ASTM D7860 Torque Retention for Child Resistant Packaging
Standard Test Measurements using Automated Torque Testing Equipment
ASTM D7860 is a testing standard that focuses on characterizing the torques associated with thread-based closure devices of medical packaging. This standard is most commonly used for pharmaceutical pill bottles. This test ensures that all consumers - regardless of hand strength - can easily remove bottle lids to access their medication. This test also ensures that the child-closure mechanism is working properly, a critical check for the safety of young children.
For ASTM D7860 testing we recommend an Instron 6800 Series single column system with Torsion Add-On 3.0. for the lower grip, four post torsion grips are ideal since they can accommodate a wide range of bottle geometries. The upper grip should be a lathe chuck capable of grabbing onto the cap. The load cell should be biaxial.
| ASTM D7860 Test Setup | |
|---|---|
| 1) | 5900 Series Universal Testing System |
| 2) | Bluehill Universal Software |
| 3) | 2725-302 Biaxial Load Cell |
ASTM D7860 requires the test machine to apply the closure torque recommended by the manufacturer, and then determine the torque needed to open the packaging. Child-resistant closures require an additional evaluation of the force needed to align and subsequently engage the threads. The opening torque is captured at various time frames after the initial closure – this is defined by the standard and ranges from minutes to days. The purpose of this is to evaluate the torque retention, a measure of the difference in removal torque immediately after closure and for up to four weeks afterwards.