Leak testing is an essential process in the pharmaceutical industry to ensure the safety and quality of the products. The purpose of leak testing is to detect any leaks or defects in the packaging, that could compromise the integrity of the product.
There are different methods of leak testing available, and the choice of method depends on various factors, including the type of packaging, the product being packaged, and the desired sensitivity of the test. Some of the commonly used methods for leak testing in the pharmaceutical industry are:
Vacuum Decay Technology
Vacuum Decay is a non-destructive container closure integrity test (CCIT) method that focuses on package integrity and detecting leak paths. Compared to manual inspection and other non-deterministic test methods, Vacuum Decay measurements offer deterministic and reliable test results to ensure package integrity. Vacuum Decay technology can accommodate a wide variety of packaging formats, including filled and sealed rigid, semi-rigid, flexible, non-porous or non-porous materials. This test works by placing packages in a well-equipped evacuation test chamber with an external vacuum source. Vacuum levels are continuously monitored to detect any deviations from predetermined targeted vacuum levels. A defect in the package can cause air to escape from the package into the test chamber. On the other hand, defect-free packages hold in air by maintaining a constant chamber vacuum level. Vacuum Decay technology has proven over the years to be one of the most practical and sensitive vacuum-based leak detection solutions.
MicroCurrent HVLD Technology
High Voltage Leak Detection (HVLD) is a non-destructive container closure integrity test (CCIT) for evaluating parenteral product packaging integrity. The concepts of quantitative electrical conductivity measurement are used in HVLD technology. HVLD is based on the fundamental nature of electric current. The package barrier must be non-conductive and prevent the flow of electricity, while the package contents must generally be able to carry voltage. The container is placed horizontally on the rotating stage. As the container rotates, a high voltage is applied to one side, and a ground probe is attached to the opposite side. If the package does not leak, the two container walls (high voltage and ground) offer complete electrical resistance and will not record significant current as it travels through the bottle. Breakdown resistance is encountered if there is a micro-leak or crack in one of the container walls and the current passes through. Examples of high-voltage leak detection technology applications include pre-filled syringes, ampoules, drug product cartridges, liquid-filled vials, and blow-fill-seal (BFS) containers.
Force Decay Technology
Force Decay is a quantitative leak detection method that works particularly well with low-headspace packaging. Non-porous materials such as foils, laminates, and films can be used for packaging types. Since it is a non-destructive test procedure, the sample packets are not harmed or changed. Packages do not need to be discarded away when the test is over; they can be added back to the batch. The test system use nested tooling to place the package in the same place and to prevent unmeasured extension of the package under test. Once the test is started, a vacuum is drawn onto the test chamber, which causes the package to expand inside the chamber. The ASTM F2338 vacuum decay leak test technique monitors vacuum levels during the test cycle to evaluate the package. The expansion of the package being tested applies force to the VeriPac force measurement system.
Volumetric Imaging Technology
OptiPac Leak Detection System is one of the deterministic non-destructive package integrity test solutions made especially for blister packs. The One-Touch Technology used in the design and engineering of OptiPac allows for a quick test cycle without the need for sample preparation or changeover. Depending on the size of the blister cavity, this unique technique can quickly identify defects less than 5 microns. Although the OptiPac system employs similar concepts to those used in a vacuum-based blue dye test, it uses controlled inputs and monitored outputs without the hassle and reliability issues of the dye ingress technique. To identify leaks, OptiPac use volumetric imaging technology to measure the motion of a blister package while it being vacuumed.
It is important to note that leak testing should be done at various stages of the packaging process, including before and after filling, and during storage and transport. Proper leak testing can help ensure that the pharmaceutical product is safe and of high quality, which is crucial for patient safety.