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300 Tasks for the Veterinary Assistant

there are breaks in the lead. Notify the inventory
manager so that piece of equipment can be
replaced. The assistant can help co‐workers by
making sure this gets done!
6. Individuals under 18 years of age and pregnant
women are never allowed in the room when
radiographs are being exposed.
7. Never enter a room denoted by a radiation hazard
symbol unless invited or it is known that a radiograph
is not being taken at that time. Close and if possible
lock the door to the radiation room, or indicate
radiographs are being taken by turning on a
warning light. This symbol denotes radiation is
used in that location
8. Reduce personal exposure by:
FIGURE 16.2 Lead gloves. • Staying out of the primary beam which comes
from the X‐ray tube housing and points down at
2. Lead gloves are used when a patient has to be held the table. Never place any human body part
for a radiograph (Figure 16.2). The lead protects within the primary beam as doing so substantially
the hands from radiation; however, it is never good increases exposure to radiation and subsequent
practice to allow a gloved hand to be within the damage.
primary beam. • Reduce scatter radiation. The radiography
3. The assistant can facilitate and “enforce” the wearing machine has an aluminum filter placed between
of PPE. When setting up for a radiograph, locate and the window of the X‐ray tube and the collimator
lay out all PPE; these are usually stored in the which absorbs soft X‐rays referred to as scatter
radiology room. Each person will need a lead apron, radiation. Scatter radiation is the interaction of
gloves, thyroid collar, and goggles. The dosimeters the primary beam with objects in its path. As the
are usually stored away from the radiography beam it hits the body part, cassette, and table top
machine. Gather each person’s dosimeter involved it bounces up in an outward projection. Scatter
in taking the radiograph. Make sure each person radiation is further decreased by using the
attaches their dosimeter on the apron, facing collimator to restrict the primary beam from
outwards at neck level. spreading beyond the cassette. Use the smallest
4. A dosimeter is a personal film badge worn facing cassette size to accommodate the anatomy being
out at the neck (Figure 16.1) or chest level on the radiographed. If restraining a patient, lean as far
outside of the apron. The dosimeter measures the away from the primary beam as possible.
level of exposure to radiation by the wearer. The 9. Use only the number of personnel necessary to
standard acceptable exposure is 0.005 sievert/year take the radiograph. Everyone else should evacuate
for occupational and background personnel. An the room or area.
annual report is sent to the practice for each 10. Taking exact site measurements using a caliper
individual badge. A dosimeter should never be (Figure 16.3) and subsequent setting of exposure
placed in direct sunlight or left in the heat of a car factors are absolutely essential to avoid retakes.
as it can give a “false” high radiation reading.
5. Take care of PPE. All lead‐containing safety Exposure factors are obtained from a tech-
nique chart that is prepared especially for that
equipment is hung up and never folded. Aprons radiography unit.
and thyroid collars have thin sheets of lead in them Position the patient correctly and confirm that the
and folding the lead will quickly cause a break. correct body part is being radiographed as per the
This break will expose the wearer to radiation. veterinarian’s orders. Tips for accomplishing this are:
Gloves should be put on a glove rack to ventilate, as
they get quite damp from sweat during procedures. • Anesthetize or sedate the patient if possible, as
Do not allow animals to chew or bite the gloves as this reduces struggling with a patient and avoids
the holes will expose the wearer to radiation. All movements that may require retakes.
lead‐containing equipment should be radiographed • Use positioning aids: sandbags, foam wedges
at least twice a year to examine for cracks in the (Figure 16.4), ropes, and radiopaque “V” troughs
shielding. Lay equipment across a cassette and to position patients correctly. These will also
expose; if there are dark spots or lines on the film improve quality by evening out the body.