Carestream DENTAL Nanoray CS 2400P, Руководство пользователя

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2) Leakage Dose
Scope
IEC 60601-2-65 203.12.4
Requirements
In the LOADING STATE, the AIR KERMA due to LEAKAGE RADIATION from X-RAY
SOURCE ASSEMBLIES, 1 m from the FOCAL SPOT, average over any area of
100 cm
2
of which no principal linear dimension exceeds 20 cm, when operated at the
NOMINAL X-RAY TUBE VOLTAGE under condition of LOADING corresponding to the
reference LOADING conditions, shall not exceed 0.25 mGy in one hour.
Results
The following exposure time tables were established with a unit equipped with a cone that
corresponds to a focus-to-skin distance of 200 mm (8 inch) respectively. When the leakage doses
have been measured with each cover type (default, rectangular 2x3, and rectangular 4x3), all the
results have been ND (Not Detected).
The raw data about the results is shown in the table below. (exposure time : 160 ms)
ND: Not Detected. Detection limit is 0.00001 mGy per exposure.
Result (Horizontal Plane, With Backscatter shield)
Direction
Default
type
Rectangular
2x3
Rectangular
4x3
[mGy/h] [mGy/h] [mGy/h]
0° ND ND ND
90° 0.060 0.060 0.060
180° 0.055 0.055 0.054
270° 0.090 0.090 0.090
Result (Vertical Plane, With Backscatter shield)
Direction
Default
type
Rectangular
2x3
Rectangular
4x3
[mGy/h] [mGy/h] [mGy/h]
0° 0.035 0.035 0.035
90° ND ND ND
180° 0.066 0.067 0.067
270° 0.057 0.057 0.058
ND: Not Detected. Detection limit is 0.00001 mGy per exposure.
Leakage Dose Permissive Range
70 kVp, 3.5 mA, 1.0 s (Max. Exposure Condition) At Focal
Spot to Distance 1 m
1 : 90 Duty Cycle
< 0.25 mGy/h