ISO 7886-1 Testing Sterile Hypodermic Syringes
Hypodermic syringes are critical medical devices that allow medication to be delivered safely and efficiently at very precise doses. Because of their importance, it is crucial that hypodermic syringes perform as expected at all times. A leaking syringe can result in improper medication dosing and wastage and cause procedures to be delayed. The force required to expel liquid from the syringe must also be small enough to ensure that any medical professional can perform the task without resistance.ISO 7886-1 Annexes and Measurements
- ISO 7886-1
The ISO 7886-1 standard regulates the mechanical properties of hypodermic syringes and outlines the specifications for single use hypodermic syringes. It also includes information related to the design, manufacture, and functionality of the devices, while the annexes of the standard describe the standard operating procedure for testing these devices. Whereas ISO 7886-1:1993 discusses mechanical testing in annex G, the newer version of the standard, ISO 7886-1:2017 discusses it in annexes D and E.
Annex D measures the quality of the plunger stopper seal by simultaneously applying a perpendicular force to the syringe barrel and maintaining a constant compressive force on the syringe piston. A visual check is performed to ensure that no liquid escapes past the plunger stopper seal. This annex is less commonly tested than Annex E, which measures the forces needed to operate the syringe plunger with water in the barrel. The force profile typically displays an initial peak force known as the break loose force, and an average force of the remaining plunger travel, known as the glide force. This test also requires the recording of maximum force during plunger travel excluding the break loose force.
ISO 7886-1 testing is performed on a single column universal testing system such as those found in Instron's 3400 or 6800 Series. A 2870-003 syringe fixture is required and is designed for this method specifically. Because the forces involved are relatively small, a 100 N or 50 N load cell is preferred. A biotray may also be helpful since there is potential for spillage from the reservoir onto the test system frame.
|ISO 7886-1 Test Setup|
|1)||3300 Series Universal Testing System
|2)||2530 Series Load Cell
|3)||2870-003 Syringe Test Fixture|
ISO 7886-1:2017 introduced many changes which require altering the test procedure and the results. The previous version of the standard required the expulsion and aspiration of the syringe while the newest version only requires expulsion similar to a typical break loose and glide force test. The fixturing has also changed, with the old method requiring the tubing from the syringe to be affixed to the reservoir. The new version requires a specific gauge and length needle to be attached to the end of the tube and then placed in the reservoir, resulting more repeatable results. To review the requirements in full, read the standard. To learn more about drug delivery device and container testing, click here.