Luer

Luer is a standardized system of small, conical fittings used to connect syringes, needles, catheters, and other medical or laboratory devices. The name comes from Johann Friedrich August Luer, a German instrument maker who described the conical taper in the late 19th century. The Luer taper provides a secure, low-dead-volume connection intended to be interchangeable among compatible components.

Luer fittings are commonly categorized as Luer slip, which forms a friction-fit without a locking mechanism, and Luer lock, which uses a male-threaded collar to lock the connection in place. There are also variations such as compact or mini variants, but the essential concept is a standardized conical interface that mates with a complementary part. The system is designed to be simple to use while maintaining sterility and quick interchangeability in clinical and laboratory workflows.

Standards are defined by international documents such as ISO 594-1 and ISO 594-2, which specify dimensions and tolerances for Luer taper fittings to ensure compatibility across manufacturers. In practice, the system is widely used in medicine and laboratory work, including syringes, needles, IV administration sets, dental devices, and reagent- or sample-transfer components. Variants and adapters allow connections between Luer fittings and other types of connectors.

Materials for Luer fittings commonly include medical-grade plastics such as polypropylene or polycarbonate, as well as stainless steel for certain connectors. The fittings are typically disposable in many settings to maintain sterility and reduce cross-contamination.

Safety considerations include the risk of misconnection to incompatible medical systems, particularly when different devices use similar fittings. Luer lock variants help mitigate accidental disengagement, but proper device selection, training, and adherence to standards remain essential.