I'm not and have never intended to suggest that I know best - only what my views are. Only that 62353 introduces some confusion RE: equivalent level of safety, i.e. applicable maximum leakage limits, decision when to apply different tests, etc, etc.


Isn't that what the experts on the 62353 panel should be discussing and voting on?


So, if I have read your meaning correctly the leakage, e.g. earth and patient leakage measurements obtained and the limits intended to ensure they are acceptable, are not as important as the methods used to measure them?

One of the biggest points that most seem to miss or not realise the significance of, is the need to compare the test results with previous results.

This is not done in 60601 as all that matters is whether it passes or fails the limit values.

In 62353 you have to look at previous test values to see if there has been a significant change which would indicate a potential failure. In fact many manufactures set limits as to how much a value may change from the initial factory or acceptance test value. As an example a Siemens ultrasound unit is only allowed an increase in any leakage value of 1.5 times the initial value or 10uA whichever is the greater! This would never be picked up in an IEC 60601 test!

Would you want a probe used on your family if it displayed a leakage value of 4500uA? This is a pass for 60601 but would 100% fail a Siemens ultrasound safety tests as the initial value would have been about 4uA!

I understand there are those that don't like change and may see performing fewer tests (as required by 62353) as somehow unsafe but in fact if performed correctly they are in fact much safer that those of 60601 as they will pick up faults that 60601 would miss.

Open your eyes and your mind and embrace the new standard.

I particularly like the Alternative test method as, where it is suitable for use, it works really well and saves lots of time booting up and down PC based devices between tests. Many don't accept the equipment leakage values it reveals but in fact they directly correlate to the 60601 open neutral tests!

I suggest those who dislike the new standard actually obtain a tester that works to 62353 and go back to basics and conduct some tests of their own.

You also need to look at the MHRA DB2006(5) document (which supersedes all others) and note that it says to use an appropriate standard but not 60601. As the only appropriate standard in the UK is BS EN 62353 I suggest al get on board as soon as possible.

Since when does a tech need to be told when to compare suspicious results with those of earlier tests?

And, are you suggesting that techs should apply special care and attention on equipment that may be "used" on members of their family? I hope that users of this forum can rise above nonsense like that!

"Preaching to the converted" is the phrase that comes to mind.

Well although you may diligently compare results you may be shocked and surprised that many do not! I have seen many technicians simply connect a device to test and press the start button on the meter and walk away. As long as they get a tick box at the end then they are happy and move on to the next job. This is probably the way >75% of those conducting an electrical safety test work.

You may be one of the "converted" but many are not and still need some preaching!

Interesting you made no comment on the points about the use of 62353 over 60601? That is my experience on this matter as it seems to descend into a non technical war of words trying to put down anyone who upholds the new standard. Some even feel they can come up with a better standard of their own which can only lead to a worsening of the current situation.

IEC 62353 is not a 'Missed opportunity" if all adopt the standard and interpret it correctly, recognising the points that will increase the safety of testing medical electrical equipment.

After all a common standard can only help in ensuring a consistent approach to safety testing and record keeping.

I am rarely shocked, and never surprised, but I imagine that the "missed opportunity" heading arose from a feeling that IEC-62353 did not go far enough. So called "harmonized" European regulations often end up this way, it seems.

Common standards are nothing new. We have had them since at least the days of HTM-8.

But when any new regulation comes into force, no doubt it will be adopted.

PS: I wonder what next year's version will bring (apart, that is, from the need to purchase yet another tester)?

Well if people have purchased the right tester then I am sure it will be fully upgradable to any minor changes in standards.