The Luer taper is a standardized system of small-scale fluid fittings for making leak-free connections between male-taper fittings and their mating female counterparts on medical and laboratory instruments, including hypodermic syringe tips, catheters and infusion devices.
The two varieties of Luer taper connections are typically known as Luer-lock and Luer-slip. Luer-slip fittings are defined in ISO 594. ISO 594-1 defines the dimensions and validation test specifications of luer-slip fittings. ISO 594-2 defines the dimensions and validation test specifications of Luer-lock fittings. Both sections of ISO 594 define standardized tests which include:
a connection test which ensures that the fitting assembly connects with a specified torque, stays connected, does not leak, and disassembles with a specified torque
an axial force test which ensures that the connection stays together after being properly connected
a torsional stress test which ensures that the Luer fitting does not crack when over-torqued
An additional European standard, similar to ISO 594, is labeled EN 1707. EN 1707 is a European standard with the same title as ISO 594-2, but offers two additional thread alternatives for the female fitting. Luer fitting tests in EN 1707 include tests for leakage under pressure and vacuum, and security of the assembled fitting.
ISO 80369 is a new standard which defines the geometry and dimensions of seven new Luer connections, and their corresponding validation test specifications. ISO 80369 was established to prevent medical accidents involving conflicting treatments which require different Luer connections. Additional testing ensures that Luer fittings cannot be accidentally connected.