EBME Forums Forums Free discussion Free discussion IEC 62353 - MISSED OPPORTUNITY?

I have recently attended an informative presentation regarding the recent IEC 62353
recommendations/standards applied to the electrical testing of medical equipment in service as opposed to the IEC 60601-1 type testing standards.

I was impressed with the conclusions and thought it a step forward in standardizing the important issue of electrical safety testing of medical equipment. Unfortunately it is quite meaningless, like most UK standards of electrical testing, since no one HAS to comply with them unlike the standards in many enlightened countries such as Germany or Australia. In practice many Doctors’ Surgeries and Health Centres use IEE type electrical PAT testing of their medical equipment, I would be interested to know the patient leakage currents they measure. Their ignorance of the difference in standards between electricians Portable Appliance Test and the standards regarding testing of Medical Equipment is also shared by the electrical contracting PAT testers; but as they are usually paid per item why should they worry?

On the subject of electrical testing my hospital’s management clearly encourages the electrical testing of medical equipment but does not apply any importance to the testing of the individual IEC leads, this I find very strange.

I suppose I am one of the ‘old boys’ that can remember when Britain was indeed Great and was not afraid to uphold ‘standards’ in which they believed. Although I am vehemently opposed to unwarranted regulations I believe this was an opportunity missed in not making it mandatory for all medical equipment to undergo regular testing to reduce dangers to users and patients.

What are other members thought?

Regards

Barney

I reckon you need to spend an evening trawling through earlier threads that have touched on this topic, Barney. They are myriad!

Employers have a "duty of care" and can be prosecuted if they fail to exercise it. It's all down to the H&SAW Act (off the top of my head), or something like that. Some sort of legislation, anyway.

If electrical safety testing of medical equipment was made mandatory as you suggest, the first thing that would happen is that engineering managers would be howling for the extra resources that this would entail!

Enjoy your homework, Mate. We all look forward to your summary sometime tomorrow (or the day after). Ha, ha.

Believe me Geoff, the work is already being done by electricians doing PAT tests on Defibs/ECG machines etc at Surgeries, and we as tax payers are paying for a test that was only intended for fridges,vacuum cleaners and kettles not for patient connected medical equipment.

Barney

Yes, I've seen it for myself, Mate (many times). I was at a vet's doing some servicing on ultrasound kit a couple of months back, and enquired why the staff there allowed grubby local sparkies to put their stickers (and, supposedly, carry out their test) on "my" nice equipment. All I got was shrugs, and mumbles about how the two young chaps just came in and "checked everything". I think I frightened them a bit when I mentioned the word "warranty" in relation to our (expensive) kit (well, it belongs to them really, but I expect you know what I mean).

By the way, they apparently always go around in pairs. Plus and minus, I suppose.

To make testing mandatory under legislation, i.e. meaningful in law, a period between tests would have to be specified, explicitly (as well as the use of a testing standard, e.g. 62353), for devices based on the risk presented by devices, their likelihood of failure and the environment that they're used in.

In any case, given the diversity of devices and the risks presented, if testing were not performed at "regular intervals" that're considered acceptable under law, enforcing "reasonable testing intervals based upon risk" for a particular devices would be difficult. The problem is that individuals' idea of reasonable test interval varies in practice - usually heavily influenced by the resources that're available for testing.

To make the requirements of legislation easier to implement hence enforce, perhaps, there would have to be a mandatory test on all devices at an interval that's fixed and, ultimately for many devices and applications, the interval between testing would not be realistic given the number of devices in a typical general hospital and the complexity of tests associated with a significant proportion of the high-risk devices.

Visual inspection, basic functional checks and electrical safety checks would be necessary whatever the medical application or electrical device involved. The basic testing methods indicated in 62353 are, in fact, almost identical to those indicated in 60601-1 under normal conditions except that IR tests are now specified, explicitly, lower earth bond currents appear to be encouraged, plus there are some other relatively minor changes in allowable earth-bond figures, etc.
The tests now formally specified in 62353 but not 60601-1 consist of stuff that most individuals have considered good practice for years when performing 60601-1 tests, anyway; most of which have already been included in many electrical safety testing products already on the market.

One thing that 62353 is very useful for, even if its use is not mandatory, is that manufacturers and service agents can use it as a benchmark for stating, more explicitly than 60601-1 does, good practice in routine safety testing in much the same way as manufacturing standards are used by manufacturers to illustrate to notified bodies/competent authorities, etc, that good or "state of the art" engineering/design practices, essential safety aspects and performance considerations are being applied.

Therefore they have a good argument when specifying the requirements of servicing/testing, including safety testing which was previously out of their "control" and the domain of EBME/Medical Physics, etc, based upon selection of tests that were not previously specified in writing - hence somewhat open to interpretation.

