19.3 Equipment Acceptance Testing

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19.3 Equipment Acceptance Testing

• Your largest investment when establishing an
  office will be for Radiographic Equipment and
  Supplies.
• Sound business sense dictates that you should
  make sure the systems function properly.
• You should get what you paid for !!!!!

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Equipment Acceptance Testing

• The equipment may not be properly installed or
  calibrated.
• Improper installation or calibration can result
  in early x-ray tube failure and over exposure to
  your patient.
• Each wasted film is money lost and excessive
  radiation to the patient.

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Equipment Acceptance Testing

• Basic specification for radiographic systems
• Collimation within 2 of the SID used.
• Tube centering within 2 of the SID
• Accuracy of exposure within 5
• kVp Accuracy within 5
• Grid Centering within 2 degrees
• Timer Accuracy within 5

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Dangerous X-ray Machine

• This machine has not had proper service.
• The screws that mount the tube to the tube stand
  were loose.
• The tube could fall from the tube stand.

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Dangerous X-ray Machine

• This collimator is not approved for use on
  humans.
• The doctor replaced the collimator.

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mA and Timer Testing

• A digital rate meter or a timer testing tool may
  be used.
• This test tool has a motorized spinning top that
  records the duration of the exposure on the film.

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mA and Timer Testing

• It also has a stepwedge to measure the resulting
  mAs.
• Using different mA and Timer setting, the same
  mAs is used for multiple exposures.

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mA and Timer Testing

• Using a protractor, the exposure time can be
  measured.
• The Densitometer can be used to measure exposure.

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Beam Perpendicularity and Grid Centering

• This tool is used to check collimation and beam
  alignment.
• If the beam is not perpendicular to the Bucky or
  Grid, Grid cutoff will occur.

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Testing Beam Alignment

• This show the set up for testing beam alignment
  of the wall Bucky.
• The template and alignment tool are taped to the
  Bucky.

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Beam Perpendicularity and Grid Centering

• Testing a Wall Bucky requires taping the test
  tool to the Bucky.
• The lead balls need to be within the first circle
  to meet the 2 accuracy requirements.

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kVp Accuracy

• The kVp test cassette or a digital rate meter is
  used to test kVp.
• Exposures are made throughout the useful kVp
  range.
• The resulting film is then processed.

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kVp Accuracy

• The kVp Test Cassette or a digital rate meter is
  used to test kVp.
• Exposures are made throughout the useful kVp
  range.
• The resulting film is then processed.

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kVp Accuracy

• The black spots are read with the Densitometer.
• The line where the match are circled.
• The line is then plotted on the calibration chart.

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kVp Accuracy

• This is the test film on a new unit that was not
  properly calibrated.
• If the test had not been done, all of the films
  taken with technique charts would be over
  exposed.

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Other Acceptance Tests

• Checking the focal spot size, linearity of
  exposure and collimation will be discussed under
  Radiographic Equipment Quality Control.
• Radiation Health Physicist have the digital
  meters to rapidly test the equipment. They can
  give you a legal report.

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20.1 Film Storage Darkroom

• From the time of manufacture until the film is
  exposed and processed, it must be stored in a
  cool stable environment.
• Even after processing, it should not be exposed
  to heat or damp conditions.

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Film Storage

• All photographic films should be stored at less
  that 75 F. Ideally is should be 60 to 70.
• Film stored at high temperatures will be fogged
  by the heat. This will impact image quality.
• Be careful about offers of cheap film from
  disreputable dealers.
• In hot climates, keep air conditioning on even
  when office is closed.

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Film Storage

• The humidity is also important. It should be
  stored in an area with 40 to 60 relative
  humidity.
• It must be stored away from radiation sources and
  away from the processing chemicals.
• It must be stored on end as it is susceptible to
  pressure damage.
• Processing chemicals should be in secondary
  containment and stored in air tight containers.

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20.1 Darkroom Testing

• The temperature and humidity in the darkroom is
  very important. Same standards as storage.
• Keeping the chemicals in proper storage will
  reduce your exposure to fumes.
• Practice good chemical safety by wearing eye and
  skin protection when handling processing
  chemicals.

