What are Luers
Luer is named after a German medical instrument maker called Hermann Wulfing Luer, who patented a glass syringe. Later, dealers created the Luer fittings to prohibit needles slip off. Luer fitting is developed into small tapered connections as a leak-proof solution for any two parts connected to medical instruments.
There are two main types of Luer: male Luer and female Luer. The male Luer lock has internal threads, while the female Luer Lock has the external lines at the base of the taper. The male Luer and female Luer join to create a secure but detachable leak-proof connection.
That’s why Wikipedia defines it as “a standardized system of small-scale fluid fittings used for making leak-free connections between a male-taper fitting and its female mating part on medical and laboratory instruments, including hypodermic syringe tips and needles or stopcocks and needles.”
Why standard Luer fitting
With features easy-to-use and good leakproof, Luer started to be widely used on many medical systems like vascular, enteral and respiratory, etc., through various tubes, catheters, and syringes. The compatibility of Luer between different medical systems links to the risk of accidental misconnections for clinicians. Misconnection causes severe injury and death. To improve patient safety, ISO80369-7 develops and governs the standards for Luer fitting. It standards both dimensions, tolerance, and testing procedures to minimize the risk of misconnection.
What differences between Luer lock and Luer slip
Syringes are one of the most common instruments using the Luer fitting system with the male Luer connection fitting the female needle, which either screws into it or fits tightly on top. These can be split into two varieties by the connection type: locking or slipping. (The laboratory People, CAMLAB).
As seen below image, we can see that the Luer lock has an internal thread with a slip at the center, while the Luer slip syringe has no lines, only a slip.
The Luer Lock is more secure because the needles need to be rotated and twisted into the syringe, ensuring no liquids leak and preventing accidental removal of hands.
The connection relies on slipped friction while the Luer Slip is pushed into the needle. As a result, it’s not as firm as Luer lock by threads but easier for fitting.