Talk:Poka-yoke/Archives/2013

Some other examples of Real-World Poka-Yokes

I believe many of these examples are poor: some may technically be poka-yoke but do not make a nice distinction between that and simple fail-safe mechanisms. The overflow drain on a sink is a severe example, as there is nothing poka-yoke about that...it's a simple fail-safe. -> A much better (also automotive) example would be the sizing of gasoline nozzles. Unleaded is small, leaded is larger. This means you cannot put leaded gasoline in an "unleaded car" (which damages the catalytic converter) because the nozzle is larger than the filler neck opening. However you can put unleaded in a leaded car (which has no adverse effect). -> On a related note, a nice counter-poka-yoke example is that the diesel nozzle is larger still. While this does mean that you can't put diesel fuel in either a leaded or unleaded car, it does not prevent you from filling a diesel car with gasoline, which depending on the mixture of residual diesel, will make the diesel run poorly, not run at all, or cause damage. — Preceding unsigned comment added by 12.230.177.190 (talk) 20:25, 1 October 2012 (UTC)

The term fail-safe is not the same as goof-proofing as a fail-safe mechanism CAN fail. But when it does it fails so as to do no harm (ie; “safe”). It is not preventing the error, just the damage caused by the error. Goof-proofing (poka yoke) is preventive. A good combination would be a poka-yoke that prevents (mostly) an incorrect assembly, and a fail safe design that, even if the assembly is done wrong, the resulting failure causes no damage (it simply won't work, fails to start, etc). A poka-yoke without a fail-safe design is one where the chance of an incorrect assembly may be reduced but if one slips thru, the circuit gets fried in test. or something like that. The distinctions are a bit murky, and this is simply how I separate them. In the end, what we call it doesn't matter nearly as much as getting it done.Ken (talk) 22:08, 8 November 2013 (UTC)

I have changed the opening paragraph to an example that more people are familiar with (car starting interlocks), and deleted the reference to SIM cards. Ken (talk) 20:44, 13 March 2013 (UTC)