hatch X-RAY, Operating Manual

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HATCH X-RAY Operating Manual
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Figure 12 : X-Ray - results
Once the exposure is completed (or aborted while
delivering), the X-Ray results screen displays the
actual values of kV, mA and ms sensed.
The Exposure Switch may be released once the
X-Ray results screen displays. If the Exposure
Switch is continued to be held, the next exposure
will not be initiated.
Results screen would show ABORTED rather than
DONE when the exposure procedure was aborted.
The results screen is shown for 10 seconds if not
interrupted by any key press (except the Exposure
Switch). The screen returns to Home screen and is
ready for the next exposure.
NOTE
The tube-head needs to cool down before proceeding to the next
exposure. This waiting period is decided by the exposure duration
selected for the last exposure. If an attempt is made to conduct an
exposure during this waiting period, the console displays a message
requesting the operator to wait for the remaining amount of time
required by the tube-head to cool down.
Dose is directly proportional to mA and mS for a given kV” Estimated Exposure
Values (kV, mA & ms) mentioned below are for minimum patient dose and can be
modified as per user requirement.
The inverse square law describes the principle of dose reduction as the distance
from the source increases. This assumes a point source. If radiation spreads
over a spherical area, as the radius increases, the area over which the dose is
distributed increases according to “A=4πr^2” where “A” is the area, “π” is “pi” and
“r” is the radius of the sphere. Therefore, the dose is proportional to the inverse
of the square of the radius. Thus, if you double the distance you reduce the dose
by a factor of four.
The reference dose can change ± 25% depending upon accuracy of dose meter
and accuracy of the kV, mA & mS delivered.