Transcript Slide 1

Personal Radiation and
Occupational Safety – CT
Policy
• This policy is in both paper form in the
lab’s compliance manual, and on a Power
Point presentation in order that one could
provide the annual in-service or an inservice to new employees of the practice.
• The policy will be reviewed by on an
annual basis.
• Policy created: December 15, 2008
Responsibilities
• The Radiologist: To ensure that
procedures are conducted in such a
manner as to minimize exposure to
patients, public, and employees.
Responsibilities
• The Radiographer:
• The radiographer must acquire the daily
quality control testing to ensure that the
CT system is operating is a safe manner.
• The radiographer must conduct his/her
radiation safety behavior according to the
principles of ALARA (As Low as
Reasonably Achievable)
Responsibilities
• Field Service Engineer
• The field service engineer must conduct
the manufacturers required PMs
(Preventive Maintenance) and ensure that
all system components are operational.
Responsibilities
• Physicist.
• The physicist must acquire testing as
required by law to ensure that radiation
doses to both patients, and personnel, are
ALARA.
Helpful Information for
Cardiology
• Health Physics Society Ask The Experts
http://hps.org/publicinformation/asktheexperts.
cfm
• Physicist Contact Number:
Radiation Dose Limits
Type
Annual Limit
Whole Body
5,000 millirem
Extremities
50,000 mrem
Lens of the Eye
15,000 mrem
Embryo/Fetus
500 mrem
ALARA Dose Levels
• To help maintain radiation doses ALARA,
there are two dose Action Levels.
• ALARA Level 1: 125 mrem/calendar
quarter.
• ALARA Level 2: 375 mrem/calendar
quarter.
ALARA Level 1
• Level 1 is set at 10% of the annual limit, or
125 mrem per quarter. Technically, only
those who receive a dose above Level 1
are required to wear a film badge.
• A report is made to the Radiation Safety
Physicist of all doses exceeding the Level
1 threshold.
ALARA Level 2
• Level 2 is set at 30% of the annual dose
limit, or 375 mrem per quarter.
• Your physicist investigates all exposures
exceeding Levels 1 and 2, makes any
appropriate dose level reduction
recommendations, and reports to you and
the Medical Director of the Practice.
ALWAYS WEAR YOUR DOSIMETER WHILE WORKING
• Failure to wear your dosimeter while
working in the CT area makes it extremely
difficult for the health physicist to obtain an
accurate assessment of your exposure.
• Also, do not wear the same dosimeter if
you are working another job where you
may be exposed to ionizing radiation.
Badge Holder
• The plastic holder
contains a system of
filters to enable the
dosimeter reader to
determine the type of
radiation the badge
was exposed to, and
under what
circumstances.
Wearing the Dosimeter Correctly
• The dosimeter
must be worn at
the collar level
OUTSIDE the
protective apron.
Double Badges
• Staff performing interventional CT or
pregnant staff will be assigned a second
dosimeter.
• The second badge is to be worn at the
waist, UNDER the protective apron.
• The badge holders will be coded, do not
switch badges.
Care of Your Badge
• Film is damaged by
heat, water, light
and radiation.
• When not in use,
store your badge in
a cool, dry place,
away from any
sources of radiation.
• Do not bring your
badge home!
A good place to store your
badge when not wearing it –
a badge rack outside the xray suite.
Lost or Damaged Badges
• Report any of the following IMMEDIATELY
to Radiation Safety (Physicist):
– Lost dosimeters.
– Damaged dosimeters.
– Dosimeters that have received a high dose of
radiation.
What Dose Did You Receive?
• Under normal circumstances, Your
physicist should report to you if your
quarterly dose exceeds Level 1. If you do
not receive a report, your dose is below
ALARA.
• You may contact your physicist at any time
if you wish to learn the results of film
badge monitoring.
Guess how this happened?
Pregnant Workers
Pregnant Workers
Pregnant Workers should be limited to
500 mRem/9 months.
Extra radiation badges to wear at the waist
are available to pregnant radiation workers.
Time, Distance Shielding
• Time: If involved in an interventional
procedure, make sure the radiologist
knows the total exposure time.
• The less time exposed to radiation, the
smaller the dose, all other factors being
the same.
Distance
• Distance - stand as far away from the
patient during fluoro as feasible . When
not actually assisting, stand in the control
booth.
Shielding
• Shielding – stand completely behind the control booth
lead wall during x-ray exposures
• All workers in the x-ray room during
studies must have a lead apron.
• Keep the lead between you and
the x-ray tube. That is, do not
turn your unshielded back to
the x-ray machine.
Thyroid Shielding
• Use of a thyroid shield keeps worker’s
•
radiation dose ALARA [as low as
• reasonably achievable.]
• Those persons who are within three feet of
the patient during a fluoroscopy study
should be wearing a thyroid shield.
• Ensure there is no gap between the
thyroid shield and the lead apron.
Lead Aprons
•
•
•
•
•
Hang aprons and shields on racks.
Do not bend or fold lead aprons or shields.
Folding can cause cracks and tears in
the protective material.
Inspect shields for evidence of damage.
CT Shielding
1.3 μGy/sec = 0.13
mrem/sec;
~4 mrem for a 30
second scan at the
outer isodose
boundary.
Don’t stand in an
open doorway
during scanning!
Signs
• For employee and public protection, locate
a red warning light with the notation "XRAY ON" or the equivalent, on the control
panel and outside door which will be lit
only when the X-ray tube is activated.
Signs, Continued
•Place a label bearing the radiation symbol and the words "CAUTION –
Radiation Area” on or adjacent to each X-ray tube housing.
Place a label bearing the radiation symbol and the words "CAUTION –
Radiation Area” on the outside door to the CT room.
Regulation
• CT Law states that “only individuals
required for the radiographic procedure
shall be in the radiographic room during
exposures; and except for the patient, no
unprotected body parts of their bodies
shall be in the useful l beam.”
Other Safety Practices
• Use approved mechanical restraining
devices to hold children and other patients
whenever possible.
• If someone must assist by holding the
patient, ask an adult family member to
help.
• In emergencies, CT Law allows RTs to hold patients. If
you hold a patient, wear a lead apron and gloves. Keep
out of the primary beam. Direct the x-ray tube away
from you.
Radiation Safety is Not The
ONLY Safety in the CT Lab
• 1. Keep objects out of walkways.
• 2. Do not store items on overhead shelves
if there is a risk of falling.
• 3. Know where the fire alarm is.
• 4. Know where the nearest exit is.
• 5. Know where all emergency shutoffs are.
• 6. Post all emergency numbers.