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Darkroom Testing

• The darkroom must be light tight so no white
  light is present during film handling or
  processing. Test the darkroom by closing the door
  and remain in the darkroom until your eyes are
  well adjusted (about 15 to 20 minutes).
• Look for light leaks around the processor, door
  and ceiling tiles.
• Check semiannually.
• Keep darkroom clean and dust free.

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Darkroom Safelight Testing

• Materials Needed
• Aluminum Stepwedge
• Piece of opaque material 4 x 10 (cardboard from
  film container works great)
• Densitometer
• Cassette with film.
• Frequency of test
• Semiannual or after bulb or filter change.

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Darkroom Safelight Testing

• Procedure
• Place stepwedge in the center of 8 x 10
  extremity cassette.
• Exposed the film.
• Take exposed film into the darkroom.

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20.2 Darkroom Safelight Testing

• Procedure
• Turn off the safelight
• Remove exposed film from cassette.
• Cover half of film with opaque material.
• Turn safelight on.

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Darkroom Safelight Testing

• Procedure
• Leave film on counter for two minutes.
• Process the film.
• Read densities with Densitometer.

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Darkroom Safelight Testing

• Standards
• At mid density, there should be less than 0.10
  optical density change between both sides of the
  film.
• Exposed film is more sensitive to fog.

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Darkroom Safelight Testing

• Example of faulty safelight and light leak.
• Fog destroys contrast
• Fog increased the speed so the image is flat and
  dark.

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Darkroom Safelight Testing

• Solutions
• Check wattage of installed bulb. Max 15W
• Check height from filter to work area. Must be at
  least 48.
• Make sure filter matches the film. Orthographic
  film is blue/green sensitive while other film is
  blue sensitive. Orthographic film will be fogged
  by wrong filter.

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Darkroom Safelight Testing

• Solutions
• After all of the above fails, try relocating the
  light farther away from work surface.
• The filters will not last forever, replace
  biannually.
• A rare problem is after glow of fluorescent
  lights.

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21.1 Automatic Film Processors

• Operation divided into six basic systems
• Roller Transport System
• Developer Recirculation
• Water Circulation
• Fixer Recirculation
• Replenishment Developer and Fixer
• Air Circulation (Dryer)

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Roller Transport System

• Purpose
• Transport Film
• Control Processing Time
• Control Replenishment Time
• Agitation
• Squeegee Action
• Help Prevent Overlap

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Developer Recirculation

• Purpose
• Develop Films
• Maintain Solution Activity
• Temperature Control
• Filtration
• Control of Recirculation
• Help Control Fixer Temperature

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Water Circulation

• Purpose
• Wash Films
• Help Control Developer Temperature
• Water Flow Control
• Agitation
• Help Control Fixer Temperature
• Keep Developer Drain Clean

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Fixer Recirculation

• Purpose
• Stops Development
• Clears the Film
• Hardens the Emulsion
• Agitation
• Maintain Solution Activity
• Constant Control of Recirculation

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Developer Fixer Replenishment

• Purpose
• Replenish chemical
• Maintain Solution Activity and Solution Level
• Control / Adjust Rate of Replenishment
• Check Replenishment Rates
• Prevent Siphoning of Replenisher

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Air Circulation/Dryer

• Purpose
• Dries the Film
• Temperature Control
• Constant Control of Circulation and Recirculation

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21.2 Processor Quality Control

• Purpose
• Monitor the development of the film to maintain
• Proper speed or density of the image
• Proper level of contrast of the image
• Minimize any background density on the film

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Starting Processor QC

• Have processor cleaned and fresh chemical
  delivered.
• Process a test strip for five consecutive days.
• Record the reading of each step. Average the
  reading from the strips to set a base line.

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Processor Quality Control

• Process of Processor Quality Control
• Check the temperature of the developer by use of
  a thermometer.
• Check water temperature.
• Check fixer temperature.
• If developer temperature is within 0.5 of
  specifications produce and process the
  sensitometric strip.

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Check Developer Temperature

• Proper development of the latent image is
  dependent upon
• Developer temperature
• Concentration of developer solution
• Time film spends in the developer
• Temperature must be to specifications

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Check of Water Temperature

• If the water is too cold, it will be more costly
  to heat the developer to operating temperature.
  If water is too warm, the developer will over
  heat.

