GE AMX-II User Manual

GENERAL ELECTRIC MEDICAL SYSTEMS AMX-il X-RAY UNIT
7-1576 SM A0654E
SEC.6 DIAGNOSTIC SOURCE ASSEMBLY; INHERENT FILTRATION
To meet HEW requirements, the haif-value layer of the useful beam at 80 KVP shall be not less than 2.3mm
aluminum. This test must be made of the diagnostic source assembly, at installation and whenever replacing
tube unit, insert, window, collimator mirror, or other absorption between source and patient.
NOTE: REFER TO DIRECTION 13894, PART li, SEC. 2 "RADIATION INSTRUMENTS" FOR
10,
11,
SPECIFIC INFORMATION ON DIFFERENT TYPES OF INSTRUMENTS.
Position radiation probe of a Dose measuring instrument so that the center of the active probe
area is 12 inches (304.8 mm) from the end of the collimator and centered in the useful beam.
Collimate down to area of probe using the light beam. Keep other equipment at least 4” (101.6 mm)
away from probe to prevent radiation scatter errors.
Use technic factors of 80 KVP; 20 to 48 MAS. MAS should be adjusted so that reading in step 5
is approximately 3/4 scale.
Remove the 1.0 and 2.0MM selective filters from the collimator.
Make an exposure and measure radiation (total R for integrating meters) with no added filters. This
represents 100% transmission level. Record readings and terminate exposure.
Place standard absorber 46-173632G1 in beam. Absorber must be in collimator accessory rails.
Repeat exposure and record reading.
Divide reading in step 6 by reading in step 5.
THEN FIXED FILTRATION
IF RATIO IS MUST BE
1. Greater than 0.5 Left as is.
2. Less than 0.5 Added (mandatory)
Filtration may only be removed if additional filtration was previously added. The amount of filtration
to be changed may be estimated as 0.5mm for each desired 0.05 change in ratio. For example, if
ratio is 0.48, a change of approximately .05, is desired, so add 0.5mm aluminum.
Fixed filters must be 1100 aluminum and should be mounted to the back of the mirror. Use a good
quality adhesive such as contact cement or epoxy. Since the filter will be at about 45° angle to the
beam use only about 0.7 of the thickness of aluminum that is calculated. Recheck before mounting
permanently (use tape for temporary mounting).
The 0.5 minimum ratio is mandatory, but above 0.5 ratio is not. However, above 0.57 there will be
a noticeable reduction in radiation, requiring higher technics to obtain the desired image density.
Record Data on F-3382, Test 13.
4-21

GE AMX-II Specifications

General

Brand	GE
Model	AMX-II
Category	Medical Equipment
Language	English