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Title: Radiation Safety for the Use of Non-Medical X-Ray Training


1
Radiation Safety for the Use of Non-Medical
X-Ray Training
2
Instructor
  • Dennis Widner
  • Health Physicist TrainingRadiation Safety
    OfficeUniversity of Georgia
  • 706-542-0526

3
INTRODUCTION
  • The purpose of this safety presentation is to
    increase your knowledge in order to enable you to
    perform your job safely by adhering to proper
    radiation protection practices while working with
    or around x-ray-generating devices. This course
    will inform you about the policies and procedures
    you should follow to reduce the risk of exposure
    to the ionizing radiation produced by
    x-ray-generating devices.

4
Georgia DHR Training Outline
  • Fundamentals of Radiation Safety
  • Characteristics of radiation
  • Units of radiation measurement
  • Significance of radiation dose and exposure
    (radiation protection standards and biological
    effects)
  • Sources and levels of radiation
  • Methods of controlling radiation dose (time,
    distance, and shielding)
  • Radiation Detection Instrumentation to be Used
  • Use of radiation survey instruments (operation,
    calibration, limitations)
  • Use of personnel monitoring equipment (dosimetry)
  • Radiographic Equipment to be Used
  • Remote handling equipment
  • Radiographic exposure devices
  • Operation and control of x-ray equipment
  • Pertinent Federal and State Regulations
  • The Registered Users Written Operating and
    Emergency Procedures
  • Case Histories of Radiography Accidents

5
INSTRUCTION OF PERSONNEL
  • The registrant (UGA) shall assure that all
    radiation machines and associated equipment under
    his control are operated only by individuals
    instructed in safe operating procedures and are
    competent in the safe use of the equipment.
  • UGA shall also assure that persons operating
    radiation machines and associated equipment
    receive 2 hours of training in radiation safety
    within 90 days after employment. Training can be
    performed by the researcher or by attending the
    UGA/RSO X-ray class.

6
TRAINING DOCUMENTATION
  • Each user of a radiation machine and associated
    equipment must have documented training records
    for operation and safety. These records shall be
    maintained in the laboratory for the lifetime of
    operation.
  • The Researcher, Principal Investigator or
    Supervisor is responsible for these records.

7
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8
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9
ORGANIZE RECORDS IN 3 RING BINDER
MAINTENANCE
INSPECTIONS
OPERATION PROCEDURE
EMERGENCY PROCEDURE
QUARTERLY CHECKS
TRAINING
REGISTRATION
EQUIPMENT
  • Equipment Specifications and output
  • Registration documents
  • Training Records
  • Quarterly Safety Checks/ Surveys
  • Operation and Emergency Procedures
  • Maintenance records
  • Inspection Results

10
Compentency
  • Identification of the radiation hazards
    associated with the operation of your equipment.
  • Understanding the significance of equipment
    warnings, safety devices and interlocks.
  • Adherence to operating procedures
  • Recognize acute exposure symptoms andhow to
    report an acute exposure
  • Any exposure should be reported to UGA Radiation
    Safety Office at 542-5801 or 542-0107

