Table Lamp PAT Test advice.

[RandomGrinch]

given that, as we have both said, the absence of a Class II marking means that the item must be consider (and inspected/tested) as Class I.

I've never said 'must'!
I stated the guidance says, it should be 'assumed' to be class 1 - a slight difference.
Under the guidance we are also free to select appropriate tests.

...and as I've said before, given an appropriate RA, a class 1 appliance such as a PC server, or the equipment in an AV cabinet, may not even need a PA Test within its expected lifetime.

However, if one has no particular reason to believe that it ever did have a Class II marking, then I would question whether it would be appropriate for a PA tester (or anyone else) to decide (by personal judgement) that it could be considered (and inspected/tested) as a Class II item.

Ultimately, we are not determining whether an appliance is class 1 or 2. We are determining an appropriate level of risk, of the appliance causing harm. This does require robust RA's and SOP's with a feedback mechanism, suitable test equipment and trained testers.

This may not work for everyone, but it is standard practice in our large institution and many like it.

 

[JohnW2]

I have no alternative; I am just saying the situation is unsatisfactory - but if your 'anyone' is relying on a sticker/marking as gospel then it is itself dangerous.

It's certainly not ideal. However, as I implied, there are countless things in this world which are 'unsatisfactory', but unless someone has suggestions as to what would be 'more satisfactory', there's not really any useful discussion to be had!

Just a semantic question: if someone earths the metal casing of a Class II product, is it still Class II?

As I have implied, I think that question is essentially moot. The default situation is that anything with exposed-c-ps has to have those exposed-c-ps earthed. However, there is a dispensation that, if certain conditions are fulfilled, that earthing is not required (what we call 'Class II'). However, if the exposed-c-ps are earthed, then there is no need to consider that dispensation - so, as I said, the question of "what 'Lass' is it?" is really moot.

That's why (unlike you) I've never been particularly happy with those MIs of items manufactured as 'Class II' which say that the item "MUST not be earthed". Sure, there is a general truth that it is theoretically undesirable to have any unnecessarily earthed metal in an environment, but one might just as well make a "MUST not be earthed" statement in relation to baths/sinks/window frames/whatever (which ione never sees) - even though there's nothing about a Class II device being 'electrical' in nature which makes tits exposed-c-ps different from any of those other bits of 'exposed metal'.

Kind Regards, John

 

[plugwash]

The default situation is that anything with exposed-c-ps

IIRC the BS7671 definition at least of "exposed conductive part" is not just any conductive part that is exposed, but a conductive part that is liable to become live under fault conditions.

Which really brings us back to the same problem, how does one determine in the field whether a conductive part is "liable to become live under fault conditions", without access to detailed design documentation and risk assements of the devices design.

 

[JohnW2]

I've never said 'must'! I stated the guidance says, it should be 'assumed' to be class 1 - a slight difference.

Agreed ... "slight"

Under the guidance we are also free to select appropriate tests.

We are. However, as I said, I don't think it would be appropriate to omit the tests which would be required for a Class I item unless one had pretty good reason to believe that it actually qualified as 'Class II (e.g. if one knew that there had previously been a 'Class II' label, but that it had 'come off' and/or associated documentation explicitly said that it was Class II), would you?

Otherwise (in the absence of marking/documentation indicating that it was 'Class II'), I'm not sure how anyone could (at least, in most cases) use their judgement/RA to decide that Class I inspection/testing was not required. I've personally never really got to the bottom of what actually qualifies as 'reinforced insulation', and therefore certainly could not tell if that was what I was dealing with - and, as for 'double insulated', it would usually be impossible to ascertain whether that were present without dismantling the item, wouldn't it? Or, perhaps, given ...

Ultimately, we are not determining whether an appliance is class 1 or 2. We are determining an appropriate level of risk, of the appliance causing harm.

... are you perhaps going as far as suggesting that a Risk Assessment can over-ride the whole concept of Class I/II - i.e. that the RA might lead you (somehow!!) to conclude that an item was adequately 'safe' without its exposed-c-ps being earthed, despite the fact that you could not be sure that it had either double or reinforced insulation?

Kind Regards, John

 

[JohnW2]

IIRC the BS7671 definition at least of "exposed conductive part" is not just any conductive part that is exposed, but a conductive part that is liable to become live under fault conditions.

Indeed so, but, as you go on to say...

... Which really brings us back to the same problem, how does one determine in the field whether a conductive part is "liable to become live under fault conditions", without access to detailed design documentation and risk assements of the devices design.

