processor quality control problem solving
Download
Skip this Video
Download Presentation
Processor Quality Control Problem Solving

Loading in 2 Seconds...

play fullscreen
1 / 62

Processor Quality Control Problem Solving - PowerPoint PPT Presentation


  • 58 Views
  • Uploaded on

Processor Quality Control Problem Solving. Midterm Topic 2. 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.

loader
I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
capcha
Download Presentation

PowerPoint Slideshow about ' Processor Quality Control Problem Solving' - mayten


An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
processor quality control
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.
check developer temperature
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
check of water temperature
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.
check of fixer temperature
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.
expose sensitometric strip
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.
process the sensitometric strip
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.
read the sensitometric strip
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 (B+F) of the image.
  • Then read the Speed and Contrast Steps.
read the sensitometric strip1
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.
graph the results on the processor qc chart
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.
21 3 processor qc problem solving
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.
base plus fog
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.
base plus fog1
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
speed index or mid density
Speed Index or Mid Density
  • This is the step closest to 1.00 plus B+F 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.
speed index or mid density1
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
speed index or mid density2
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.
contrast or density difference
Contrast or Density Difference
  • Contrast Index is the difference between a step that produces a light shade of gray (0.25 O.D. + B+F) and the step that produces upper range of viewable light on an exposed film (2.00 + B+F)
  • Step closest to 2.20 minus Step closest to 0.45 equals the Contrast Index.
contrast or density difference1
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
processor qc limits
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.
processor qc limits1
Processor QC limits
  • Developer Temperature: ± 0.5° F (Ca); ± 1 to 2° F.(US)
  • B+F: + 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.
monitoring frequency
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.
monitoring frequency1
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 B+F, Speed and Contrast Index
    • Chart results
    • Analyze results and take action as indicated.
monitoring frequency2
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
chart 1
Chart 1
  • Problem solving:
  • Start with developer temperature
  • Then look at Base + Fog
  • Then look at Speed Index
processor within limits chart 1
Processor within Limits Chart 1
  • With proper developer temperature, reasonable volume of films processed and proper rate of replenishment the processor should stay within limits.
  • After cleaning the speed will increase due to fresh developer. This is normal.
processor within limits chart 11
Processor within Limits Chart 1
  • Trends can be monitored when the processor is within limits.
  • Continued lower than normal speed index is a symptom of under replenishment. A slight increase in replenishment may be warranted
processor within limits chart 12
Processor within Limits Chart 1
  • If you are under replenishing the chemicals and the case volume drops, the developer may go bad.
  • Continued high reading means over replenishing of the developer.
chart 2
Chart 2
  • Problem solving:
  • Start with developer temperature
  • Then look at Base + Fog
  • Then look at Speed Index
problem 1 chart 2
Problem #1 Chart 2
  • Symptoms:
    • B+F and Speed are up
    • Contrast is down
    • Developer Temp normal
  • Diagnosis:
    • Problem with dark room with safelight or light leak in darkroom.
problem 1 chart 21
Problem #1 Chart # 2
  • Solutions:
    • Check bulb wattage in safelight
    • Check for light leaks
    • Check for damage to filter in safelight.
    • Check fluorescent fixture for after glow.
    • Move safelight
chart 3
Chart 3
  • Problem solving:
  • Start with developer temperature
  • Then look at Base + Fog
  • Then look at Speed Index
problem 2 chart 3
Problem #2 Chart #3
  • Symptoms:
    • Gradual decrease in Speed Index
    • Temperature within limits
    • B+F within limits
  • Diagnosis:
    • Low volume of films processed
    • Under replenishment
problem 2 chart 31
Problem #2 Chart #3
  • Solutions:
    • Run two to three fresh 14”x17” films or roller cleaning films each day through processor. Do Not run rejected films as they will contaminate the developer with residual fixer.
problem 2 chart 32
Problem #2 Chart #3
  • Solutions:
    • Slightly increase the developer replenishment rate until the volume of cases increase.
    • Check for low levels of chemical in processor tanks.
chart 4
Chart 4
  • Problem solving:
  • Start with developer temperature
  • Then look at Base + Fog
  • Then look at Speed Index