I must admit that I do have concerns that it is possible that tests indicated in 62353 could "pass" medical devices with a single fault condition present (that have actually been designed under 60601-1 to protect the patient under a single fault condition) and that some leakage limits (especially compared to those in the in the 3rd edition 60601-1) may not be fully compatible with 60601-1.

Potentially, over the life of the device or system, lowering the "safety margin" designed into new products that're manufactured by companies adhering to the essential safety requirements of 60601-1. However, saying this, I've not had an opportunity to fully study the "ins and outs" of both the standards and compare them properly, yet, plus failures are few and far between so the risk of a scenario where 62353 misses an SFC in a medical device and a second fault occurs is probably very low thus an acceptable one.

Perhaps anyone who disagrees would care to comment?

Thanks Barney for your kind comments on our seminar. I am pleased you found the information useful.

It was very interesting for me to receive many positive comments on the IEC 62353 yet the UK experts voted against the IEC 62353 draft.

Geoff is right about the legal requirements only being driven by the HSE. How can you prove something is save if you do not test. I therefore believe more guidance would be beneficial on testing intervals (shortfall on the IEC 62353)

However, as mentioned in the seminar, the IEC 62353 is published and will further develop over the years (just like the IEC 601 has done over 30 years) to grow to a better document perhaps suitable for making it mandatory (it will be mandatory in Germany next year). This would make matters clear and will get rid of the pat testing "biomed" engineers like you have mentioned in this forum.

As is clear from this forum, the IEC 62353 will provide a more efficient and saver working practice across the UK for those who currently test to IEC 60601 (or pick and mix – see previous forums)

For those who missed the seminars or would like to receive a copy of the presentation, drop me an email (johnb@seaward.co.uk)
We aim to continue with further seminars in the near future. Any suggestions on locations across UK and Ireland or even abroad?

Thanks

John Backes.

A couple of comments come to mind. Why so many standards? IEC-this, and IEC-that. It's all very confusing (except, perhaps, to those making a career out of it all). Why can there not be just the one regulation for routine "PAT" testing of all equipment, with medical equipment in sub-set?

And why are we always in such a state of flux? After all, would you say that the kit itself (ie, the medical equipment to be tested) has changed fundamentally in the last ten (twenty, thirty) years? Why can't we just fix a set of criteria and then get on with it? Bring back HTM-8!

Excuse me, but I thought that the United Kingdom was already part of the European Union. So, if it's to be mandatory in Germany ...? What's the score here (more bloody chaos, by the sound of it)?

I wonder if anyone from the IEC lurks on this forum? I hope so.

Suggestions on locations, John? How about Cloud Cuckoo Land?

Thanks for all your comments.

I attended John’s seminar at Bristol and can highly recommend it to all Biomeds.

Regarding it being mandatory to test, surely it is better to test medical equipment to a medical equipment standard than to allow the electricians PAT test to replace it, which is what is happening outside the hospital environment.

As Richard correctly states the PAT test intervals are also not mandatory the IEE set out a code of practice with recommended intervals, however in the real world this means small businesses calling in the local electricians and they will PAT test everything in sight at a yearly interval. This is of course better than not testing but surely a label on a ECG machine saying it has passed its electrical safety test is misleading if the item has not been tested to a ‘medical equipment’ electrical standard test such as the IEC 62353.

I do not accept the view that it would be difficult to cope with mandatory intervals since I consider that many items could be tested at wider intervals than many hospitals attempt to meet at present. At least having an interval based on evidence of failure and practical achievement would ensure that all medical devises would be tested to a medical electrical standard.

Incidentally having been as Geoff colourfully describes, a ‘grubby PAT tester’ in previous employment, I maintain the most important test of all is the visual inspection and testing of the mains lead, especially the IEC type. It shocks me (excuse the pun) when I see Class2 equipment tested with a Class1 IEC lead without a separate test of the earth resistance of the portable mains lead.

Barney

Taking into consideration the sheer volume of medical devices in circulation, problems in accessing it for routine maintenance and the resources available in your typical Medical Physics/EBME medical equipment maintenance department.

Actually providing "evidence of failure" or failure to access equipment within the mandatory period may be taken as "an admission of guilt" under law if testing were mandatory.


But who decides on the intervals applied and to which devices? What would be "reasonable"? That's what I'm getting at when I say it would be difficult - managing what's, seen in the eyes of the law as, acceptable or not.

Don't worry, Lads, all this will change over-night (and who knows, perhaps resources will magically be made available), if the Health and Safety Tsars ever find the time to cast their hawk-like gaze over medical equipment!

Need I remind you that we exist in a State where even our finest police force, in the execution of their duties, does not escape the all-embracing Health and Safety laws?

I wonder if anyone from the H&SE lurks on this forum? I hope so.