Installation issues as well as calibration, manufacturer documentation and balance specification verification will be covered under Installation Qualification protocol. In case the IQ was completed successfully and the IQ report was approved, the Operational Qualification can begin based on Operational Qualification protocol. Routine testing, weighing tolerance, SOP’s and other balance operation related issues will be covered as part of the Operational Qualification. The balance should not be in usage before Validation stage was completed successfully, documented and summarized.
Balance routine testing
Routine testing for balance should be defined, documented and performed in order to keep balance data integrity, product safety and product quality. Under ISO 9001 part 7.6 (Control of monitoring and measuring devices) which is a very basic standard for the Biotechnology, Pharmaceutical and Medical Device industries, it was mentioned that measuring equipment shall be calibrated or verified at specific intervals against measuring standards traceable to international or national measurement standards. After balance installation, calibration and qualifications stages, as part of balance routine operation, routine testing should performed by the user to assure high integrity, reliable, traceable and accurate weighing results in order to minimize weighing errors and to increase product quality and safety.
Balance calibration is usually performed once a year, therefore the balance status between calibrations is unknown. Balance routine tests should be defined based on Risk Assessment. Routine tests should be established by the user, controlled and documented under relevant policies and SOP’s. Modern balance models offer built-in calibration system which may minimize environmental effect on balance accuracy level as well as reduce routine testing frequency. The reference weight that installed on the balance should be in calibrated state (by external qualified laboratory). There are several additional balance measurements parameters such as balance sensitivity, eccentricity, non linearity and repeat ability. Balance repeat ability may be affected from several factors such as balance type/model, balance configuration, gross load, operator weighing skills, ambient conditions, size and shape of the weighted object/material and others. Routine tests’ frequency should be determined based on Risk Analysis and balance usage frequency. The higher the impact of the weighing results, the higher the balance accuracy and routine testing frequency. Routine balance testing results should be compared to control and action limits that will be established by the user. In case control limits were triggered, usually no immediate action is required but the following balance performance should be inspected and investigated. In cases action limits were triggered, the user should not use the balance till the root cause investigation was performed and the balance malfunction was detected and fixed.