ASTM D4168 Shock of Foam-In-Place Package Integrity Testing

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Summary of ASTM D4168 Shock Testing

ASTM D4168 package testing consists of using the cushioning material to be tested to support a weighted test block inside a package. Either Test Method A or B may be used. However, the two methods will not necessarily give the same result.

The values stated in inch-pound units are to be regarded as standard. These values are mathematical conversions to SI units that are provided for information only and are not considered standard.

Data obtained by these methods may be used to determine the transmitted shock characteristics of foam-in-place packaging materials. This data allows designs of cushioning systems that can provide adequate and efficient use of foam for the protection of goods during a distribution life-cycle.

Significance of ASTM D4168 Cushion Testing

Cushioning materials can vary in performance, which leads to different levels of test variability. In general, the ASTM D4168 procedure avoids bias because results are defined strictly by the test method. However, materials that undergo severe deformation under higher loads or drop heights often show increased variability in results.

The shock integrity report documents the full testing process in detail. It includes the test procedure used, machine specifications, and the orientation of the package during testing. In addition, it records the number of units tested along with any observed failures.

Specifically, the ASTM D4168 report may also include a description of the cushioning material, conditioning parameters, and drop height (in inches). Furthermore, it provides a detailed account of any deviations from the standard procedure.

ASTM D4168 Pre-Molded Cushion Shock Testing Procedures

ASTM D4168 evaluates foam-in-place cushioning materials in the same configuration used in actual packaging. In particular, the method tests the combined system of plastic film, foam, and the shipping container. As a result, it provides a realistic assessment of package performance under shock conditions.

The standard includes two test methods. Test Method A uses a free-fall drop test apparatus, while Test Method B uses a shock-testing system. Each method evaluates how well the cushioning system protects the product during impact events.

Conditioning

First, the test unit is conditioned to reach equilibrium before testing. Standard conditioning is performed at 23°C and 50% relative humidity. This step helps stabilize the materials and ensures consistent test conditions.

Shock Testing

Next, the test block is adjusted to achieve the required static load. Then, five drops are performed under the selected test conditions. Throughout testing, the box is oriented so the weight remains on the cushioning material for each impact. A single sample is typically limited to a maximum of five drops.

Test Method A: Free-Fall Drop

To begin, the release mechanism is set to the required drop height. The specimen is then placed on the support system. After that, the machine is operated according to the manufacturer’s instructions. This process is repeated until five drops are completed at the specified conditions.

Test Method B: Shock

For this method, the specimen is securely attached to the shock test carriage. The input accelerometer is mounted as close as possible to the outer container. The machine is then operated to generate the required acceleration-versus-time pulse. During testing, the accelerometer output is monitored to confirm proper pulse generation. Finally, the test is repeated for a total of five drops under the selected conditions.

Test Report

Following the testing, a test report is created encompassing the following information:

• Name of manufacturer
• Drop height
• Conditioning parameters
• Number of specimens tested and date of test
• Bottom cushion preparation method
• Test apparatus and procedure used
• Detailed description of any deviations from the procedure

Expert Transmitted Shock Package Laboratory Testing

Keystone has a full lab of test equipment which permits us to provide short lead times on scheduling. Our team strives to give our customers more time and energy on product development instead of testing. Keystone Package Testing can accommodate flexible and rigid packages of all sizes, including large pallets.

Ready to get started? We are. Request a quote and see why so many customers trust Keystone Package Testing with their ASTM package testing.

For more referenced ASTM standards and similar testing, please follow the links below:

• ASTM D996 Terminology of Packaging and Distribution Environments
• ASTM D3332 Test Methods for Mechanical-Shock Fragility of Products, Using Shock Machines
• ASTM D5276 Test Method for Drop Test of Loaded Containers by Free Fall
• ASTM D5487 Test Method for Simulated Drop of Loaded Containers by Shock Machines

Interested in the EMC/EMI, climatic, dynamic, shielding effectiveness, or IP Code testing of a product? Follow the corresponding links or www.keystonecompliance.com for more information.