11
CATEGORIES OF X-RAY MACHINES
12
How X-Ray Machines Work
Vacuum Tube
Cathode - Electrons
Anode - Target (W) (Al)(Mo)
Wire Filament
Filter
Power
13
INTENTIONAL
An intentional x-ray device is designed to
generate an x-ray beam for a particular use.
Intentional x-rays are typically housed within a
fixed, interlocked and/or shielded enclosure or
room. Examples include x-ray diffraction and
fluorescence analysis systems, flash x-ray
systems, medical x-ray machines, and industrial
cabinet and non-cabinet x-ray installations.
INCIDENTAL
An incidental x-ray device produces x-rays that
are not wanted or used as a part of the designed
purpose of the machine. Examples of incidental
systems are computer monitors, televisions,
electron microscopes, high-voltage electron guns,
electron-beam welding machines, and electrostatic
separators.
14
Intentional Analytical X-Ray Devices
Analytical X-Ray Devices Analytical x-ray
devices use x-rays for diffraction or
fluorescence experiments as research tools,
especially in materials science. ANSI N43.2
defines two types of analytical x-ray systems
enclosed beam and open beam.
15
Safety requirements and features for analytical
systems include the following control panel
labels with the words CAUTION HIGH
INTENSITY X-RAY BEAM fail-safe lights with the
words X-RAYS ON near x-ray tube housings,
fail-safe indicators with the words SHUTTER
OPEN for beam shutters,
16
fail-safe interlocks on access doors and
panels, beam stops or other barriers, and
appropriate shielding.
17
Enclosed-Beam System In an enclosed-beam system,
all possible x-ray paths (primary and diffracted)
are completely enclosed so that no part of a
human body can be exposed to the beam during
normal operation. Because it is safer, the
enclosed-beam system should be selected over the
open-beam system whenever possible. The x-ray
tube, sample, detector, and analyzing crystal (if
used) must be enclosed in a chamber or coupled
chambers. The sample chamber must have a shutter
or a fail-safe interlock so that no part of the
body can enter the chamber during normal
operation.
18
The dose rate measured at 10 inches (25 cm) from
the apparatus must not exceed 2.0 mR per hour
during normal operation.
19
Open-Beam System In an open-beam system, one or
more x-ray beams are not enclosed, making
exposure of human body parts possible during
normal operation. The open-beam system is
acceptable for use only if an enclosed-beam
system is impractical for any of the following
reasons a need for making adjustments with
the x-ray beam energized, a need
for frequent changes of attachments and
configurations, motion of specimen and detector
over wide angular limits, or the examination of
large or bulky samples.
20
An open-beam x-ray system must have a guard or
interlock to prevent entry of any part of the
body into the primary beam. Each port of the
x-ray tube housing must have a beam shutter with
a conspicuous shutter-open indicator of fail-safe
design. The dose rate from tube leakage at 2
inches (5 cm) from the surface of the tube
housing must not exceed 25 mR per hour during
normal operation. The dose rate at 2 inches (5
cm) from the surface of the HV power supply must
not exceed 0.5 mR per hour during normal
operation.
21
NON-MEDICAL FLUOROSCOPY
Hand held fluoroscopes shall not be used The
dose rate due to transmission through the image
receptor shall not exceed 2 mR/hr at 4 inches (
10 cm) from any point On the receptor. The
maximum x-ray dose shall not exceed 0.5 mR in
any one hour measures at 2 inches ( 5 cm) from
any readily accessible machine surface
22
Intentional Industrial X-Ray Devices
Industrial x-ray devices are used for
radiography for example, to take pictures of the
inside of an object as in a medical chest x-ray
or to measure the thickness of material. ANSI
N43.3 defines three classes of industrial x-ray
installations
  • Cabinet
  • exempt shielded
  • shielded.

23
Incidental X-Ray Devices
In a research environment, many devices produce
incidental x-rays. Any device that combines high
voltage, a vacuum, and a source of electrons
could, in principle, produce x-rays. For
example, a television or computer monitor
generates incidental x-rays, but in modern
designs the intensity is low, much less than 0.5
mR per hour. Occasionally, the hazard associated
with the production of incidental x-rays is
recognized only after the device has operated for
some time. If you suspect an x-ray hazard,
contact UGA Radiation Safety to survey the
device.
24
Electron Microscopes
The exposure rate during any phase of operation
of an electron microscope at the maximum rated
continuous beam current for the maximum rated
accelerating potential should not exceed 0.5 mR
per hour at 2 inches (5 cm) from any accessible
external surface.
25
Mandatory Quarterly Safety Checks
26
X-Ray Safety Training
  • Fundamentals of Radiation Safety

