Questions & Answers: Semi-Automated Visual Inspection

In a webinar on semi-automated visual inspection of parenteralia many basic questions regarding visual inspection and also specific questions with regard to semi-automated inspection were asked and answered.

Q: Our product is a non-transparent oil emulsion in 250 ml and 500 ml bags. Is a semi-automated inspection with cameras conceivable?
A: Another method for particle detection should be used. The visual inspection of such a 500 ml bag is almost impossible. To ensure that the bag is free of particles another method like filtration should be used.

Q: A question regarding the qualification of a new production line. How to proceed if you have neither a qualified system nor qualified staff? Both types of qualification need each other.
A: Qualified employees for manual control must be available. Using them, the process of semi-automated visual inspection can be qualified. It is the same if a fully automated system is to be qualified.

Q: Regarding the design of a semi-automated machine: Are colors other than black and white allowed? As in manual testing. Would grey be better? Is a white background enough?
A: Black is the best color here. Once in terms of light reflections and operator fatigue. Grey would also work. In Annex I, there is no specific requirement for the background colour of a semi-automated system.

Q: What is required for the certification of operators and how can eye breaks / inspection times be documented?
A: Operators should have an ophthalmologic certificate (80% normal vision) and a qualification that proves that they can sort out the required defects. Pause times / inspection times should be recorded using log on / log off of the operator; manually by hand or automated.

Q: What is an optimal illumination level (in lux) for the inspection of plastic containers in semi-automated systems? And is there a type of illumination you prefer?
A: Higher illuminance levels than glass, but it is up to you to determine the best illumination for this. Definitely higher than 3750 lux. LED lighting may be preferred.

Q: Should the smallest particle sizes determined by a Knapp study be systematically included in the test kits for qualification?
A: Yes.

Q: What is your opinion / experience of using polarized lenses in a semi-automated system?
A: Not good. The naked human eye is best and this is what is expected.

Q: Is that correct that the visual inspection in front of black and white background on a fully automated system should not exceed 2 seconds?
A: No. The speed of the semi-automated conveyor belt should not be too fast. The maximum speed should mathematically be no less than 2 seconds per object in the inspection area for the operator.

Q: Are there any special requirements for semi-automated inspection for Japan?
A: No. Make sure to sort out all particles and cosmetic defects when you deliver to Japan.

Q: For a comparative semi-automated versus manual inspection study, do the test kit sizes have to be the same?
A: Yes.

Q: Is that correct that after a 100% semi-automated inspection is completed, a manual inspection based on ISO 2859-1 should be performed?
A: Yes, i.e. sampling based on ISO 2859-1 and manual testing of the samples. The size of the AQL sampling depends on the batch size. Inspection Level II should be used.

Q: How often should manual inspection operators be qualified (note: requalified)?
A: At least once a year.

Q: The settings of the semi-automated system (illumination, rotation speed, etc.) should be selected in such a way that a sufficient inspection process is guaranteed without adversely affecting the physico-chemical properties of the product. How do you ensure this during qualification?
A: For this purpose, you need to perform a stability study, e.g. with the validation batches, and show that your inspection process has no influence on the product quality.

Q: Do you have special experience with different inspection angles in semi-automated systems when testing liquids or lyophilized products.
A: Through the lens of the semi-automated machine, the inspection angle should not influence the inspection. The lens should be placed so that the operator can see the complete unit. For lyophilized products, the only difference is that the inspection time for the operator should be shortened because visual inspection of the white powder will cause eye fatigue more quickly.