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Check of Fixer Temperature

• The fixing of the image is dependent upon the
  fixer being within factory specification but is
  not as critical as developer temperature.

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Expose Sensitometric Strip

• The Sensitometer produces highly reproducible
  step wedge images used to monitor the performance
  of the developer.
• Using film set aside for processor quality
  control, expose both sides of the film with the
  Sensitometer.

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Process the Sensitometric Strip

• Always feed the film into the processor the same
  way and on the same side of the feed tray.
• Bromide drag and affect the image.

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Read the Sensitometric Strip

• A Densitometer is used to read the optical
  density of the strip.
• Read an area of unexposed film to check the base
  plus fog (BF) of the image.
• Then read the Speed and Contrast Steps.

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Read the Sensitometric Strip

• The amount of light passing through the image is
  the optical density of the image.
• Speed or Mid Density is the step closest a
  reading of 1.00 Base Fog or 1.20 OD
• Contrast or Density Deference is the deference
  between the steps closest to 0.25 Base Fog or
  0.45 and the step closest to 2.00 Base Fog
  or 2.20 OD.

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Graph the Results on the Processor QC Chart

• The processor should be checked before x-rays are
  taken on the first patient.
• If a problem exists, it must be corrected before
  processing patient films.

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Read the Sensitometric Strip

• The amount of light passing through the image is
  the optical density of the image.
• Speed or Mid Density is the step closest a
  reading of 1.00 Base Fog or 1.20 OD
• Contrast or Density Deference is the deference
  between the steps closest to 0.25 Base Fog or
  0.45 and the step closest to 2.00 Base Fog
  or 2.20 OD.

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Graph the Results on the Processor QC Chart

• The processor should be checked before x-rays are
  taken on the first patient.
• If a problem exists, it must be corrected before
  processing patient films.

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21.3 Processor QC Problem Solving

• Processor QC monitors the development of the
  film. These factors impact development
• Developer Temperature
• Time of Development
• Activity of the Developer
• Also the darkroom and film storage conditions
  will impact Processor QC.

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Base Plus Fog

• Any unexposed area of the film can be tested to
  determine the Base Plus Fog exposure level.
• Base Plus Fog is the level of pre-existing
  exposure exposure above the blue tint of the base
  of the film.

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Base Plus Fog

• Items that will impact the Base Plus Fog
  includes
• Condition of film storage after manufacture.
• Light integrity of the dark room
• The light spectrum from the safelight
• Temperature of the developer
• Contamination of the developer

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Speed Index or Mid Density

• This is the step closest to 1.00 plus BF or 1.20
  Optical Density. It corresponds to the middle of
  the useful exposure level on x-ray film.
• Factors that will impact the Speed Index include
• Developer Temperature Low Temperature will
  produce lower speed.

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Speed Index or Mid Density

• Developer Temperature High Temperature will
  produce increased speed.
• Fog level of the film Increased Base Fog will
  increase the Speed Index.
• Time spent in the developer Increased time at
  the correct temperature will increase speed.
• Activity of the developer under replenishment
  will lower the Speed Index

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Speed Index or Mid Density

• Activity of the developer under replenishment
  will lower the Speed Index
• Over replenishment will result in increased Speed
  Index.
• Contaminated Developer If fixer gets into the
  developer, the developer will be contaminated.

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Contrast or Density Difference

• Contrast Index is the difference between a step
  that produces a light shade of gray (0.25 O.D.
  BF) and the step that produces upper range of
  viewable light on an exposed film (2.00 BF)
• Step closest to 2.20 minus Step closest to 0.45
  equals the Contrast Index.

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Contrast or Density Difference

• Factors that will affect the contrast level
  include
• Fog level on the film
• Developer Temperature
• Development Time
• Contamination of the developer

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Processor QC limits

• The action level or results that should result in
  corrective steps being taken vary between
  national limits and those recommended by
  California.
• California recommends the tightest standards that
  will produce the most consistent image quality.