Exactly - or, perhaps, if one dismantles the item. However, the only way in which I can see an exposed-c-p not being "liable to become live under fault conditions" is if it were actually 'Class II' (i.e. if there were double or reinforced insulation between the exposed metal and any live parts - in which case one would expect it to be documented/marked as "Class II", wouldn't one?

If the manufacturer is not confident enough that the insulation is either double or adequately 'reinforced' to claim the product is 'Class II', then I think it would have to be a fairly brave (or stupid) person who nevertheless assumed that it could be regarded as Class II, wouldn't it?

Kind Regards, John

 

[RandomGrinch]

.. are you perhaps going as far as suggesting that a Risk Assessment can over-ride the whole concept of Class I/II - i.e. that the RA might lead you (somehow!!) to conclude that an item was adequately 'safe' without its exposed-c-ps being earthed, despite the fact that you could not be sure that it had either double or reinforced insulation

I wouldn't go quite that far!
But, I would say, there are circumstances where an RA could determine a test frequency that is outside of the useful life of the appliance; in this instance, whether a class 1 appliance has an exposed-c-p that is earthed, or not, may never be determined!
Edit: sort of like Schrödinger's PAT???

I like the HSE PAT guidelines.
They are not overly stringent, they have an emphasis on end user checks and education. They also allow for flexibility when dealing with outlier cases, such as foreign equipment, etc.
And there is also an expectation that appliances are supplied as fit for purpose - as if not, other laws apply.

Otherwise (in the absence of marking/documentation indicating that it was 'Class II'), I'm not sure how anyone could (at least, in most cases) use their judgement/RA to decide that Class I inspection/testing was not required.

In the OP's case, the use of a 2 core cable strongly suggests that it would be a class 2 appliance . And....

An appliance such as the OP's (If I had a legitimate concern), would have an individual test regime - a visual inspection, an insulation test, a touch leakage test and increased testing frequency

 

[JohnW2]

I wouldn't go quite that far! ...

I doubted that you would - as you presumably realised, my question was essentially rhetorical !

... But, I would say, there are circumstances where an RA could determine a test frequency that is outside of the useful life of the appliance; in this instance, whether a class 1 appliance has an exposed-c-p that is earthed, or not, may never be determined!

That may be 'within the guidelines', but do you really believe it is satisfactory, or even necessarily 'acceptable'? You seem to be saying that if there is an item which, if tested, would be deemed to be 'unsafe' (would fail the PA test), you can avoid that being discovered by deciding that it doesn't need testing until beyond its useful/expected lifetime - is that correct?

I like the PAT guidelines. .... They are not overly stringent, they have an emphasis on end user checks and education. They also allow for flexibility when dealing with outlier cases, such as foreign equipment, etc.

I would be much more inclined to sympathise with that viewpoint if there were strict, and fairly demanding, requirements in relation to who could do this inspection/testing, together with robust regulation and oversight of those who did.

In the OP's case, the use of a 2 core cable strongly suggests that it would be a class 2 appliance .

Very probably. However, if you acted upon that assumption, would you not be at risk of missing one of the most dangerous of situation which one would hope the inspection/testing would detect - namely a product (perhaps a 'dodgy import') with exposed-c-ps, but no double/reinforced insulation, yet with not even a CPC in the supply cable?

Kind Regards, John

 

[BQW]

I think this thread has gone off course, a bit.
On my first visual inspection of this lamp in question, my suspicions were aroused by what I perceived as the attached poor quality quality mains flex.
I initially thought it had been rewired with that clear two core speaker cable, but further inspection proved it was double insulated, but neither core was colour coded or marked, so I then started to look for a BS number on the outer sheath, the only markings I can see are the CSA of 0.75, nothing more, no voltage rating, nothing .
I am sure I was informed when I did my CG277, that all flexible cables like T&E etc must have a BS number.
Since I inspected this lamp, curiosity has made me look at several examples of Flex, to find a BS number, but I cant find any, was I misinformed on that one ?
So back to my original question, I failed it after some thought on the mains flex not being colour coded and what I perceived as poor quality, then to back up my quality suspicions no BS number .
So leaving out the class 1 or 2 argument possible the stickers fell of, was I right ?

 

[RandomGrinch]

I think this thread has gone off course, a bit.

Sorry, I'm afraid it often does in this forum

So leaving out the class 1 or 2 argument possible the stickers fell of, was I right ?

