Copy_of_GP_Xray_Survey_Ser_04126-1004_Camp_Grayling_27APR2017_(002).xlsm

Site-Equip

MORTONAR: For more information please contact:

Major Arthur Ray Morton Chief, Health Physics Section arthur.morton@amedd.army.mil

Tripler Army Medical Center ATTN: MCHK-PVR (MAJ Morton) 1 Jarrett White Road Honolulu, HI 96859-5000

Phone (808) 433-2334 DSN 433-2334

FAX (808) 433-2440 DSN 433-2440

MORTONAR: Sort all remaining data to the right by MMCN

Clear Worksheet

Equip Checks

MORTONAR: Ensure that the following warning statement is displayed on the control panel containing the main power switch and is legible and accessible to view. "WARNING: This x-ray unit may be dangerous to patient and operator unless safe exposure factors and operating instructions are observed."

MORTONAR: For x-ray systems with AEC, indication will be made on the control panel when this mode of operation is selected. The following requirements will also be met.

(1) When the peak tube potential is 51 kVp or greater, the minimum exposure time for--

(a) Field emission equipment rated for pulsed operation will be less than or equal to the time interval equivalent to two pulses.

(b) All other equipment will be less than or equal to 1/60 second or the time interval required to deliver 5 mAs, whichever is greater.

(2) Either limit the product of peak tube potential, tube current, and exposure time to not more than 60 kilowatt-seconds per exposure or limit the product of tube current and exposure time to not more than 600 mAs per exposure. If the x-ray tube potential is less than 51 kVp, limit the product of x-ray tube current and exposure time to not more than 2,000 mAs per exposure.

MORTONAR: The exposure switch will be--

(1) A continuous pressure "dead man" type switch.

MORTONAR: Telemetric exposure switches controlling the tube circuit by wireless means will be used with caution. When using two or more telemetric timers within the same facility--

(1) Operate all timers on different frequencies.

MORTONAR: The technique factors to be used during an exposure shall be indicated before the exposure begins. If an automatic exposure control (AEC) is used, the technique factors that are set prior to the exposure will be indicated. For equipment with fixed technique factors, this requirement may be met by permanent markings. The indicated technique factors shall be visible from the operator's location, except in the case of spot films made by a fluoroscopist.

MORTONAR: The difference between the indicated tomographic angle and the measured angle will not exceed the manufacturer’s specifications or, in the absence of such specifications, will not exceed 5 degrees. The symmetry of the exposure angle about the midline will not exceed the manufacturer’s specifications or, in the absence of such specifications will not exceed

MORTONAR: The tomographic plane should be flat to within manufacturer’s specifications or, in the absence of such specifications, 3 mm for linear systems and 2 mm for other systems.

MORTONAR: The equipment will have the means to preset the cumulative on-time of the fluoroscopic tube. The timing device’s maximum cumulative time will not exceed 5 minutes without resetting. A signal, audible to the fluoroscopist, will indicate the completion of any preset cumulative on-time. While x-rays are being produced, this signal will continue to sound until the timing device is reset. Radiation therapy simulation systems may alternatively have a timer that--

(1) Indicates the total cumulative exposure time during which x-rays were produced.

(2) Is capable of being reset between x-ray examinations.

MORTONAR: Under table fluoroscopic equipment will have a shielding device(s) of at least 0.25 mm lead equivalent at 100 kVp. Such devices include--

(1) Overlapping protective drapes hung from the image receptor, and

(2) Hinged or sliding panels at the front of the table. When provided, a hinged or sliding panel should project at least 13 cm above the tabletop and will not interfere with the use of the table.

MORTONAR: The difference between the indicated tomographic angle and the measured angle will not exceed the manufacturer’s specifications or, in the absence of such specifications, will not exceed 5 degrees. The symmetry of the exposure angle about the midline will not exceed the manufacturer’s specifications or, in the absence of such specifications will not exceed

MORTONAR: The tomographic plane should be flat to within manufacturer’s specifications or, in the absence of such specifications, 3 mm for linear systems and 2 mm for other systems.

