If you want to ensure your package is performing at its optimal level, it is likely that you are already conducting leak testing. However, simply leak testing is not enough—you should also know your package’s failure point, and understand what this means for its performance. 

Often, leak testing is completed to a set level in order to determine that a package can withstand specific conditions, rather than to failure. While testing packages to a level that only ensures it will not lose integrity over its regular lifespan is important, you are in fact missing out on opportunities for early detection of deterioration, as well as potential package improvements. Today, we will discuss why it is important to test package to failure by using Burst Testing, and why this is a critical step in leak testing procedures. 

What is Burst Testing?

Burst testing, also called “seal-failure testing” is a method that stresses a package to the point of failure—until it bursts or springs a leak. Packages are exposed to increasing lower Vacuum Atmospheres increasing the pressure differential between the package atmosphere and the surrounding environment . When the stress undergone by the package becomes too much, the package will burst or spring a leak, revealing their point of failure or weakest point. 

Burst testing provides manufacturers with an indication of the ability of their packaging to withstand internal pressure, the maximum pressure required to cause package seal failure, as well as information on overall package reliability. A package’s point of failure may indicate how a package will perform not only during manufacture, but also throughout its distribution and storage. 

Burst testing is a popular package testing method due to its effectiveness. It is used in a variety of industries, including those that need to be able to maintain and measure the strength of a Sterile Barrier System (SBS), such as the medical and pharmaceutical industries.

Why Use a Burst Test?

While there are many types of package quality tests available, burst testing allows you to effectively assess the safety and quality of your packaging. The main objective of a burst test is to determine the ultimate failure point of the packaging, allowing you to understand the package’s safety factor as well as where and how the package will burst. Ultimately, this will allow you to evaluate the package’s design as well as its suitability for your product. 

Burst testing does not only evaluate your package’s performance at the time of manufacture. Putting your package  in Vacuum atmospheres until they  reach their failure point allows you to simulate potential shipping conditions, ensuring that it will maintain its integrity when being shipped at high or changing altitudes. FlexPak Package Leak Detectors perform ASTM D6653 Testing Standard, allowing you to effectively simulate altitude and evaluate package performance.  

Why Trending Failure Points is Important

When completing burst testing, it is important to test your packages to a point where they will continuously fail. Trending a package’s failure point will allow you to understand your packaging, its strength, and its overall integrity… and identify when its performance is weakening. 

If the package seals or substrate are weakening, it will be easily identified as the package failure occurs at a lower Vacuum Setpoint. By identifying the package seal integrity is weakening, you will be able to take pre-emptive measures to avoid critical failure and major loss of product. This early identification will save product costs, down-time, and last minute package changes. 

In order to properly trend your package’s failure point, you should conduct continuous, regular testing. Depending on your individual needs, you may choose to test products taken off the line at random intervals, or to implement testing at set intervals—one package test for every hundred finished products, for example.

You may have set an acceptable testing level for your packaging at 40 kPa in order for your package to withstand regular external conditions over its lifetime. However, in testing to failure you may realize that your package can withstand up to 80 kPa. This is its failure point. By trending this failure point and conducting regular burst testing, you will be able to detect if your package is beginning to weaken. 

If you notice that the failure point move to 60 kPa, you will know that something has gone wrong, allowing you to investigate and correct the issue before it results in product loss. Without this method of testing, your package would have continued to test to its acceptable level— and the package deterioration would not have been detected. 

Using a VAC Attachment to Increase Pressure

In some instances, you may need to increase the stresses on your package seals further than is possible using the standard FlexPak Leak Detector to reach its failure point. Using a VAC attachment will allow excess air to enter and expand your package, applying additional forces to the seals. This additional pressure will allow you to conduct burst testing, determine a failure point for your package, and begin to monitor your packaging properly. 

Testing to a package’s failure point is an important step in any leak testing procedure, and is a reliable way to determine if package quality is deteriorating. Ensure your package is able to withstand internal pressures and consistently reach your customers undamaged by trending your package failure point. 

FlexPak Test Methods 

FlexPak Package Leak Detectors provide several seal integrity testing solutions to suit your needs. FlexPak’s diverse seal integrity tests can ensure your packages meet the required ASTM testing standards in your industry, with the ability to test a variety of product and packaging types.  

Bubble Leak Testing: Bubble Leak Testing is completed in an acrylic vacuum chamber.  The sealed product is submerged in water and, when put under Vacuum, bubbles will form at any compromised points in the packaging.  Bubble Leak Testing is an easy visual test that will ensure your packaging’s integrity while adhering to the ASTM D3078 testing standard.

Detecting Gross Leaks In Packaging By Internal Pressurization: The ASTM F2096 Testing Standardprovides highly accurate testing for pharmaceutical and medical packaging, allowing users to detect leaks, substrate holes, and channels accurately and reliably.  The sensitive nature of this test means it can detect leaks that a standard Bubble Leak test cannot, and it can also be used with a variety of package shapes and sizes. 

Altitude Simulation Testing: Altitude Simulation testing, the ASTM D6653 testing standard, is a package integrity testing method that simulates the extreme pressure changes a package may undergo during transport. An altitude test will simulate ascent and descent rates, as well as a set altitude for an extended period of time, ensuring that the packaging can withstand its transport and reach consumers intact.  

Dry Chamber Tests: A Dry Chamber Test is performed without liquid in a leak detector tank.  This procedure is best suited for packages containing liquids, such as condiment sachets or bottles with lug-style and threaded caps.  The package is placed within the chamber on an absorbent material and, when  exposed to Vacuum the higher internal pressure of the package will push against the package seals. Any leaks will result in the presence of liquid within the dry tank. The ASTM D5094 testing standard is performed in a dry tank environment. 

From Fruit to Pharmaceuticals, Meat to Medicine, and anywhere in between, FlexPak is the most reliable solution when it comes to package seal integrity and leak testing equipment.  Contact us now at (416) 399-5583 or visit us at https://flexpakinc.com for more information or to request a quote.