Manual Visual Inspection is an important step in pharmaceutical manufacturing which aids in the detection of various formulation defects. The defects are observed in the all types of formulations viz. tablets, capsules, injectables etc. To effectively observe the defects there are many requirements w.r.t. trained and qualified operators, Inspection belt, lighting, background etc.

In this series on pharmaceutical product inspection, we shall be discussing various aspects of manual visual inspection serially. Previously, we had already discussed about the “Lighting requirements for Manual Visual Inspection of Pharmaceuticals” and “Inspection Rate for Manual Visual Inspection of Pharmaceuticals”.

Accordingly, this article shall provide information on container handling and movement during manual visual inspection.

Container Handling and Movement: During inspection of drug products, proper container handling is really important for proper detection of defects and any particle contamination. During inspection, the liquid product inside the container shall be gently swirled or inverted. This rinses any particles from the upper inner surfaces of the container and the closure and puts them into motion. However, it shall be ensured that air bubbles are not introduced during the process. The air bubbles can appear as particles and thus interfere with the detection of offending particles.

How many containers can be held together for inspection?

Holding many containers by hand at once should be avoided, as it is difficult to obtain a complete view of all container surfaces and contents. Container motion is also helpful for identifying small container defects such as cracks or chips. A tool that holds multiple containers for consistent presentation can be useful when performing inspection.

Magnification: Some inspection processes use a large magnifier to increase image size and thus increase the probability of detecting and rejecting containers with defects near the threshold of detection. Although magnification can be useful for critical examination of a portion of the container, it does not often lead to increased overall detection rates for defects of interest. This may be due, in part, to the added eye strain that often results from use of magnification. Magnification is not recommended for use during routine inspections. It can be helpful for critical examination of a small number of units, as may be needed during an investigation.