Dental X-Ray Safety Training Radiation Safety Program Safety,
Health, Environment & Risk Management (SHERM) 713-500-5840
Slide 2 THE SHERM MISSION Safety, Health, Environment and Risk
Managements (SHERM) mission is to work in conjunction with the
UTHSC-H community to ensure that education, research, and health
care services activities take place in conditions that are
optimally safe and healthy for all student, faculty, staff,
visitors, surrounding community and the general public. Put simply,
we exist to help people go home as healthy and safe as they
arrived. Slide 3 Outline Fundamentals of radiation How x-rays are
produced Annual background exposure How to minimize your radiation
exposure Instructions for the radiation monitoring program
Potential biological effects from radiation exposure Operating and
Safety Procedures Access to applicable dental radiation regulations
Radiation Safety contact information Slide 4 What is radiation?
Emission of energy in the form of particles (e.g. beta) or waves
(e.g. x-rays) Ionizing radiation has enough energy to remove an
orbital electron and produce ions. Slide 5 Radiation Spectrum
RadioMicrowaveInfraredVisibleUltravioletX-ray Gamma Ray 10 3 10 -2
10 -5.5 x 10 -6 10 -8 10 -10 10 -12 Wavelength (meters)
Electromagnetic radiation travels through space in the form of
waves. Waves of all types have an associated wavelength and
frequency. Radio waves have the longest while gamma rays have the
shortest wavelength. Slide 6 Wilhelm Roentgen Discovers X-rays
November 8, 1895 While studying cathode ray tubes, he noticed that
the fluorescence occurred in a cathode ray tube even when shielded
from outside light Discovery instantly revolutionized physics and
medicine Slide 7 X-Ray Tube Tungsten Target Slide 8 X-ray Tube
Anatomy X-rays are produced by energy conversion when a fast moving
stream of electrons is suddenly slowed down in the target (e.g.
tungsten) anode of the x-ray tube. Slide 9 Natural and Manmade
Background Radiation National Annual Average Exposure is 625 mrem
Note: Medical procedures are not occupational but exposures as a
patient. Slide 10 Radon Largest contributor to background radiation
in the U.S. Noble gas not readily incorporated into tissues
deposited to the lungs via nuclides attaching to aerosols in the
air Seeps into basements and foundations of homes and buildings
location, building materials, and soil determine radon exposure
Slide 11 X-ray Output The dose to the patient may change by varying
the parameters of the x-ray machine such as: Total exposure time
Tube current (mAs) {Controls the # of x-rays} Kilovolt peak (kVp)
Beam shaping Collimation Slide 12 Minimize Exposures by Combining
the use of Least Time Greatest distance Appropriate shielding In
order to maintain doses ALARA = As Low As Reasonably Achievable
Slide 13 ALARA Techniques Minimize the time spent in unshielded
environments while the x-ray beam is on Avoid anyone beyond the
patient being in the area while x-ray beam is on Stand at least 6
feet away from the dental x-ray machine Standing 6ft away verses 1
ft away reduces the exposure by 1/36 Slide 14 X-rays are easily
shielded by a layer of dense material, like lead. Exam room walls
may be shielded to protect the public areas. Protective aprons,
leaded walls and leaded glass barriers in diagnostic radiology
often block most (~90% - 99%) of the radiation. TissuePlexiglasThin
Lead Thick Lead ALARA Techniques Slide 15 Protective Equipment
Personnel Protective Apparel Lead aprons, gloves, thyroid shields
Visual and tactile examination of leaded aprons is required
annually Slide 16 Occupational Exposure receives radiation exposure
Any worker who receives radiation exposure while performing a job
or task. The worker is required to wear dosimetry if their job
tasks produce high enough exposures that they are likely to exceed
10% of the occupational dose limits. Slide 17 Annual Radiation
Exposure Limits Occupationally Exposed Worker: remmrem Whole body
55000 Eye1515,000 Shallow5050,000 Minor0.5500 Pregnant Worker
0.5*500* *in 9 months General Public: 100 mrem/year or 2 mrem/hour
Slide 18 Dental X-ray Regulations for Monitoring Occupational
Exposures 25 TAC 289.232(d)(6) No individual monitoring shall be
required for personnel operating only dental radiation machines for
dental diagnostic purposes UTHSC-H, EH&S will monitor dental
x-ray operators who request dosimetry. Quarterly change out is
typical at UTHSC-H for personnel operating dental x-ray machines
Slide 19 How to Obtain a Badge Fill out form (RS-03) available
online or by contacting Radiation Safety Program
http://www.uth.tmc.edu/safety/radsafety/rs03.htm Slide 20
http://www.uth.tmc.edu/safety/radsafety Slide 21 Proper Badge
Locations under Wear any specially assigned abdomen badge at the
waist under any protective apron At the collar & outside any
lead apron Slide 22 Declared Pregnancy When you contact RSP
regarding your pregnancy, RSP will schedule a confidential meeting
to: Review the risks associated with prenatal exposures and methods
to minimize risks Review previous personnel monitoring results
Review exposure limits Discuss the NRC Regulatory Guide 8.13
Provide an opportunity for questions Provide additional monitoring
if appropriate Assist you in completing the written declaration
Slide 23 Declared Pregnancy Program to assess, monitor, define and
minimize exposures to the developing fetus. It is the individuals
decision to contact the Radiation Safety Program (RSP) and provide
a written declaration of pregnancy for the lower limit to be
applied. Limit is 500 mrem per gestation period With a
recommendation of a 50 mrem limit per month In rare cases, job
duties or assignments may be re- evaluated and changed.