Leakage-EER

MORTONAR: Construct diagnostic source assemblies so that leakage radiation exposure at a distance of 1 m in any direction from the source will not exceed 100 mR (2.58 x 10-5 coulombs/kilogram (C/kg)) in 1 hour when the

MORTONAR: Construct components other than the diagnostic source assembly so that the radiation exposure will not exceed 2 mR (5.16 x 10-7 C/kg) in 1 hour at 5 cm from any accessible surface of the component when it is operated in an assembled x-ray system under any conditions for which it was designed. TB MED 521 4-2e

MORTONAR: Yes or No MORTONAR: Using the 450P and 1000 ms exposure time, the time response correction factor is about 0.85 MORTONAR: Construct diagnostic source assemblies so that leakage radiation exposure at a distance of 1 m in any direction from the source will not exceed 100 mR (2.58 x 10-5 coulombs/kilogram (C/kg)) in 1 hour when the x-ray tube is operated at the leakage technique factors. If the tube housing assembly’s maximum rated peak tube potential is greater than the diagnostic source assembly’s maximum rated peak tube potential, provide positive means to limit the maximum x-ray tube potential to that of the diagnostic source assembly.

MORTONA: The following EERs apply to fluoroscopic x-ray systems.

(1) Fluoroscopic equipment that is provided with automatic exposure rate control (AERC) will not be operable at any combination of tube potential and current that will result in an exposure rate in excess of 10 roentgens per minute (R/min) (2.58xl0-3 C/kg×min) at the point where the center of the primary beam enters the patient, except during recording of fluoroscopic images or when an optional high-level control (HLC) is provided.

(2) Fluoroscopic equipment that is not provided with AERC will not be operable at any combination of tube potential and current that will result in an exposure rate in excess of 5 R/min (1.29x10-3 C/kg×min) at the point where the center of the primary beam enters the patient, except during recording of fluoroscopic images or when an optional HLC is provided.

(3) Equipment with both an AERC mode and a manual mode will not be operable at any combination of tube potential and current that will result in an exposure rate in excess of 10 R/min (2.58xl0-3 C/kg×min) in either mode at the point where the center of the primary beam enters the patient, except during recording of fluoroscopic images or when an optional HLC is provided.

(4) If HLC is provided, the system will not be operable, in either AERC or manual mode, at any combination of tube potential and current that will result in an exposure rate in excess of 5 R/min (1.29xl0-3 C/kg×min) at the point where the center of the primary beam enters the patient, unless the HLC is activated. The system will have a special means to activate the HLC. The HLC will be operable only when the operator provides continuous manual activation. A continuous signal audible to the fluoroscopist will indicate that the HLC is activated.

(5) Fluoroscopic equipment manufactured on and after 19 May 1995 will be equipped with AERC if operable at any combination of tube potential and current that results in an exposure rate greater than 5 R/min (1.29xl0-3 C/kg×min) at the point where the center of the primary beam enters the patient. Provision for manual selection of technique factors may be provided.

(a) This equipment will not be operable at any combination of tube potential and current that will result in an exposure rate in excess of 10 R/min (2.58x10-3 C/kg×min) at the point where the center of the primary beam enters the patient, except during the recording of images from an x-ray image-intensifier tube using photographic film or a video camera when the x-ray source is operated in a pulsed mode or when an optional HLC is activated. Special means will be required to activate the HLC.

(b) When the HLC is activated, the equipment will not be operable at any combination of tube potential and current that will result in an exposure rate in excess of 20 R/min (5.16x10-3 C/kg×min) at the point where the center of the primary beam enters the patient.

(c) The HLC will be operable only when the operator provides continuous manual activation. A continuous signal audible to the fluoroscopist will indicate that the HLC is activated.

(6) Fluoroscopic radiation therapy simulation systems are exempt from the requirements set forth in (1) through (5) above concerning EERs.