27
What is Radioactivity?
Characteristics of Radiation
  • What are X-rays ?

What is scatter ?
28
Radioactivity
Definition Any spontaneous change in the state of
a nucleus accompanied by the release of energy.
Major Types
alpha (?) particle emission beta (?) particle
emission gamma (?) decayX-ray (X)
Characteristic and Bremsstrahlung
29
X-Rays
X-rays are photons (electromagnetic radiation)
which originate in the energy shells of an atom,
as opposed to gamma rays, which are produced in
the nucleus of an atom.
30
Soft vs. Hard X-rays
X-rays from about 0.12 to 12 keV (10 to 0.10 nm
wavelength) are classified as "soft" X-rays, and
from about 12 to 120 keV (0.10 to 0.01 nm
wavelength) as "hard" X-rays, due to their
penetrating abilities.3
31
X-ray Tube Target Material
In medical X-ray tubes the target is usually
Tungsten (W) or a more crack-resistant alloy of
Rhenium (Re) (5) and tungsten (95), but
sometimes Molybdenum (Mo) for more specialized
applications, such as when soft X-rays are needed
as in mammography. In crystallography, a Copper
(Cu) target is most common, with Cobalt (Co)
often being used when fluorescence from Iron
(Fe)content in the sample might otherwise present
a problem.
32
X-Ray Scatter
When x-rays pass through any material, some will
be transmitted, some will be absorbed, and some
will scatter. The proportions depend on the
photon energy and the type of material. X-rays
can scatter off a target to the surrounding area,
off a wall and into an adjacent room, and over
and around shielding. A common mistake is to
install thick shielding walls around an x-ray
source but ignore the need for a roof, based on
the assumption that x-rays travel in a straight
line. The x-rays that scatter over and around
shielding walls are known as skyshine.
33
On November 8, 1895, at the University of
Wurzburg, Wilhelm Roentgen's attention was drawn
to a glowing fluorescent screen on a nearby
table. Roentgen immediately determined that the
fluorescence was caused by invisible rays
originating from the partially evacuated glass
Hittorf-Crookes tube he was using to study
cathode rays (i.e., electrons). Surprisingly,
these mysterious rays penetrated the opaque black
paper wrapped around the tube. Roentgen
haddiscovered X rays, a momentous event that
instantly revolutionized the field of physics and
medicine.
Wilhelm Conrad Roentgen (1845-1923)
34
X-rays
  • X-rays are Electromagnetic Radiation (EMR)

35
EM radiation can be viewed as a waves or bundles
ofenergy called photons. Electromagnetic
radiation (EM) is the transport of energy through
space as a combination of electric and magnetic
fields The EM wave can be visualized as an
oscillating electric field with a similar varying
magnetic field changing with time and at right
angles to it.
36
X-ray wavelengths are typically measured in units
of angstroms Å 1 E-10 meters(0.0000000001
m)1 nanometer 1 E-9 meter 1 nm 10 Å The
x-ray region is normally considered to be that
region of the EM spectrum lying between 0.1 and
100 Åin wavelengthorX-ray energies between 0.1
and 100 keV
37
How small is an angstrom?  
  • The point of a needle is about 1 million
    angstroms in diameter.
  • Fingernails grow at about 50 angstroms per
    second.
  • One angstrom is to a grain of sand, as a child's
    wading pool is to the Atlantic Ocean.

38
Types of X-rays
Characteristic vs Bremsstrahlung
X-rays can be produced by either by the
interaction of the bombarding electrons that are
braked by the Coulomb force field of the target
nuclei (Bremsstrahlung x-ray production)
Collision interactions with atomic electrons of
the target material (characteristic x-ray
emission).
39
Ionizing Radiation
Definition - Any type of radiation possessing
enough energy to eject an electron from an atom,
thus producing an ion.
X-Rays and Gamma photons are both
electromagnetic radiations that have the energy
to ionize atoms
X-Ray
40
  • Fundamentals of Radiation Safety

Units of Radiation Measurement
41
DOSE UNITS OF MEASURE
  • Ionizing radiation is measured in the following
    units
  • roentgen (R), the measure of exposure to
    radiation, defined by the ionization caused by
    x-rays in air.
  • rad, the radiation absorbed dose or energy
    absorbed per unit mass of a specified absorber.
  • rem, the roentgen equivalent man or dose
    equivalent.

42
Georgia Radiation Dose Units
MilliRoentgen (mR)or Roentgen (R)
Georgia Radiation Dose rate Units
MilliRoentgens per hour (mR/hr)or Roentgens per
hour (R/hr)
43
  • Fundamentals of Radiation Safety

Significance of Radiation Dose and Exposure
44
Health Effects of Radiation
Ionizing Radiation can directly and indirectly
damage DNA
DNA Double Helix
Radiation
  • Acute Exposure Effects (Stochastic)
  • Radiation in large doses in a short time causes
    observable damage .observable at gt25 Rem
  • Chronic Exposure Effects (Non-stochastic)
  • The effects from radiation exposure decrease as
    the dose rate is lowered. Spreading the dose
    over a longer period reduces the effects. Much
    of the controversy over radiation exposure
    centers on the question of how much damage is
    done by radiation delivered at low doses or low
    dose rates.

