Maintaining Process Effectiveness
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Transcript of Maintaining Process Effectiveness
Maintaining Process Effectiveness
Regular Testing and Calibration
Regularly test and calibrate
Process equipments
Characterizing the magnitude, distribution, and reproducibility of the dose absorbed in a material of homogeneous density
Analytical equipments
Dosimetry systems
Dosimetry System Calibration
Calibrate
New batch of dosimeters
Calibration verification should be performed periodically at the facility
Analytical instruments
Measurement traceable to national standard
Dosimeters in a conditions similar to those in the actual production irradiator
Routine dosimeters
The level of measurement uncertainty at a specified confidence level should be known
Documented Procedure
Orientation of the product with diagrams
Product handling before, during and after irradiation
Documented procedure
Routine dosimetry
Required activities and functions for the irradiation of the products
Documentation for Dosimetry system
Type and batch number
Dosimeter manufacturer Dosimetry
system selected
Instruments used for analysis
Reference standard or transfer standard
Date
Dosimeter Calibration
Reference the calibration facility used
Documentation for Dosimetry performance
Dose rate
Temperature, Humidity. lightEffect of environmental conditions on dosimeter during irradiation and measurement
Energy spectrum
Measurement quality assurance plan used for the routine dosimetry
Measurements
Uncertainty associated with the measurement
Reference the method used to convert dosimetry measurements to absorbed-dose values in water
Records
Fulfill obligations to and requirements of the authorities
Provide documentary evidence showing that the product received correct treatment
The main purpose of Records
To settle disputes (if any)
Product Process record
Storage environment
Unique code identifying each product
Loading the product onto the irradiator system
Reception and inspection of product
Record of
Unloading the irradiated product from the system
Scheduling the irradiation
Inspection
checking of routine dosimetry, process parameters
Sign-off of any non-conformances
Approval for release and dispatch to the customer
Daily shift maintenance record
Record of
Shut downdetails
System Condition
Date & shift Personnel on duty - time in &out with signature
Record shutdown details with time. Record reason for shut downRecord action taken
Record various operational parameters such as Conveyor speed, cycle time, running time of the irradiator, total number of packages transferred
Technical details of each equipments employed for operation (exhaust fan, hydraulic motor, recirculation pump, etc) and values of other monitoring instruments such as survey meters, contamination monitors, conductivity, hydraulic pressure recirculation water temperature, pH, etc
Product log record
Record of
Requireddose
Details of product
ProductCustomer name,Unique ID of the box, Package number, Carrier no. If any,
Cycle timeConveyor speed
Dosimeter Dosimeter number
ProductProcessing
Package inDate and time
Package out Date & time
Irradiation Control record
Product type
Time
Absorbed doses for products processed
Date
Record ofLoading diagrams
Process parameters of specific production runs
Reference the calibration of processing equipment
Reference the calibration of dosimetry systems and other analytical instruments
Dosimetry record
Calibration of Dosimetry equipments
Calibration of dosimeters
Absorbed dose for each specific production runs
Record of
Maintenance of the dosimetry equipment
Facility record
Any special conditions of the facility that could affect the absorbed dose to the product
Date the product is processed and the starting and the ending times of the irradiation
Each lot of product that is processed with unique identification number
Record of
Name of the operator
Record for Review and Approval
Periodic audit of all documentation
Names of authorized personnel who issued the certificate
Certificate for delivery of the dose to the product for each production run.
Record of
Retention of Records at the facility
Certificate of irradiation
Time specified by relevant authorities
Dose calibration documents
Copies of shipping documents
Copies of receiving documents.
Routine Dosimetry data
Irradiation control records
For each production run, retain record at the facility for inspection
Retain the records for a period
References
Guidelines for the Development, Validation and Routine Control of Industrial Radiation Process.IAEA Radiation Technology Series No.4 (2013)
ISO 11137:2006 “Sterilization of Healthcare Products – Radiation”Part 1: Requirements for development, validation and routine control of a sterilization process for medical devicesPart 3: Guidance on dosimetric aspects
Trends in radiation Sterilization of Health Care Products. IAEA, STI/PUB/1313 (2008)
ISO/ASTM 51649 “Standard Practice for Dosimetry in an Electron BeamFacility for Radiation Processing at Energies Between 300 keV and 25MeV”
ISO/ASTM 51702 “Standard Practice for Dosimetry in Gamma Irradiation Facilities for Radiation Processing”
ISO/ASTM 51261 “Standard Guide for Selection and Calibration of Dosimetry Systems for Radiation Processing”
Worked example
Example. 1: The sterilization dose specified for a product is 25 kGy and maximum dose is specified as 40 kGy. Data from a dose mapping exercise at the irradiation facility for the product shows dose at Reference position - 30.5 kGyminimum position - 26.5 kGymaximum position - 37.0 kGyFind out the minimum and maximum reading that is permissible for the routine dosimeter during routine processing of the product at the facility?