As far as I'm concerned, taking guidance into consideration, you are right.
You have legitimate concerns and you can justify your decision.
But (and without being in front of the appliance), it may be possible that another person, with different experience and different tests available could pass the appliance.
Again, within the guidance as I see it, that may also be 'right' if they can justify their decision.

I'm sure others may disagree with me though!

Edit: ...and some may not even notice an issue to begin with and pass it without a second thought. Top marks for diligence

 

[RandomGrinch]

would be much more inclined to sympathise with that viewpoint if there were strict, and fairly demanding, requirements in relation to who could do this inspection/testing, together with robust regulation and oversight of those who did.

That would definitely improve standards, but at what cost?
The HSE is encouraging a pragmatic approach, reducing risks in a 'Reasonably Practicable' way.
In my case, do we employ our
two electrical engineers (on academic salaries), full time to maintain and inspect our 15'000 appliances, or is the workload shared between a team of technicians and apprentices?
Is the extra cost justifiable to catch 99.99% of failures, over 99.9%?

With health and safety, there is always a heirarchy leading up the management levels and including the HSE.
As I have said before, a feedback loop is essential for RA's etc.
If the current PAT system was inadequate, too many failures would show up and the system would have to change.

However, if you acted upon that assumption, would you not be at risk of missing one of the most dangerous of situation which one would hope the inspection/testing would detect - namely a product (perhaps a 'dodgy import') with exposed-c-ps, but no double/reinforced insulation, yet with not even a CPC in the supply cable?

Yes, you would be at risk, but as ever that risk can be assessed.

The HSE guidance states there is a legal duty on suppliers and manufacturers to supply safe equipment.
If PAT was to check that equipment was manufactured correctly, that would require a whole new skillset and would duplicate the efforts of other agencies.

Yes, PAT can catch these dangerous outliers, but that's a bonus, rather than a mandate.
In my case, anything that comes from eBay/unapproved suppliers gets a thorough going over.

As in the OP's case, the appliance came from 'a well known large retailer' - although items do slip through the net, the 'Swiss cheese' model of safety would mean 'dangerous' items may be caught at many stages.
Those that do make it through and are not eventually recalled are (hopefully) so rare, that we get back to, is finding them 'reasonably practicable'.

 

[JohnW2]

That would definitely improve standards, but at what cost? .... The HSE is encouraging a pragmatic approach, reducing risks in a 'Reasonably Practicable' way. .... Is the extra cost justifiable to catch 99.99% of failures, over 99.9%?

We've been through essentially the same discussion (including that about 'requirements' and regulation), repeatedly and at length, in relation to EICRs and, indeed, even more generally in relation to "Part P" and BS7671.

For a start, risk-based cost-effectiveness assessments in relation to matters of safety are not necessarily all that 'rational' if viewed dispassionately. Even in the case of 'obvious' things like RCD protection, I've often been known to suggest that the billions spent on such devices could have 'saved far more lives' if diverted to some totally different safety-related issue.

One important issue (with both EICRs and PA tests) is that there are costs on both sides of the fence. Those 'testers' who, either to protect their backsides or (particularly with EICRs) to 'generate work', 'err' very much on the side of 'failing' things can result in considerable ('unnecessary') expenditure on the part of the owners of the equipment/installation.

However, I think the bottom line is that if we have decided that we want EICRs and PA testing etc., then it needs (in general, not just in situations like yours) to be 'fit for purpose' - which, to my mind, probably necessitates far more regulation than currently exists.

Is the extra cost justifiable to catch 99.99% of failures, over 99.9%?

I would imagine that, in the PA testing world in general, those figures are way too optimistic!

In my case, do we employ our two electrical engineers (on academic salaries), full time to maintain and inspect our 15'000 appliances, or is the workload shared between a team of technicians and apprentices?

You appear to be talking about the very 'highest end' of the spectrum of PA testing in general in the real world. If you ask Mr Google "how do you become a PAT tester?" (the redundant/repetitive "T" considerably increases the number of hits ), one gets literally thousands of hits, many of which say things along the lines of this one ...

I have no previous electrical knowledge; will I be OK to attend a PAT course?
You do not need to have any previous electrical experience to attend our one day PAT Competent Person course. We are confident we can train most people and we deliberately keep our class sizes small to ensure that no one gets left behind. If you would like to prepare for the course we would advise reading our training manual beforehand. You can access the training manual from your course account.