45
Dose Response Model
Known Effects
Atomic Bomb Survivors
Uranium Miners
Radium Dial Painters
Medical Patients
Health Effect (cancer)
  1. Linear No Threshold Dose Curve
  2. Decreased Health Effects Theory
  3. Threshold Dose Theory
  4. Increased Health Effects Theory

4
Theo. Debated Effects
1
2
The NRC and The State of Georgia Follow the
Linear No Threshold Theory
3
Dose (rem)
46
How does radiation cause health effects?
Radioactive materials that decay spontaneously
produce ionizing radiation, which has sufficient
energy to strip away electrons from atoms
(creating two charged ions) or to break some
chemical bonds. Any living tissue in the human
body can be damaged by ionizing radiation. The
body attempts to repair the damage, but sometimes
the damage is too severe or widespread, or
mistakes are made in the natural repair process.
The most common forms of ionizing radiation are
alpha and beta particles, or gamma and X-rays. 
47
What kinds of health effects occur from exposure
to X-rays?
  • In general, the amount and duration of x-ray
    exposure affects the severity or type of health
    effect. There are two broad categories of health
    effects stochastic and non-stochastic.

48
Stochastic Health Effects
Stochastic effects are associated with long-term,
low-level (chronic) exposure to radiation.
("Stochastic" refers to the likelihood that
something will happen.) Increased levels of
exposure make these health effects more likely to
occur, but do not influence the type or severity
of the effect.
Cancer is considered by most people the primary
health effect from radiation exposure. Simply
put, cancer is the uncontrolled growth of cells.
Ordinarily, natural processes control the rate at
which cells grow and  replace themselves. They
also control the body's processes for repairing
or replacing damaged tissue. Damage occurring at
the cellular or molecular level, can disrupt the
control processes, permitting the uncontrolled
growth of cells--cancer. This is why ionizing
radiation's ability to break chemical bonds in
atoms and molecules makes it such a potent
carcinogen.
Other stochastic effects also occur. Radiation
can cause changes in DNA, the "blueprints" that
ensure cell repair and replacement produces a
perfect copy of the original cell. Changes in DNA
are called mutations.
Sometimes the body fails to repair these
mutations or even creates mutations during
repair. The mutations can be teratogenic or
genetic. Teratogenic mutations affect only the
individual who was exposed. Genetic mutations 
are passed on to offspring.
49
Non-Stochastic Health Effects
Non-stochastic effects appear in cases of
exposure to high levels of radiation, and become
more severe as the exposure increases. Short-term,
high-level exposure is referred to as 'acute'
exposure. 
Many non-cancerous health effects of radiation
are non-stochastic. Unlike cancer, health effects
from 'acute' exposure to radiation usually appear
quickly. Acute health effects include burns and
radiation sickness. Radiation sickness is also
called 'radiation poisoning.'  It can cause
premature aging or even death. If the dose is
fatal, death usually occurs within two months.
The symptoms of radiation sickness include
nausea, weakness, hair loss, skin burns or
diminished organ function. 
Medical patients receiving radiation treatments
often experience acute effects, because they are
receiving relatively high "bursts" of radiation
during treatment. 
50
What is the cancer risk from radiation? How does
it compare to the risk of cancer from other
sources?
Each radionuclide represents a somewhat different
health risk.  However, health physicists
currently estimate that overall, if each person
in a group of 10,000 people exposed to 1 rem of
ionizing radiation, in small doses over a life
time, we would expect 5 or 6 more people to die
of cancer than would otherwise. ( 0.06)
In this group of 10,000 people, we can expect
about 2,000 to die of cancer from all
non-radiation causes. The accumulated exposure to
1 rem of radiation, would increase that number to
about 2005 or 2006.  
  • To give you an idea of the usual rate of
    exposure, most people receive about 3 tenths of a
    rem (300 mrem) every year from natural background
    sources of radiation (mostly radon).

