RaySafe Xi - Manual (Page 36)

Figure 4. kV and kVp
Table: Active compensation on kV measurements
Sensor Filtration kV/kVp
r/f low Max. 1 mm Cu or equivalent kV
r/f high Max. 1 mm Cu or equivalent kVp (when signal level is high enough)
Mammography:
Mo/Mo 25 – 35 µm Mo kV (choose “paddle” or “no paddle”)
Mo/rh 25 – 30 µm rh kV (use 2mm al filter)
w/rh 55 – 60 µm rh kV (choose “paddle” or “no paddle”)
w/al 0.65 – 0.75 mm al kV (choose ”paddle” or ”no paddle”)
w/al s (scanning) 0.5 mm al total filtration kV (use 2mm al filter)
use a kVp delay on machines with a slow rising output. 150 ms on dental single phase machines and 1000 ms
on a fluoroscopy machine is recommended.
kV is available for r/f and mammography detectors.
NOTE! When selecting the Mo/Mo W/Rh, or W/Al mammography beam quality, you also get at choice
of “paddle” or “no paddle” which only applies if the kV measurement is going to be made with
or without a paddle in the beam and does not affect dose or HVL measurements.
tIMe
the raysafe Xi measures time from the start trig (may be adjusted with the trig level setting) until the signal
falls below 25 % of the peak (50 or 75 % if adjusted with the trig level setting). at low dose rates (about 1 %
of the max dose rate for the active sensor), the 25 % end level is changed to a low level (about the lowest
measurable dose rate for the active sensor).
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raysafe Xi user Manual – Measurement definitions