Del Medical DynaRad Phantom-8000, Инструкция по установке, эксплуатации и обслуживанию

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Phantom Installation, Operation & Service Manual
i-10 Radiation Protection
Radiation Protection
Serious unfavorable health effects can result from short term exposure to
high levels of ionizing radiation (such as X-rays) as well as from long term
exposure to low levels. Personnel who operate the Phantom should
familiarize themselves with both the short term and the long term effects
of radiation exposure and take appropriate measures to minimize the
amount of radiation to which they are exposed while performing their
duties. Some effects of X-ray radiation are cumulative, and may extend
over a period of months or years. The best safety rule for X-ray operators
is to avoid exposure to the primary beam at all times.
Ionizing radiation occurs naturally in the environment. It is generated by
astronomical radiation sources such as the sun and the stars, and by the
soil under our feet. The atmosphere filters radiation from astronomical
sources. As a result, the radiation level from these sources is much lower
at sea level than on the summit of high mountains. Radiation generated in
the soil varies greatly from place to place depending on the composition of
the soil. For example, areas rich in granite rock have a higher level of
radiation than other areas.
Any materials placed in the path of the beam absorb natural as well as
man-made radiation, such as the X-rays used in the Phantom. Materials
with a high atomic number, such as tungsten, lead, and uranium, absorb
X-rays much more effectively than materials with a low atomic number
such as hydrogen, aluminum, or beryllium. Therefore, lead is used for
shielding the radiologist's workstation in most X-ray facilities, including
ones using the Phantom. If there are windows in the partition separating
the operator from the patient, these windows are typically glazed with
lead glass and provide effective protection against ionizing radiation.
To minimize dangerous exposure, use movable lead screens,
lead-impregnated gloves, and lead-impregnated aprons. These protective
devices must contain 0.25 millimeter thickness of lead or the equivalent.
Use such protective devices for all operators, observers, and/or servicing
personnel exposed to radiation fields of five or more milli-Roentgens per
hour.
The shielding provided for a typical X-ray facility's operator workstation
is generally quite effective and reduces the residual radiation from
diagnostic X-rays to a level that is comparable to or lower than natural
background radiation. If the operator abandons the protected
environment of the workstation, he or she may be exposed to a
significantly higher level of radiation. For a single exposure this may still
not lead to serious health effects, but repeated carelessness in this regard
may lead to serious consequences.
Any object in the path of the primary beam produces scattered radiation.
In the absence of proper precautions, scattered radiation can result in a