51
What are the risks of other long-term health
effects?
Other than cancer, the most prominent long-term
health effects are teratogenic and genetic
mutations. 
Teratogenic mutations result from the exposure of
fetuses (unborn children) to radiation. They can
include smaller head or brain size, poorly formed
eyes, abnormally slow growth, and mental
retardation. Studies indicate that fetuses are
most sensitive between about eight to fifteen 
weeks after conception. They remain somewhat less
sensitive between six and twenty-five weeks old. 
The relationship between dose and mental
retardation is not known exactly. However,
scientists estimate that if 1,000 fetuses that
were between eight and fifteen weeks old were
exposed to one rem, four fetuses would become
mentally retarded. If the fetuses were between
sixteen and twenty-five weeks old, it is
estimated that one of them would be mentally
retarded.
52
Genetic effects are those that can be passed from
parent to child. Health physicists estimate that
about fifty severe hereditary effects will occur
in a group of one million live-born children
whose parents were both exposed to one rem. About
one hundred twenty severe hereditary effects
would occur in all descendants.  
In comparison, all other causes of genetic
effects result in as many as 100,000 severe
hereditary effects in one million live-born
children. These genetic effects include those
that occur spontaneously ("just happen") as well
as those that have non-radioactive causes.
53
X-Ray Burns versus Thermal Burns
Most nerve endings are near the surface of the
skin, so they give immediate warning of a surface
burn such as you might receive from touching a
high temperature object. In contrast, high-energy
x-rays readily penetrate the outer layer of skin
that contains most of the nerve endings, so you
may not feel an x-ray burn until the damage has
been done. X-ray burns do not harm the outer,
mature, non-dividing skin layers. Rather,
thex-rays penetrate to the deeper, basal skin
layer, damaging or killing the rapidly dividing
germinal cells that were destined to replace the
outer layers that slough off. Following this
damage, the outer cells that are naturally
sloughed off are not replaced. Lack of a fully
viable basal layer of cells means that x-ray
burns are slow to heal, and in some cases, may
never heal. Frequently, such burns require skin
grafts. In some cases, severe x-ray burns have
resulted in gangrene and amputation of a finger.
The important variable is the energy of the
radiation. Heat radiation is infrared, typically
1 eV sunburn is caused by ultraviolet radiation,
typically 4 eV x-rays are typically 10 to 100
KeV.
54
Signs and Symptoms of Exposure to X-Rays
500 rem. An acute dose of about 500 rem to a part
of the body causes a radiation burn equivalent to
a first-degree thermal burn or mild sunburn.
Typically, there is no immediate pain, but a
sensation of warmth or itching occurs within
about a day after exposure. A reddening or
inflammation of the affected area usually appears
within a day and fades after a few more days. The
reddening may reappear as late as two to three
weeks after the exposure. A dry scaling or
peeling of the irradiated portion of the skin is
likely to follow.
55
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56
An acute dose of about 600-900 rem to the lens of
the eye causes a cataract to begin to form.
gt1,000 rem. An acute dose of greater than 1,000
rem to a part of the body causes serious tissue
damage similar to a second-degree thermal burn.
First reddening and inflammation occurs, followed
by swelling and tenderness. Blisters will form
within one to three weeks and will break open
leaving raw, painful wounds that can become
infected. Hands exposed to such a dose become
stiff and finger motion is often painful. If you
develop symptoms such as these, seek immediate
medical attention to avoid infection and relieve
pain.
57
Photon burns to the fingers
58
An even larger acute dose causes severe tissue
damage similar to a scalding or chemical burn.
Intense pain and swelling occurs, sometimes
within hours. For this type of radiation burn,
seek immediate medical treatment to reduce pain.
The injury may not heal without surgical removal
of exposed tissue and skin grafting to cover the
wound. Damage to blood vessels also occurs, which
can lead to gangrene and amputation. A typical
x-ray device can produce such a dose in about 3
seconds. For example, the dose rate from an x-ray
device with a tungsten anode and a beryllium
window operating at 50 KeV and 20 mA produces
about 900 rem per second at 7.5 cm.
59
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60
  • Fundamentals of Radiation Safety

Methods of Controlling Radiation Dose
61
Fallout, Products, Air Travel, Nuclear
operations 12.2 mrem/yr
Cosmic External Terrestrial 72 mrem/yr
Nuclear Medicine 14 mrem/yr
Diagnostic X-ray 39 mrem/yr
Internal Terrestrial 40 mrem/yr
Radon in home 200 mrem/yr
Average Background Dose in U.S. is 360 mrem. In
Georgia it is 377.2 mrem
62
What are the hazards associated with X-ray
producing equipment?
  • Direct exposure to the primary x-ray beam

