The ASTM D4332 standard refers to specific conditions of the distribution cycle: how relative humidity and different temperatures can affect the protective ability of the packaging.
Thanks to this standard, it is possible to expose a sample to climatic conditions that mimic those that the package will encounter during transport and storage. In this way, companies can study how the packaging will react and design suitable systems capable of withstanding these conditions.
What is ASTM D4332?
The ASTM D4332 Standard Practice for Conditioning Containers, Packages, or Packaging Components for Testing provides an environmental conditioning-oriented packaging testing method to be used prior to performing transport simulation tests.
For this purpose, ASTM D4332 proposes to subject a sample to climatic conditions representative of the distribution environment. This sample may consist of a container, packaging or various packaging components and materials.
The importance of ASTM D4332: how do climatic conditions affect packaging formats?
Extreme temperature and humidity are key factors to consider when designing a packaging system that works. This is especially true for some packaging materials: For example, for most packaging materials, humidity and temperature are very important factors to be taken into account when deciding the weights of the materials and the specifications to be met by the packaging.
Corrugated board is one of the materials most commonly used by companies to transport and store goods. One of the factors to take into account when choosing the type and grade of corrugated board is humidity. High humidity will affect the internal characteristics of the material and therefore its performance. In the case of paper-based packaging, an increase in relative humidity means that the packaging material accumulates more moisture, which reduces its performance significantly.
Plastic packaging however, is more affected by elevated temperatures, which cause “creep”, the slow deflection of the container while under a higher load. Creep damage can lead to instability on a pallet and cause damage during transport. Therefore, the process proposed by ASTM D4332 to see how these factors influence containers, packaging materials and products includes the following steps:
Choose three conditions to perform the test, taking into account both temperatures and relative humidity. Choose from the following scenarios (although it is also possible to customize these measures, according to needs):
- Cryogenic -55°C ± 3 (RH N/A)
- Intense cold -30°C ± 2 (RH N/A)
- Freezing -18°C ± 2 (RH N/A)
- Refrigeration 5°C ± 2 (85 ± 5% RH)
- Temperature with high humidity 20°C ± 2 (90 ± 5% RH)
- Tropical 40°C ± 2 (90 ± 5% RH)
- Desert 60°C ± 2 (15 ± 5% RH)
- Normal 23°C (50% RH)
- Introduce the sample into the climatic chamber, responsible for generating the chosen atmosphere.
- Perform the test for 72 hours.
- Check the state of the sample and observe if it maintains its properties.
- Generate a report with the results.
Advantages of packaging environmental conditioning test / Ventajas del testeo de condicionamiento climático
Climatic testing protocols such as ASTM D4332 allow companies to know the range of climatic conditions that a packaging system is capable of withstanding. This is especially important in some cases, such as medical packaging or the testing of corrugated box packaging.
Some of the advantages of conducting this type of testing include:
- Validate the packaging design or improve it: simulations allow to detect problems in the product and/or packaging design before launching it on the market. In this way, companies are able to optimize their design and validate it to ensure that it will withstand the conditions of the distribution cycle.
- Environmental stress tests help predict package or product shelf life.
- Eliminate costs resulting from inadequate protection of the transported product. If the product arrives in poor condition because it has not withstood the environmental conditions during transport, companies face costs due to shrinkage, claims or product returns.
- Ensure that the packaging is secure and will remain intact during transportation, handling and storage.
You might be interested in: ‘Guidelines for maintaining cargo stability during transportation’
Additional standards to ASTM D4332 for atmospheric conditioning / Otros estándares para el condicionamiento atmosférico
The international standard ISO 2233 specifies a conditioning and climatic testing method for full and filled packages and unit loads. To carry it out, temperature and relative humidity conditions must be chosen and the sample must be subjected to them for a period of 4 hours to 4 weeks, depending on requirements.
Depending on this standard, pre-drying of the sample may be necessary (e.g. for materials such as chipboard).
All this information should be collected in a final report, including the effects of environmental conditioning on the sample studied.
The ASTM F2825 Standard Practice for Climatic Stressing of Packaging Systems for Single Parcel Delivery covers the method for evaluating the ability of packaging to maintain its protective capability against temperature extremes.
However, this method does not include cryogenic temperatures, refrigeration or freezing conditions: only those climatic conditions understood as normal (daily averages) in various climates.
The ASTM E171 Standard Practice for Conditioning and Testing Flexible Barrier Packaging defines a method for conditioning plastic and paper samples against temperatures and humidities typical of the distribution cycle.
>ISTA series that include atmospheric conditioning
Two of the ISTA series testing standards include climatic testing methods (pre-conditioning and atmospheric conditioning based on ASTM 4332 and ISO 2233) among their test sequences:
- ISTA 2: includes methods for atmospheric conditioning, in addition to compression testing, fixed displacement or random vibrations and impact testing.
- ISTA 3: this general simulation protocol for unit loads or packaged goods is oriented to the transport of individual packages in shipping services such as UPS, DHL or FedEx, among others. This series includes, in addition to atmospheric conditioning and preconditioning methods, vibration and impact tests.
Want to know more about the ASTM 4332 testing method and the importance of environmental conditioning in the context of packaging testing? At Safe Load Testing Technologies we help companies achieve safe packaging through our testing equipment and our more than two decades of experience in the transportation simulation industry. Contact us and let’s talk about how we can help you.