Sorry there's been a confusion here. The "green dot" idea was to ensure that the same earth test point is used on Class I equipment to ensure that the same point is used each time when testing earth bonding to check that there hasn't been any degradation of earth continuity when you do an annual electrical safety test as part of a PPM process when earth bond impedance is recorded. Where do you put your safety tester's earth clip for a Class I all insulated item which only has an equal potential earth pin accessable which connects to the internal earthed metal chassis? (e.g. an HP defibrillator)
As I said, a lot of medical laboratory equipment does not have an external idendified earth connection, hence the green dot to identify which point you are connecting your earth clip each time you carry out the earth bond test on the equipment. I would of cause suggest that the earth clip is moved to another part of the earthed chassis for earth leakage current tests, incuding patient leakage.
I agree with Richard that the problem of using automated electrical safety analysers (or testers)is understanding exactly what is being tested and it's important to always carry out a very full visual inspection when testing equipment.
There are real practical problems of the amount of time that one can spend on electrical safety testing in a busy hospital Medical Equipment Management unit when the hospital has over 2000 items of equipment. I suppose to do this properly one would have to employ someone full time on this task, which is just not possible in our MEMU