2. X-ray Scatter
63
A L A R A
Philosophy
Radiation doses are kept as low as possible Stems
from Linear-No-Threshold dose model ALARA program
required by Federal and State regulations
LNT Model
64
Reducing External Radiation Exposure
  • Time
  • reduce time spent in radiation area
  • Distance
  • stay as far away from the radiation source as
    possible
  • Shielding
  • interpose appropriate materials between the
    source and the body

65
X-Ray Safety Training
  • Radiation Detection Instrumentation

66
Ion Chamber Survey Meter
67
Geiger-Mueller Survey Meter
Ludlum model 3 instrument (Part No. 48-1605) with
a 202-608 meter dial and extra cable
68
Recommended Survey Probes
69
  • Monitoring of External
  • Radiation Dose
  • TLDs are only given out for open beam operators
  • Primary dosimeter is the Luxel crystal
  • Sensitive to gamma, x-ray and hard beta
    radiations
  • Provides dose information on a monthly basis
  • Does not provide information during an exposure
    to radiation
  • Supplementary dosimeters - pocket dosimeters /
    radiation survey instruments, room monitors

70
Body Badge Location
Badge
Source
Between Neck and Waist Closest to Source of
Radiation
Ring Badge
71
  • Monitoring of External
  • Radiation Dose
  • Individual responsibility to change badge
  • Badge Exchange
  • Not Contaminated
  • Badge Book Location
  • Change Out Procedure

72
X-Ray Safety Training
  • Pertinent Federal and State Regulations

73
Georgia Department of Human Resources
  • Key Parts of the Rules and Regulations for
    X-rays, Chapter 290-5-22
  • Part .01 General Provisions
  • Part .02 Registration
  • Part .03 Standards for the Protection Against
    Radiation
  • Part .06 Radiation Safety Requirements
  • for the Use of Non-Medical X-ray
  • Part .07 Records, Reports and Notification

74
290-5-22-.01
General Provisions
  1. Regulations apply to all uses of radiation
    machinesin the healing arts, industry,
    educational and research institutions.
  2. Radiation shall not be applied to individuals
    except as prescribed by persons licensed to
    practice in the healing arts or authorized to do
    so.
  3. The operation of any radiation machine in Georgia
    is prohibited unless the user is registered with
    the Department.
  4. The Department is authorized to inspect,
    determine compliance and conduct tests of your
    equipment.

75
290-5-22-.01
General Provisions
  1. Each facility shall be provided with such primary
    and secondary barriers to assure compliance.
  2. Shielding design review and approval before any
    new construction of any x-ray facility.
  3. Copy of design kept on file at the facility.
  4. Out of compliance corrections and notifications
    are due to the Department within 60 days.
  5. The Department has the authority to impound

76
290-5-22-.02
Registration
290-5-22-.03
Standards for the Protection Against Radiation
  1. Exposure in milliroentgens
  2. Permissible doses
  3. Personnel monitoring
  4. Caution signs, Labels and Signals

77
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78
290-5-22-.06
Radiation Safety Requirements for the Use of
Non-Medical X-ray
290-5-22-.07, .08, and .09
Records, Reports and Notifications/Penalties/Enfor
cement
79
Federal Regulations
  • Code of Federal Regulations
  • 21 CFR 1020.4
  • 10 CFR 20

The American National Standards Institute (ANSI)
details safety guidelines for x-ray devices in
two standards, one on analytical (x-ray
diffraction and fluorescence) x-ray equipment and
the other on industrial (non-medical) x-ray
installations.
80
Occupational Dose Limits for X-Ray Workers
Whole bodyhead and trunkblood forming
organslens of eyes gonads
Source of Radiation
Dose is not to exceed 1.25 Rem/Quarter
81
Occupational Exposure Limit to the Extremities
The Dose Limit to the Extremities may not exceed
18.75 rem / qtr
82
Occupational Dose to the Skin of Whole Body
Dose must not exceed 7.5 rem/ qtr
83
Occupational Dose Limit for Declared Pregnant
Mothers and Occupational Minors
50 mrem/month limit
Dose must not exceed 0.5 rem or 500 mrem during
the gestation period for declared pregnant
mothers. Occupational minors must not exceed
this dose in a year long period
84
Annual Dose Limit to a General Member of the
Population
X-ray room
Must not exceed 10 of the occupational limits
85
X-Ray Safety Training
  • The Registered Users Written Operating and
    Emergency Procedures

