IVIS
®
Lumina XRMS Series III Hardware Manual
Chapter 5 | X-ray Safety and Radiation Hazards
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overlap when discussing ultra-violent radiation. X-rays are a form of electromagnetic radiation
similar to light, but having much shorter wavelengths. X-rays have wavelengths from 10 to 0.01
nanometers, whereas visible light ranges from 700 to 400 nanometers. Non-visible ultraviolet light
fills the gap between visible light and X-rays with wavelengths ranging from 400 to 10 nanometers.
It too is considered an ionizing radiation, but it does not possess the penetrating capability of X-rays.
In summary, X-ray radiation is an ionizing form of electromagnetic radiation that has sufficient
energy to break chemical bonds.
The IVIS Lumina XRMS series III uses an X-ray generating tube to produce ionizing radiation,
which if left unshielded could be harmful to people or animals. The IVIS Lumina XRMS Series III
produces ionizing radiation in the energy range from 20 to 40 kilovolts (X-ray). The IVIS Lumina
XRMS Series III has been shielded by design so that the X-rays are completely confined within the
imaging chamber. Consequently, operation of the IVIS Lumina XRMS Series III poses no unsafe
exposure to its operator. To verify the design, and to assure proper manufacturing and installation, at
least two complete radiation surveys are conducted to make certain that there is no leakage from the
instrument that exceeds US and international regulations. It is the user’s responsibility to minimize
the total X-ray exposure to the individual mouse or other animal subject as part of the total amount
of time spent imaging.
X-rays: An Ionizing Radiation
As noted above, X-rays are considered ionizing radiation capable of removing or rearranging the
electronic bonds of chemical compounds. For this reason they are considered potentially hazardous
to living organisms. X-rays can also interact with matter by scattering off of atoms in new directions.
For this reason, the IVIS Lumina XRMS Series III has shielding that completely blocks scattered
radiation in all possible directions, including the primary beam direction. Ionizing radiation can also
be produced by radioactive materials, but IVIS Lumina XRMS Series III contains no radioactive
materials. This is important because there is no possibility of transferring a radioactive contaminant
into the laboratory during a procedure such as cleaning the imaging chamber.
X-rays: A Penetrating Radiation
X-rays are able to penetrate matter. This is why they are useful in applications such as medical
imaging and industrial inspection. The IVIS Lumina XRMS Series III uses an X-ray tube source of
the minimal energy needed to penetrate and image mice. Even though X-rays are able to penetrate
matter such as tissue or plastic, they are not able to make it radioactive.
X-rays: How They are Made
The source of X-rays used in the IVIS Lumina XRMS Series III is an X-ray tube located in the area
under the imaging chamber. The characteristics of this tube are discussed in
. The basic function of the X-ray tube is to generate X-rays of a
maximum energy of 40000 electron volts. The X-rays are produced by the collision of high energy
electrons with a tungsten metal target in a vacuum tube. When a high voltage is applied between a
heated cathode and the tungsten anode, electrons are stripped from the cathode and are accelerated
into the anode. The collision of those electrons produces X-rays. There are two atomic processes
capable of producing X-rays from these collisions. One process, known as bremsstrahlung from the
German "braking radiation", generates X-rays by the rapid deceleration of the high energy electrons
as they interact with the repulsive electron field of the tungsten target metal. The second generating
process results from the high energy free electrons interacting with the target metals atomic orbitals.
The tube used in the IVIS Lumina XRMS Series III generates X-rays by means of both of these
processes. The tube generates a spectrum of X-rays from approximately 5 keV to the maximum of
40 keV. The X-ray generating source assembly is equipped with a user-activated aluminum X-ray
