Volume 2 - Atomic Energy Regulatory Board

Y = ____________ cm % of TFD
Y’ = ____________ cm % of TFD
Tolerance : 2% of TFD
(b)
(c)
(d)
Difference in the dimensions of the radiation and optical fields
⎪X⎪ + ⎪X’⎪ =__________ cm
⎪Y⎪ + ⎪Y’⎪ =__________ cm
Tolerance : 3% of TFD
% of TFD
% of TFD
Difference between sums of lengths and widths of optical
and radiation field
⎪X⎪ + ⎪X’⎪ + ⎪Y⎪ + ⎪Y’⎪ =__________cm
Tolerance : 4% of TFD
% of TFD
Observe the images of the two steel balls on the radiograph.
Refer Table 1 for evaluating tilt in the central beam
Result : The tilt in the central beam is ______ o (degree).
Tolerance : Tilt < 1.5 o
5. FOCAL SPOT SIZE:
Large focus : Stated __________ mm x ____________ mm
: Measured _______ mm x ____________ mm
Small focus : Stated __________ mm x ____________ mm
: Measured _______ mm x ____________ mm
Result :
Tolerence : (i) + 0.5 f for f < 0.8 mm
(ii) + 0.4 f for 0.8 ≤ f ≤ 1.5 mm
(iii) + 0.3 f for f > 1.5 mm
Refer Table 1 for evaluating the focal spot size
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