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Processor QC limits

• Developer Temperature 0.5 F (Ca) 1 to 2
  F.(US)
• BF 0.03 OD (California) 0.05 OD (US)
• Speed Index 0.10 OD (Ca.) 0.15 OD (US)
• Contrast Index 0.10 OD (Ca.) 0.15 OD (US)
• The California Standards are used in this course.

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Monitoring Frequency

• Daily when patients will be x-rayed
• Check fresh chemical levels
• Check that water flowing into wash tank and tank
  is full
• Check drive gears for wear.
• Check developer temperature when heater begins to
  cycle.
• Clean work surface and feed tray of processor.

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Monitoring Frequency

• Daily when patients will be x-rayed
• Clean cross over rollers or process two to three
  roller cleaning films.
• Perform Processor Sensitometry or QC
• Determine BF, Speed and Contrast Index
• Chart results
• Analyze results and take action as indicated.

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Monitoring Frequency

• At close of business each day or shut down
• Raise cover of processor about two inches
• Drain wash tank
• Semi-annual and at startup tests
• Immersion time or Speed of Processor Drive
• Water Flow Rate

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Water, Fixer and Q C

• Fixer Problems
• Contamination A very small amount of fixer
  getting into the developer will ruin or
  contaminate the developer.
• Improperly clearing of a film jam can cause this.
• Running rejected films to clean the rollers will
  contaminate the developer.
• Use new film or roller cleaning film.

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Water, Fixer and Q C

• Fixer Problems Under replenishment
• If the replenishment of the fixer is too low,
  the film will jam in the wash tanks or dryer
  because of a lack of hardening of the emulsion.
• The films will not dry properly.
• The film will be easily scratched and will not
  last as long in the files.

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Other Processor QC Tests

• Water Flow Meter Accuracy Measure water flow
  into processor. Criteria 5 Done quarterly
• Processor Transport Time Measure time from when
  the leading edge of the film enters the processor
  until leading edge exits the dryer. Criteria
  3 Done annually

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Conclusions

• Processor Q C monitors the developer.
• Developer replenishment, temperature and time the
  films spend in the developer are critical to
  consistent image quality.

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Processor Troubleshooting
Problem BF up BF Same MD up MD down DD down
Darkroom Fog X X X
Developer Temp Up X X X
Developer Concentration Too High X X X
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Processor Troubleshooting
Problem BF up BF Same MD up MD down DD down
Water Temperature Too High X X X
Developer Over- replenishment X X X
Developer Time Too Long X X X
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Processor Troubleshooting
Problem BF up BF Same MD up MD down DD down
No Starter after processor service X X X
Developer Contaminated X X X
Expired Time X X X
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Processor Troubleshooting
Problem BF up BF Same MD up MD down DD down
Developer Temperature too low X X X
Developer Concentration Too Low X X X
Under-replenishment X X X
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Processor Troubleshooting
Problem BF up BF Same MD up MD down DD down
Oxidized or exhausted Developer X X X
Inadequate Starter X X X
Exhausted Fixer X X X
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21.7 Hypo Estimator Test

• Tools needed
• Kodak Hypo Test Kit
• White Paper
• Processed Test Film
• Facial Tissue
• Frequency semiannual
• Caution solution will stain clothing

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Hypo Estimator Test

• Procedure
• Place a drop of the solution on any unexposed
  part of the film
• Let solution remain on film for two minutes
• Blot dry with tissue.
• Place film on the sheet of white paper.

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Hypo Estimator Test

• Procedure
• Compare the stain to template.
• Stain should match stain 1 or 2.
• Key point is to not let solution remain on film
  more than two minutes

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Hypo Estimator Test Results

• Stain 1 equals 1 µg/m²
• Stain 2 equals 2 µg/m² (Q C Standard)
• Stain 3 equals 5 µg/m²
• Stain 4 equals 12 µg/m²
• Excessive Hypo remaining on film means the film
  is not being washed properly.

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Hypo Estimator Test Results

• Potential Problems
• The water flow into the processor is not
  adequate.
• The squeegee on the cross over rollers is
  allowing too much fixer into the wash water.
• The wash water is not being changed often enough.
• If fixer in wash is high, water will be hazardous
  waste.

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The End

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