Cold Chain Package Testing

Cold Chain package testing is used to test the ability of the package system to protect temperature-sensitive products as they move through the supply chain. Cold Chain package testing can help ensure that perishable items such as food, pharmaceuticals, and medical products remain within the desired temperature range during transportation.


Most people probably don’t think about the Cold Chain much and even less about Cold Chain package testing. Cold Chain refers to getting products like fruit, meat, pharmaceuticals, and ice cream through a low-temperature controlled network from the point of manufacture to the consumer and requires either refrigerated or frozen conditions.

The Cold Chain can be divided into active and passive systems. Active systems control conditions most since they use a refrigeration system. Think of a refrigerated trailer filled with produce using an external refrigeration system that requires fuel. There are also battery-operated refrigeration systems that do not require a separate fuel supply during transportation.

Passive Cold Chain packaging consists of gel packs or dry ice as common refrigerants and uses an insulated shipper, like an expanded polystyrene cooler. As one example, the pandemic launched a new focus on Cold Chain packaging as companies providing meal kit subscriptions blossomed. As a result, these Cold Chain package systems had to be tested to ensure the product’s efficacy and safety.

What Is Cold Chain Testing?

There are two distinct parts to Cold Chain package testing. Thermal performance qualification evaluates the ability of the package system to maintain the required temperature conditions. Just as important is testing the package through a simulated distribution test. The results of both tests are vastly different and provide a full picture of what to expect from the Cold Chain package system.

Thermal performance qualification evaluates the effectiveness of a thermal package to provide the necessary conditions over a defined period. The core design of a Cold Chain package system consists of insulation and a refrigerant. The combination of these two components will determine the package system’s effectiveness. Certain products, such as food, chemicals, and pharmaceuticals, must be kept at specific temperatures as they journey from the manufacturer to the consumer. Refrigerated conditions are typically +2°C to +8°C (+35.6°F to +46.4°F) and can often be challenging to maintain. Frozen conditions, 0°C (+32°F) and below, are typically easier to maintain. Thermal performance qualification quantifies the ability of the Cold Chain package design to maintain the required temperature range.

Once the Cold Chain package has passed the thermal performance qualification, the next step is the distribution test, which may utilize ISTA 3A, ASTM D4169, or another protocol to include distribution hazards such as impacts, compression, and vehicle vibration. Upon test completion, the Cold Chain package is opened and evaluated to examine the condition of its contents.

Importance Of Cold Chain Testing

When it comes to transporting temperature-sensitive products, there’s not much room for error. Any excursion outside the required temperature range can damage or destroy the product. For example, a food shipment can quickly spoil without the proper protection. Likewise, pharmaceuticals that haven’t been kept at the appropriate temperature can pose a severe health risk to patients.

Common carriers like FedEx and UPS have invested heavily in the equipment and infrastructure necessary to transport temperature-sensitive products worldwide. Yet, even with all this infrastructure, successful delivery starts with the package. Therefore, the manufacturer needs to qualify the Cold Chain package system, whether the product is a pallet load of cut flowers or a single shipper containing vaccines, to ensure the design meets requirements. Westpak has the tools and expertise needed to thoroughly assess the thermal and physical characteristics of all Cold Chain packaging.

Frequently Asked Questions

Get answers to our most frequently asked questions.

What's involved with cold chain package testing?

In most cases, a Cold Chain package is a passive system requiring an insulated material and refrigerant in the form of a gel "brick" or dry ice. The person conducting the test must consider several variables before performing a test on a passive Cold Chain package system: one of the most critical is the thermal mass of the product. Thermal mass is defined as the ability of a material to absorb, store and release heat. For example, there is a big difference in the thermal mass of containers of ice cream and medicine vials. The most significant components of a Cold Chain package are primarily the shipper, typically a premade insulation layer providing thermal resistance, and the refrigerant, usually gel packs of water or saline, or dry ice. Therefore, defining the requirements before conducting any cold chain testing is essential. The following is a list of other variables to be considered.

  • Required product temperature range
  • Thermal mass of product
  • Shipper thickness or density
  • Amount of refrigerant
  • Duration in transit
  • Temperature profile to be used for qualification
Once the above variables are defined, the next step is to develop acceptance criteria for the Cold Chain package. The acceptance criteria are how you will know whether the package meets your requirements. Acceptance criteria can be as simple as “The package must maintain a temperature range of XX degrees for a duration of XX hours.” Now qualification of the Cold Chain package can begin and involves:

  • Instrumenting the product with thermocouples
  • Assembling the package
  • Subjecting the package to a temperature profile
However, there needs to be agreement about what temperature profile to use. A temperature profile that is too mild or too extreme can make or break a Cold Chain package. Using a temperature profile based on actual data defined in published standards is the most effective way to qualify Cold Chain packaging.

What is the temperature of the “cold chain”?

The appropriate temperature for cold chain transportation will depend on the type of product being transported. Typically, these fall into two categories: refrigerated and frozen. Refrigerated is defined as +2°C to +8°C (+35.6°F to +46.4°F), and it is often difficult to stay within this range. Knowing the temperature range of the product can help in the successful delivery and function of the product. The acceptable temperature limits of the product may be higher than +8°C and can be used in defining the acceptance criteria for the qualification. Frozen conditions usually do not vary since dry ice is typically used to meet these requirements. Dry ice sublimes (turns from a solid to gas) at -78.5°C (-109.3°F) was ideal for transporting COVID vaccines.

What types of products benefit from cold chain testing?

Any temperature-sensitive product must be maintained within a specific temperature range. Therefore, knowing whether the package holds the necessary condition is essential. Cold Chain package testing is conducted to confirm that the product temperature can be maintained throughout the distribution cycle. Also, having Cold Chain package performance data available is valuable when dispositioning products should a shipment get delayed during distribution.

Why is it important to maintain a cold chain system?

Cold Chain packaging is just one part of the Cold Chain system. Today, the distribution environment may include Third Party Logistics (3PL) companies with tracking systems and the ability to “refresh” a package if necessary. Having these services available ensures the success of the Cold Chain package in the event of an unforeseen delay. These support systems have become more critical due to the current interruptions in the supply chain.

Which test standards are associated with cold chain package testing?

The following test standards are associated with Cold Chain package testing and include both package qualification and distribution testing.

The team at Westpak is experienced and capable of conducting Cold Chain testing and interpreting the results. Contact us today to learn more about how we can help you facilitate a successful shipping operation.


Testing at Westpak has been accredited by A2LA to comply with ISO 17025.

Westpak testing labs are ISTA certified to perform a variety of tests.


If you have any questions or are not sure where to start, our Westpak experts are here to help!

Ask an Expert

Would you like us to send you a quote?

Request Free Quote