The standard ISO 7886-1 : 1993 Annex D specifies a test method for liquid leakage at syringe piston under compression. The procedure includes the following steps: 1. Draw into the syringe a volume of water exceeding the nominal capacity of the syringe. 2. Expel air and adjust the volume of water in the syringe to the nominal capacity. 3. Seal the syringe nozzle using the cap provided. 4. Apply and axial force and maintain it for 30 seconds. 5. Examine the syringe for leakage of water past the piston seals.
For this particular test, a force value 20% below the level when a failure of the cap was registered was the force selected to constantly apply during 30 seconds. This period started after the selected force level was reached for the first time. After this test, a leakage at the nozzle cap should be visually detected, a leakage either partial or total can be also monitored if a drop in the force level is noticed during the test. The Instron Syringe fixture CP102517 provides an ideal solution for a liquid leakage test, the Instron® software Bluehill® also provides the required control tools to easily perform a force hold during this test.