Package Integrity: The single, most effective test for product quality

Author, Oliver Stauffer

Vacuum Decay, The Ultimate Solution

Package quality has never been simpler or more effective to achieve. It is the single most critical packaging attribute to protect the product throughout its lifecycle, beyond the walls of the manufacturing operation. Package integrity protects the product from oxygen, moisture, bacteria, and all other environmental contaminants. Defects are most often systematic and can be effectively eradicated with proper testing regimes focused on critical attributes. Package integrity can be related to the materials, processes, or even the people involved. If there is a systematic issue related to any of those three categories, it can easily lead to an ineffective packaging process in any operation. The package is there to protect the product. Deploying simple, practical, and effective integrity-testing solutions to ensure package quality has an impact that reaches far beyond the manufacturing operation.

Most primary package applications require a controlled headspace, and this can be tested very practically using vacuum decay solutions. Vacuum decay is a simple leak-test method where the package or area of interest is placed under vacuum and monitored for a short time. Any decay in the vacuum level means that there is a leak. A complete package can be placed into a test space, or a specific portion of the package can be tested using a test fixture. Bottle and container applications can be tested with a fixture that focuses solely on the closure area. Essentially, any sealed package format is able to be tested using this vacuum-decay approach.

Vacuum decay also works for liquid applications. At its most basic level, vacuum decay is attempting to draw gas from the container. In an application where liquid may have come in contact with the defect on the inside of the package, deploying a deep vacuum solution that vaporizes the liquid is the most practical application. In this case, the vacuum level of the test is below the vapor pressure of the test liquid. A leak is detected by the change in vacuum in the test chamber due to liquid vapor leaking from the package into the said chamber.

This technology has many practical benefits that greatly improve the quality insights a test method can provide.

• Tests the most critical, physical attributes of a package-barrier integrity

• Provides traceable, quantitative data

• Non-destructive and repeatable (more on that to come)

• Test methods are globally transferable and recognized by regulatory bodies

• Simple, fast, and effective

Flexible package testing is one of vacuum decay’s primary highlights. In most cases, the use of a flexible test chamber provides multiple benefits. It provides universal flexibility for different package format sizes. The flexible membrane conforms to the package to optimize test sensitivity. The material naturally conforms to the package, preventing any additional stress or markings. As with most vacuum decay applications, it can be deployed in a 100% inspection setting.

The benefits of a non-destructive method are numerous. If a sample is tested with a destructive method, the results generally cannot be recreated. A non-destructive method leaves the sample unadulterated and intact. After a test is completed, the result can be fully inspected and understood. Further inspection on a pristine test sample can provide significantly more information than a single destructive test. While many destructive tests are only pass or fail in nature, vacuum decay provides a variable result that relates to the size of leak a package has.

Vacuum decay test methods are accurate and sensitive. The variable test result allows for test-method sensitivity to be adjustable. Longer, more sensitive test cycles can reach the 1-micron defect detection limit. Newer, shorter test cycle algorithms make it possible to detect 5-micron defects in under five seconds. New vacuum-decay technologies are optimized for leak tests on products and to test sensitivities never before possible.

Quality sampling is fundamentally risk based. A statistically supported sampling plan often requires beginning of batch result data , interval testing, and end of batch results. Using basic statistical tools like Squeglia’s formula to calculate an appropriate sampling plan, the risk associated with the application increases as does the sampling rate. Vacuum decay is a practical solution for increased sampling plans. For high-risk applications, the non-destructive nature also yields significant benefit. Tested samples can be further analyzed and confirmed before additional action is taken. A destructive method of testing for a high-risk critical attribute produces unverifiable results.

Automation of vacuum decay solutions allows for a higher performance sampling plan. Automating line sampling can provide increased test results more frequently and captures those test results through a line-data management system. Vacuum decay’s non-destructive nature allows tested package formats to be reintroduced to the line. Most production lines test less than 0.5% of production output. Increasing the product tested to 3% for a similar batch size reduces the risk of systematic defects by 10 times when using a zero defect acceptance sampling approach.

Some operations have deployed vacuum decay to 100% inspect the quality of bad batches put on hold from distribution. Vacuum decay is fast, and the non-destructive test allows the batch in question to be processed and all tested samples can be fit for sale. Those same sites now use vacuum decay solutions to prevent the risk of on-hold batches. For most practical applications, vacuum decay can test down to 10 microns in a production setting. Detecting a 10 micron defect at time-zero using vacuum decay is significantly more valuable and reliable than testing Oxygen headspace 6 days after packaging, which is a common approach to qualify Modified Atmosphere Packaging (MAP). Vacuum decay is more sensitive and provides immediate, direct quality feedback. In those same 6 days A MAP package is dwelling to perform an Oxygen headspace test, upwards of $1MM in product cost can be packaged and placed on indefinite hold. In cases like these, fast and reliable information provides significant value.

Production operations that require a heightened level of inspection benefit from vacuum decay’s fast, practical, and reliable method. Vacuum decay is robust, simple, and able to withstand even the harshest operating environments. More importantly, it thrives in operator interaction, with its’ simplicity and value added by the quantitative result. All operations benefit from practical technology that operators can rely on and that offers a simple user experience.

Package integrity is often a systematic issue that can benefit from a robust sampling plan. Integrity is the most critical primary package attribute protecting the product during its’ lifecycle. Vacuum decay is a highly effective approach to ensure package integrity, and it offers the fastest return on investment into an organization’s quality. Take control of quality beyond your operation’s walls by deploying the right test method to protect your product quality.