http://www.nrc.gov/reading-rm/doc-collections/reg-guides/
occupational-health/active/8-13/index.html Slide 24 Contact the RSP
at 713-500-5840 or CYF G.102 to discuss pregnancy and radiation. We
will assist you in completing the shown (RS-14) form. Contact the
RSP at 713-500-5840 or CYF G.102 to discuss pregnancy and
radiation. We will assist you in completing the shown (RS-14) form.
http://www.uth.tmc.edu/safety/radsafety/
Pregnant%20Employee's%20Guide%20to%20Radiation.html Slide 25
Potential Biological Effects? Slide 26 Biological Damage Radiation
may Deposit Energy in Body Cause DNA Damage Create Ionizations in
Body Leading to Free Radicals Which may Lead to Biological Damage
Radiation is a weak carcinogen (chronic effect) A dose of 1,000
mrem increases your risk in cancer by 0.04% Acute effects (e.g.
erythema) have a threshold and the dose increases the severity of
effect Slide 27 Biological Effects Slide 28 Paperwork,
paperwork........ For the protection of patients & workers,
there are requirements Federal regulations State regulations UTHSCH
Standard Operating Procedures Equipment registration Equipment
Calibrations Hmmm... Slide 29 DSHS Requirements Registration for
all machines If not digital x-ray unit Log of developing chemical
replacement Darkroom tests (stray light) Annual lead apron tests
for integrity Receipt/disposal records of equipment Record of
maintenance Calibration of machines by Licensed Medical Physicist
Review of Standard Operating Procedures Documented training Patient
log Slide 30 Radiation Control, Texas Department of State Health
Services Regulations are available at:
http://www.dshs.state.tx.us/radiation/rules.shtm 25 Texas
Administrative Code (TAC) 289.231 X-ray Safety (General) 289.203
Notices to Workers 289.232 Dental Radiography Slide 31 Dental
Regulations Slide 32 General Machine Requirements Images must have
dentist orders Minimum distance is 6 feet from patient unless
standing behind protective barrier Technique chart Exclude
unnecessary personnel from area Keep out of direct beam path Use
shielding prudently (0.25 mm of lead) Minimize retakes Operators
must be credentialed Slide 33 If you are pregnant or suspect you
are, please inform the technologist BEFORE x-rays are taken. Thank
you. Postings for Radiography Rooms Slide 34 Slide 35 Overexposure
Data Background Texas Department of State Health Services Radiation
Control (DSHS-RC) (formerly known as Texas Depart of Healths Bureau
of Radiation Control (TDH-BRC)) is the designated state agency for
issues involving radiation in Texas An essential function of the
DSHS-RC is responding to incidents and complaints Records of such
events have been recorded in text format since 1956 This data is
much more thorough than any other state or federal government
agency, but is not in a format that is analyzable Previous work
performed by Dr. Robert Emery and Dr. Mike Charlton examined,
classified, and defined various events that occurred from 1988-1997
Slide 36 Quarterly Limit Annual Whole Body Limit General Public
Limit >1.25 rem per 3 month period >5 rem per year >100
mrem per year Definition of Overexposure in Texas Slide 37
(n=6,102) Reported Radiation Incidents in Texas, 1956-2000
(n=6,102) Slide 38 Overexposure Incidents in Texas by Total Dose,
1956-2000 Only 2% of the overexposures in Texas from 1956 to 2000
have been high enough to see acute clinical effects Slide 39 Near
equal prevalence of overexposures in medical and industrial
settings Significant decreases in overexposure incidents Early 80s,
likely related to oil and gas exploration activity in Texas After
1994, likely due to change in regulations Within the largest
category of events in Texas from 1956-2000, the occurrence of non-
stochastic events was rare. Initial Overexposure Conclusions Slide
40 Operating & Safety Procedures for Use of Radiation in Dental
Branch Clinics For current version contact Ms. Adkissons office
Radiation Safety Website
http://www.uth.tmc.edu/safety/radiation_safety.html Forms is the
repository for standard forms (e.g., dosimetry, training &
experience) Policies lists the basic radiation safety policies
Manuals UTHSC-H Radiation Safety Manual Radiation Safety Office
Phone Number: 713 500 5840 In an Emergency (call): (713) 500 4357
(HELP) For Assistance or More Information Slide 41
