other emissions.
Nuclear Spill or Attack - the release of nuclear waste or materials nearby can be quickly
identified, long before official word is heard on the radio or TV.
Detection of radioactive contamination in foods - Some foods (such as certain seafoods, like
prawn) have been known to be contaminated with radioactive materials. The GM-10 can detect
radiation levels even slightly above background.
Checking for radioactive materials - Various materials, such as bricks, stones, steel, etc,
can be contaminated with radioactive materials, either due to man made waste being added, or
naturally occuring minerals. The GM-10 can detect these potentially dangerous conditions.
Likewise, packages can be scanned to determine that they are not radioactive, or contain