problem 3 chart 4
Problem #3 Chart 4
  • Symptoms:
    • Gradual rise in speed and contrast
    • Sudden drop in Speed, Contrast and Developer temperature
  • These are two separate but common problems.
problem 3 chart 41
Problem #3 Chart 4
  • Symptoms: Gradual rise in speed and contrast.
  • Problem: If the volume of x-ray films processed each day increases significantly, the developer will be over replenished.
  • Solution: If film processing volume remains high, reduce replenishment .
problem 3 chart 42
Problem #3 Chart 4
  • This is not typically recommended because a drop in film volume will quickly result in under replenishment.
  • Other factors that can cause this increase:
    • a new box of control film that is a little faster. Change aim if speed changes with the new box of control film.
problem 3 chart 43
Problem #3 Chart 4
  • Other factors that can cause this increase:
    • a drop in the drive speed will cause the film to remain in the developer longer. This can be the result of a bad bearing, or roller or problem with the drive motor.
    • Always check the developer temperature first.
problem 4 chart 4
Problem #4 Chart 4
  • Problem 2 Symptoms:
    • Drop in developer temperature, speed and contrast.
  • Diagnosis: Developer Temperature Control Problem or the test was done before the developer reached operating temperature.
problem 4 chart 41
Problem #4 Chart 4
  • Solutions:
    • If the developer temperature was checked before the strip was run, the problem would have been addressed without the need for the film.
    • It is very important to know how long it takes the processor to warm up in the morning. Time varies from 20 to 45 minutes.
problem 4 chart 42
Problem #4 Chart 4
  • If some time has passed between the check of the developer temperature and processing the control strip, the following must be considered:
    • The developer thermostat, developer heater or fuse for the heater has failed.
    • Most processor will have a light that blinks when the heater is on. If the light remains out, the heater is not working.
problem 4 chart 43
Problem #4 Chart 4
  • If the water coming into the processor is too cold, the developer heat controls will:
    • Fail prematurely because of excessive needs for heat.
    • You will use more power to maintain the developer temperature.
chart 5
Chart 5
  • Problem solving:
  • Start with developer temperature
  • Then look at Base + Fog
  • Then look at Speed Index
problem 5 chart 5
Problem #5 Chart 5
  • Problem: Repeated increases in developer temperature, Speed Index and Contrast Index
  • Solutions: The developer temperature is controlled by the heater, thermostat and water temperature on most processors. The problem will generally be within these systems.
problem 5 chart 51
Problem #5 Chart 5
  • If the water was not turned on, the developer will over heat.
  • If the water was turned on but the water flow control valve is defective or clogged, the developer will over heat.
    • Test control valve every six months
    • Use a water filter to control mineral content of water.
problem 5 chart 52
Problem #5 Chart 5
    • The thermostat may have failed closed resulting in the over temperature condition.
  • The film may have been run with the processor set at the wrong speed and developer temperature.
    • Medical facilities use extended processing for mammography to reduce radiation by increasing speed and improve contrast.
problem 5 chart 53
Problem #5 Chart 5
  • IF the Speed Index, Contrast Index and Base + Fog increased with normaldeveloper temperature, the drive system is faulty.
chart 6
Chart 6
  • Problem solving:
  • Start with developer temperature
  • Then look at Base + Fog
  • Then look at Speed Index
problem 6 chart 6
Problem #6 Chart 6
  • Symptoms: Speed Index and Contrast Index continue to fail with normal developer temperature and processing speed. The processor is fine right after service.
  • Solution: The processor is under used due to very low exam volume.
problem 6 chart 61
Problem #6 Chart 6
  • The developer in the processor tanks will oxidize if fresh solutions are not added to the tank. As developer ages, it turns brown.
  • The replenishing tanks should be air tight.
  • To avoid this problem the following may be done:
problem 6 chart 62
Problem #6 Chart 6
  • Every other day or daily turn on the processor and run two or three 14” x 17 films to pump fresh chemicals into the tanks.
  • When you turn on the processor check chemical levels in the tanks. Evaporation is also a problem when film volume is low.
problem 6 chart 63
Problem #6 Chart 6
  • Use flood replenishment to pump fresh chemicals into the tanks. Every few hours, fresh chemicals are pumped into the processor.
  • This will maintain the proper chemical levels in the tanks and avoid chemical deposits on the rollers.
water fixer and q c
Water, Fixer and Q C
  • Fixer Problems:
    • Contamination: A very small amount of fixer getting into the developer will ruin or contaminatethe 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.
water fixer and q c1
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.
other processor qc tests
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
conclusions
Conclusions
  • Processor Q C monitors the developer.
  • Developer replenishment, temperature and time the films spend in the developer are critical to consistent image quality.
ad