Measurement performance verification – RaySafe i2 Installation Manual User Manual
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RaySafe i2 Installation and maintenance manual – measurement performance verification
meASURement PeRfoRmAnCe veRIfICAtIon
the purpose of this test is to verify the measurement performance of dosimeters using scattered radiation from
diagnostic X-ray units. Unfors RaySafe recommends the following arrangement:
CAUTION:
Do not expose yourself to X-ray radiation.
you need the following equipment to perform a measurement performance verification:
• A reference instrument measuring H
p
(10) (for example a known reference dosimeter, or some other meter).
• two 20x20x5 cm
3
PmmA phantoms or similarly scattering material.
• dosimeters for test
• Real time display
follow the instructions below:
1. Place one of the phantoms on the patient support.
2. Place the other phantom at the same height, but 0,5 m on the side from the first one.
3. Place the additional H
p
(10) meter on the center of the second phantom.
4. Place the dosimeters that have to be tested on the phantom around the additional H
p
(10) meter.
5. expose with a field covering the first phantom, at 80 kvp set, 4 mA, for 60s. If needed, adjust the distance
or the mA to get a dose rate of about 1 – 10 mSv/h.
6. Compare the dosimeter readings with the additional H
p
(10) meter. Readings should be within specifications
for the different meters.