86
Write your own operating and emergency
procedures, no matter how detailed or how large
or small of a document. Use the vendors
manual in assisting your generation of your
manualUse the radiation safety training to
supplement as well.Everyone must be trained on
your operation and safety procedures and
document training.Both operating and emergency
procedures must be present at all times.
87
X-Ray Safety Training
  • Case Histories of Radiography Accidents

88
Dr. Mihran Kassabian
89
Mihran Kassabian documented and photographed his
degeneration, hoping to help later technicians
and patients avoid his fate.
90
On April 4, 1974, a worker (worker A) who had
been repairing an x-ray spectrometer noticed
redness, thickening, and blisters on both hands.
At the medical center, the doctors tried
nonspecific anti-inflammatory measures, without
effect. Later that month, two coworkers (workers
B and C) noticed similar skin changes, and the
true nature of the problem became evident. On
March 21, March 29, April 2, and April 4, the
three workers had been working to repair a 40-kV,
30-mA x-ray spectrometer. In the absence of the
usual repair people, the three workers were not
aware that the warning light was not
operating and that the device was generating
x-rays estimated at 100 R/min. During the
work, all three had received doses of gt1,000 R to
their hands. By May 9, the acute reactions had
largely subsided, but worker A developed
a shallow necrotic ulcer on the right index
finger and another on the left ring finger. Over
the next few weeks, the ulcer on the left ring
finger gradually healed, but the right index
finger became increasingly painful. In June,
three months after the x-ray exposure, the ulcer
began to spread, extending up the finger toward
the knuckle. On July 19, the finger was
amputated. In August, a painful ulcer developed
on the left middle finger. Surgery was performed
to sever some nerves, and the finger
healed satisfactorily after a few weeks. Worker B
received a much smaller dose than worker A.
Blisters formed during April and completely
healed during May. When last seen, four years
after the x-ray exposure, some abnormalities were
still apparent but without any long-term disabilit
y.
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Worker C was exposed only on April 4. On April
17, he felt a burning pain and noticed redness on
the fingers of both hands. By May 20, these
injuries appeared to heal, leaving no apparent
disability. However, in November, a minor injury
to his left hand developed into an ulcer that
appeared to be like the ulcers on patient
A. Worker Cs ulcer healed in December without
requiring surgery. In a separate accident on July
26, 1994, a 23-year-old engineer was repairing a
40- kV, 70-mA x-ray spectrometer. He removed
several panels and inserted his hand for 56
seconds at a distance 6-8 cm from the x-ray tube,
before realizing that he had failed to
de-energize the device. The engineer recalled
having a sensation of tingling and itching in his
fingers the day after the accident. A pinching
sensation, swelling, and redness were
present between days four and seven. By day
seven, a large blister was developing,
in addition to increased swelling and redness.
One month after the accident, the entire hand was
discolored, painful, and extremely sensitive to
the slightest touch. Blood circulation to the
entire hand was low, especially to the index and
middle fingers. Surgery was performed to sever
the sympathetic nerve to allow the constricted
blood vessels to dilate, and a skin graft was
sutured in place. One month later, the hand had
returned to a normal color and the skin graft was
adherent.
92
In the early 1970s in Pennsylvania, 1.8 of all
X-ray users worked with analytical X-ray
(definition) instruments (rather than medical,
dental, or industrial X-ray). This relatively
small number of users was involved in 76 of the
serious radiation accidents. Why are analytical
X-ray users such a high-risk group?     There
are a number of factors involved in risk, but the
most significant can probably be categorized into
equipment and training.     By its nature, the
equipment produces an intense, highly collimated
beam of high-energy radiation that cannot be
sensed physically at the time of exposure.
Consequently, a number of protective devices and
features are required on instruments currently
being marketed to reduce the hazards, greatly
reducing the accident rate among users.     The
other factor, training, includes knowing proper
procedures for using the machine, hazard
awareness, and in some cases, safety attitude
adjustments.
93
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94
X-Ray overdose from misuse during angioplasty
95
Questions ???
If you have any questions while reading the
Radiation Safety Manual
Please Feel Free to Contact The Radiation
Safety Office
Environmental Safety Division University of
Georgia 240A Riverbend Road Athens, Georgia
30602-8002
Radiation Safety Office
542-5801
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