ISO 80369-7 Annex C defines six reference connectors for Luer lock and Luer slip testing, numbered C.1 to C.6. They are the controlled counterparts your sample connector is mated against, and picking the wrong one is the most common specification error in Luer testing - not because the parts look different, but because several of them look almost identical and are certified for different test clauses.
The table below is the short version. Three of the six are female reference connectors used to test male samples (C.1, C.3, C.5); three are male reference connectors used to test female samples (C.2, C.4, C.6). Within each group the figures are split by test purpose, not by size.
Which figure do you need
| Figure | Reference connector | Test object | Tests covered |
|---|---|---|---|
| C.1 | Female, Luer lock | Male Luer lock | Leakage, ease of assembly, unscrewing torque, stress cracking, non-interconnectable characteristics |
| C.2 | Male, Luer slip | Female Luer slip | Leakage, ease of assembly, unscrewing torque, stress cracking, non-interconnectable characteristics |
| C.3 | Female, Luer lock | Male Luer lock | Separation from axial load, resistance to overriding |
| C.4 | Male, Luer lock | Female Luer lock | Leakage, ease of assembly, unscrewing torque, stress cracking, non-interconnectable characteristics |
| C.5 | Female, Luer slip | Male Luer slip | Leakage, separation from axial load, stress cracking, non-interconnectable characteristics |
| C.6 | Male, Luer lock | Female Luer lock | Separation from axial load, resistance to overriding |
The three pairs that get confused
C.1 versus C.3. Both are female reference connectors for male Luer lock fittings. C.1 carries the sealing and torque test set; C.3 carries separation force and overriding resistance. A full Clause 6 qualification of a male Luer lock connector needs both.
C.4 versus C.6. Both are male reference connectors for female Luer lock fittings, with the same split: C.4 for sealing and torque, C.6 for pull-and-strip.
C.2 versus C.5. Both involve Luer slip, but they point in opposite directions. C.2 is the male reference connector that tests female slip fittings; C.5 is the female reference connector that tests male slip fittings.
The 10.5 mm and 7.5 mm taper length rule
A minimum taper length of 10.5 mm is required for the non-interconnectable characteristic tests. A minimum of 7.5 mm may be used for the Clause 6 performance tests. This matters in practice: an older ISO 594 reference fitting certified to a 7.5 mm minimum will pass the Clause 6 performance work but will not satisfy a reviewer asking for the non-interconnectable characteristic test. If your notified body or lab asks for that test, the reference connector has to meet the longer dimension.
Common specification and materials
All six connectors are machined from hardened stainless steel at HRC 58-62, with a 0.06:1 cone taper, surface roughness Ra of 0.8 µm or better on critical surfaces, and an edge radius of 0.15 mm to 0.20 mm on lugs and threads. Any radius or chamfer marked R on the drawing is 0.5 mm or less.
What these are not
These are reference connectors, not test apparatus. Pressure, vacuum and axial load come from ISO 80369-20 test equipment, which is a separate purchase. They are also not dimensional gauges: for a simple fit or geometry check on a Luer interface you want a male plug gauge or a female ring gauge. The reference connector exists to be the controlled mating part in a defined test configuration.
The dimensional limits behind all six gauges — Ød, ØD, the Luer lock thread major diameter, the taper length and the 6 % taper angle — are tabulated in millimetres on the Luer dimensions quick reference.
Not sure which figure your protocol calls for? Send us the clause numbers and we will tell you which connectors to order, or quote the six-piece set.