MORTONAR: Construct components other than the diagnostic source assembly so that the radiation exposure will not exceed 2 mR (5.16 x 10-7 C/kg) in 1 hour at 5 cm from any accessible surface of the component when it is operated in an assembled x-ray system under any conditions for which it was designed. TB MED 521 4-7e EER Notes MORTONA: If the x-ray tube is under the table, position the ion chamber 1 cm above the table top, otherwise measure the exposure rate 30 cm from the input surface of the image receptor. In manual mode, set the contols to 90 kVp and 2 mA. Center the attenuation block over the ion chamber, and make an exposure and collimate the beam the dimensions of the attenuation block and verify the ion chamber is centered in the primary beam. Repeat measurement with 1/8 inch of lead over the attenuation block. Test high level control and pulsed modes (note the presence of an audible signal).

Tomo resolution MORTONAR: All tomographic systems will be capable of resolving a mesh pattern with 30 hole per inch (30 mesh) over the entire length in the plane of the cut. Specialized equipment should be capable of resolving a 50 mesh pattern.

MORTONA: Leakage Notes: To check diagnostic source assembly, close the shutters and add 1/8" of lead to block the primary beam. Make exposure measurements of approximately 1s duration at the maximum rated tube current for the maximum rated kVp. Measure the leakage radiation using a suitable ionization chamber at approximately 1 meter from the tube focal spot in 4 cardinal directions. At these settings, the tube can be operated only a limited number of seconds each minute or minutes per hour. This is the % on time per hour figure above or otherwise known as the duty cycle. Note that for many ion chambers the response time is greater than 1 second and either the exposure time will need to be increased or a time response correction factor applied or the meter is operated in integrated exposure mode. The radiation emitted from a component other than the diagnostic source assembly shall not exceed 2 mR in 1 hour at 5 cm from any accessible surface of the component. An example is the standby radiation from capacitor energy storage equipment without activating the exposure switch.

MORTONA: If the x-ray tube is under the table, position the ion chamber 1 cm above the table top, otherwise measure the exposure rate 30 cm from the input surface of the image receptor. In manual mode, set the contols to 90 kVp and 2 mA. Center the attenuation block over the ion chamber, and make an exposure and collimate the beam the dimensions of the attenuation block and verify the ion chamber is centered in the primary beam. Repeat measurement with 1/8 inch of lead over the attenuation block. Test high level control and pulsed modes (note the presence of an audible signal). TB MED 521 4-5e

RepLin

MORTONA: When the equipment is operated on an adequate power supply per the manufacturer’s specifications, the estimated coefficient of variation of radiation exposures will be no greater than 0.05 for any combination of selected technique factors. That is:

(See Equation 1) where: Xi = the ith exposure measurement _ = the average of the exposure measurements n = the number of measurements taken

MORTONA: When the equipment is operated on an adequate power supply per the manufacturer’s specifications and at any fixed tube potential within the range of 40 percent to 100 percent of the maximum, the following requirements will be met.

(1) If the equipment has independent selection of x-ray tube current (mA) and exposure time (s), the average radiation output (mR/mAs) at any two consecutive tube current settings will not differ by more than 0.10 times their sum. That is:

(See equation 2) where: X1 and X2 = the average radiation output values obtained at each of two consecutive tube current settings or at two settings differing by no more than a factor of 2 if the tube current selection is continuous.

(2) If the equipment has selection of tube current-exposure time product (mAs) only, the average radiation output (mR/mAs) at any two consecutive mAs selector settings will not differ by more than 0.10 times their sum. That is:

(See equation 2) where: X1 and X2 = the average radiation output values obtained at each of two consecutive mAs selector settings or at two settings differing by no more than a factor of 2 where the mAs selector provides continuous selection.

TB MED 521 4-3f

Output NCRP

mR/mAs

Output AAPM

mR/mAs kVpTimer

MORTONAR: Measurements 9-16

MORTONAR: Table is set up to analyze kVp for two conditions such as focal spot or mA

kilovolt peak (kVp) passed all conditions? FAILED

SHIMABUKULN: Paste Here Paste Keithley Triad Data from Radiographic window here