... hence my views about the need for sensible "requirements" and regulation.

With health and safety, there is always a heirarchy leading up the management levels and including the HSE. As I have said before, a feedback loop is essential for RA's etc.

As I implied above, there is often no real 'heirarchy' - just an individual (whose 'training' in matters electrical may only have taken one day) and the HSE itself.

If the current PAT system was inadequate, too many failures would show up and the system would have to change.

As with EICRs, in the absence of regulation and audit, we really can't have a clue as to how many 'failures' there might be.

The HSE guidance states there is a legal duty on suppliers and manufacturers to supply safe equipment. ... If PAT was to check that equipment was manufactured correctly, that would require a whole new skillset and would duplicate the efforts of other agencies. .... As in the OP's case, the appliance came from 'a well known large retailer'

Hmmm. In the eyes of those commissioning PA tests (and quite probably the eyes of HSE) 'safety is safety', and if something is unsafe, they don't really care whether that is due to a design/manufacturing fault or to a deterioration or misuse whilst in service, do they?

As in the OP's case, the appliance came from 'a well known large retailer' - although items do slip through the net, the 'Swiss cheese' model of safety would mean 'dangerous' items may be caught at many stages. .... Those that do make it through and are not eventually recalled are (hopefully) so rare, that we get back to, is finding them 'reasonably practicable'.

I'm somewhat confused. Yous seem to be advocating and agreeing with a very sensible and reasonable (essentially 'common sense') risk-assessment-based approach. However, in relation to the OP's lamp, you seem to be agreeing with him that (despite the fact that it is brand new from "a well-known large retailer", and hence ''should be safe') it should fail a PA test, not because it 'may' be an unearthed Class I item but, rather, because it's (insulated and sheathed) power cable does not have the correct insulation colours or a BS marking (and "perceived as poor quality", whatever that means). Does that really mean that your 'risk assessment' leads you to believe that either of those 'technicalities' represents an appreciable risk to users??

Kind Regards, John

 

[SimonH2]

So back to my original question, I failed it after some thought on the mains flex not being colour coded ...

Does the cable need to be colour coded if it's only two core AND the device on the end of it is polarity insensitive ? For example, if there's a BC lampholder on the end, it makes zero difference which pin is L and which is N.

If you ask Mr Google "how do you become a PAT tester?" (the redundant/repetitive "T" considerably increases the number of hits ), one gets literally thousands of hits, many of which say things along the lines of this one ... ... hence my views about the need for sensible "requirements" and regulation.

I have done a course on PA testing when my previous employer decided it might be a useful extra offering to be able to test the (IT) equipment we already looked after for many clients. Provided the person did have a few brain cells switched on, I didn't think it was too bad - the course I did made it clear about visual inspection, how to interpret the lights on the pass/fail tester, keeping an equipment register, etc. IF the person went into it with an attitude of wanting to do it right, then I think they would have been able to with just this training. Obviously, we all know what that "IF" can mean ...

 

[JohnW2]

I have done a course on PA testing when my previous employer decided it might be a useful extra offering to be able to test the (IT) equipment we already looked after for many clients. Provided the person did have a few brain cells switched on, I didn't think it was too bad - the course I did made it clear about visual inspection, how to interpret the lights on the pass/fail tester, keeping an equipment register, etc. IF the person went into it with an attitude of wanting to do it right, then I think they would have been able to with just this training. Obviously, we all know what that "IF" can mean ...

Does that mean that you feel it is satisfactory for someone with "no previous electrical experience" to undertake PA testing after undergoing a "one-day course"?

Kind Regards, John

 

[SimonH2]

Depends on tbe course and the attitude of the student.
As I said, the course I did was (IMO) adequate for someone with the right attitude. The tester is a simple go/no-go unit to use and hence needs no interpretation.
Clearly, if someone isn't interested in doing things properly then it doesn't really matter what the course is like as they'll just "carry on regardless".

 

[JohnW2]

Depends on tbe course and the attitude of the student. As I said, the course I did was (IMO) adequate for someone with the right attitude. The tester is a simple go/no-go unit to use and hence needs no interpretation. .

True, but has been said (and I can well believe this to be the case) ...

Class 2 appliances mostly fail on visual inspection...

Unless you are aware of some sort of 'tester' machine that can undertake a "go/no-go" visual inspection, that might present a potential problem in relation to someone whose entire electrical knowledge and experience was based on a one-day course, mightn't it?

Kind Regards, John