Answer.Minimum reading of the routine dosimeter
= Dose at the reference position X sterilization dose Dose at the minimum position= 30.5 x 25 kGy = 28.8 kGy 26.5
Maximum reading of the routine dosimeter= Dose at the reference position X sterilization dose Dose at the maximum position
= 30.5 x 40 kGy = 33.0 kGy 37.0
Therefore the minimum and maximum permissible reading of the routine dosimeter to register for the load to meet the specification are 28.8 kGy and 33 kGy respectively.
Worked example
Example. 2: The sterilization dose specified for a product is 25 kGy and maximum dose is specified as 40 kGy. If the routine permissible range is from 27 kGy to 35 kGy, find out the absorbed dose at minimum and maximum dose position in the product if the routine dosimeter registers a reading of 31 kGy?
Answer.Absorbed dose at the minimum dose position
= Sterilization dose X Routine dosimeter reading Minimum routine permissible reading= 25 x 31 kGy = 28.7 kGy 27
Absorbed dose at the maximum dose position= Maximum specified dose X Routine dosimeter reading maximum routine permissible reading= 25 x 31 kGy = 35.4 kGy 35
Therefore the minimum and maximum absorbed dose corresponds to the above routine dosimeter reading are 28.7 kGy and 35.4 kGy respectively.
Questions
Multiple Choice 1. Penetration of electrons depends on:
A. Current of electron beam, B. Electron energy, C. Speed of conveyor.
2. Radiation sterilization is performed according to: A. ISO 11134, B. ISO 11137, C. ISO 11135.
3. What does “dose mapping” mean? A. Determination of minimum dose B. Determination of maximum C. Measurement of dose distribution
4. Which dosimeter is used for monitoring of radiation processing of products? A. Reference dosimeter B. Routine dosimeter C. Transfer standard dosimeters
5. In radiation processing application, calorimeter is used as A. Primary dosimeter B. Transfer standard dosimeter C. Routine dosimeter
6. For absorbed dose measurements for radiation sterilization, dose is referred in A. Water B. Air C. Graphite
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Questions
1. Which standard do you follow for the sterilization of health care products?
2. Which standard do you follow for the selection of dosimetry systems?
3. Which standard do you follow for the calibration of dosimetry systems?
4. Which standard do you follow for estimating uncertainty in your dosimetry systems?
5. Name few reference standard dosimeters for calibration gamma irradiation facilities
6. What are the differences between reference standard and routine dosimeters?
7. What are the required procedures to validate the radiation processing of products?
8. How do you achieve measurement traceability for your dosimetry systems?
9. What are the roles of dosimetry in the validation of radiation processing?
10. How do you ensure quality assurance during routine production of radiation
processed product?
11. Name few routine dosimeters used in the range of 400 Gy to 1 kGy dose range for
food irradiation facilities.
12. How do you calibrate 10 MeV electron beams?
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Questions
13. Name few routine dosimeters used in electron beam irradiators.
14. What are important differences between the dosimetry of electron beam facility and
gamma irradiation facility?
15. What are the main aims of carrying out dose mapping in IQ, OQ and PQ?
16. Why do you require different dosimeters during different stages of validation process?
17. What are the important environmental conditions that affect the performance of the
dosimeters during its applications?
18. How do you ensure accuracy of measurement?
19. How do you correct systematic error in your dosimetric measurement?
20. What are operational and performance qualifications?
21. How is dose mapping in operational qualification is different from performance
qualification?
22. Which standard do you follow for dose mapping during validation?
23. Which standard do you follow for the validation of radiation processing gamma
irradiator?
24. What standard do you follow for the validation of electron beam irradiator?
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