Why is electricity more dangerous today than in 1992?

[SimonH2]

We already have plastic pins on many plug in items - typically DI appliances that don't need an earth. There's no problem making plastic pins the right size - it can only be a case of ignorance coupled with not caring.
Size is discussed at http://www.fatallyflawed.org.uk/html/size_matters.html, and there's a link near the bottom of the page to their table at http://www.fatallyflawed.org.uk/Socket_Cover_Pin_Dimensions_Feb_2018.pdf
Note in particular that there are many pins which are larger than they should be - and somewhere on the site I recall them quoting a review or comment elsewhere on the net from a mum saying that they had to use a hammer to fit the ones she'd bought it doesn't need much engineering knowledge to realise the risks to contact integrity of the socket when over-sized pins are inserted. Looking down the table I see not a single device listed with all dimensions correct - not one. Many get nearly all wrong, and one (Emmay Care) gets every single dimension wrong - yes you read that right, they managed to get EVERY dimension wrong which must be hard to do unless you are really trying. Note that this means all 3 of length x width x thickness of both earth and L/N pins, the pin tip profiles, the pin spacing, and the coverage around the L/N pins.

Ah yes, the hammer comment. Here it is (http://www.fatallyflawed.org.uk/html/clippasafe-boots-john_lewis.html) : "I bought these for a toddler group and had to throw them out. They needed a hammer to put into sockets and very difficult to remove. A total waste of money." Of course, this raises a point relevant to the original question - would someone have considered it reasonable to even try hammering such a device into a socket (say) 10 or 20 years ago ? is it a sign of the times that we now have people who would consider doing it ? The mind boggles sometimes.

EDIT: And oh yes, on that last page you can see the Plug Checker that is sold by Electrical Safety First. I keep one in my wallet - it's handy for that "and this is why it's dangerous" discussion when you can show how badly some things are out of spec.
At church I quietly told one of the church wardens that he'd better remove the ultrasonic rodent repellents he'd bought cheap off Amazon - on the basis that if he didn't I'd PAT them and they all fail on plug dimensions. Being able to show graphically how far out they were helped. We no have rodents back again though

 

[JohnW2]

We already have plastic pins on many plug in items - typically DI appliances that don't need an earth.

Sure - but, for obvious reasons, never all three pins! It was obviously just a 'long-shot' thought, but I just wondered whether, if they were made of fairly soft plastic, they might not slide so easily (i.e. might tend 'to get stuck') into the contacts. However, that thought is more-or-less put to bed by ...

Note in particular that there are many pins which are larger than they should be ...

However ...

Looking down the table I see not a single device listed with all dimensions correct - not one. Many get nearly all wrong, and one (Emmay Care) gets every single dimension wrong - yes you read that right, they managed to get EVERY dimension wrong which must be hard to do unless you are really trying. Note that this means all 3 of length x width x thickness of both earth and L/N pins, the pin tip profiles, the pin spacing, and the coverage around the L/N pins.

As we've discussed, that seems extraordinary, and (assuming not deliberate) totally unnecessary. Are the dimensions fairly consistent within one make, or are we perhaps seeing wide manufacturing variation in the saples that were tested/measured.

To what extent this is a significant issue (in relation to the 'big picture') is, in my opinion, far less certain - since it's very difficult to determine what the theoretical risks translate to in practice. In terms of 'children playing with them', whilst there have been reports (and videos) of 'near misses', I have not yet seen any reports of any child actually coming to harm - and, as for potential damage to sockets, it's extremely difficult to determine whether that is a significant safety issue.

In terms of the sockets, one partial 'saving grace' is that these things are most commonly used for long-term blanking off of 'unused' socket outlets - inserted once and left in place for years. Even if the pins are dimensionally incorrect, that might have less impact on the socket than does repeated insertion and removal of a correctly-dimensioned plug.

I also wonder about the 'dimensional conformity' of the pins of cheap plugs annd wallwarts etc - have you seen anything about that?

More generally, and analogous with what I've often said about RCDs, although obviously very well-intentioned, I can't help but wondering whether the considerable amount of effort and cost (in all senses) expended by FatallyFlawed in their campaign might not perhaps have reduced more injuries/deaths if it had been directed to some other safety-related issue. However, that';s essentially a rhetorical question, since the answer has to be 'who knows?'.

Kind Regards, John

 

[SimonH2]

As we've discussed, that seems extraordinary, and (assuming not deliberate) totally unnecessary.

Indeed, it is hard to imagine why someone would make zero effort to make it the right size when that would be a once-off effort of no more than an hour or two to look them up - as part of an expensive process of making injection moulding tooling. But then, one thing we've demonstrated to the Chinese is that we (collectively) will buy any old crap so perhaps that small amount of effort is seen as wasted. There is also the factor that they would need to know where to look, and also have access to the relevant BS which can be expensive.
I would hypothesise that they just grab whatever "BS1363 plus" they have to hand (it being some knock off non-compliant carp) and measure the pins with no idea what is important (e.g. pin tip profile) or not.

Are the dimensions fairly consistent within one make, or are we perhaps seeing wide manufacturing variation in the saples that were tested/measured.

I would be surprised if they varied much between individual units - injection moulding is relatively stable and it's actually hard to get out something different to what the mould normally produces. When I've looked (obviously looking through the packaging) I can't say there's been any difference that stands out.

To what extent this is a significant issue (in relation to the 'big picture') is, in my opinion, far less certain - since it's very difficult to determine what the theoretical risks translate to in practice. In terms of 'children playing with them', whilst there have been reports (and videos) of 'near misses', I have not yet seen any reports of any child actually coming to harm - and, as for potential damage to sockets, it's extremely difficult to determine whether that is a significant safety issue.

Agreed, very hard to quantify, but the big thing is that it's a zero cost, zero effort thing to just not introduce the previously non existant hazard in the first place. And of course, if one does damage a socket which subsequently overheats, it's unlikely that anyone would connect the two - an electrician replacing the socket wouldn't know about the previous usage and neither would a fire investigation officer.

In terms of the sockets, one partial 'saving grace' is that these things are most commonly used for long-term blanking off of 'unused' socket outlets - inserted once and left in place for years. Even if the pins are dimensionally incorrect, that might have less impact on the socket than does repeated insertion and removal of a correctly-dimensioned plug.

I'm not so sure. While there is clearly a risk of a damage event each time one is inserted, in the case of oversized pins it only needs the one event to cause the damage - how long it's left there is probably not significant. And of course, some of the artificially created risk is entirely due to the presence of the device - e.g. defeating the safety hutters and allowing foreign objects to be poked in.

I also wonder about the 'dimensional conformity' of the pins of cheap plugs annd wallwarts etc - have you seen anything about that?

No, I've not seen anything, but as I mentioned, someone bought some rodent repellents for church which had badly sized pins. I'd be very surprised if it wasn't very common. You may like to peruse Fatally Flawed's sister site PlugSafe which does in fact deal with this very issue.

More generally, and analogous with what I've often said about RCDs, although obviously very well-intentioned, I can't help but wondering whether the considerable amount of effort and cost (in all senses) expended by FatallyFlawed in their campaign might not perhaps have reduced more injuries/deaths if it had been directed to some other safety-related issue. However, that';s essentially a rhetorical question, since the answer has to be 'who knows?'.

As you say, nobody knows. However, persuading people to not artificially make their sockets dangerous has to be a worthwhile cause. Unlike (say) campaigning for RCDs on everything, there is no cost in NOT fitting these socket dangerifying devices - so really there's no financial argument for allowing or using them.

 

[JohnW2]

Indeed, it is hard to imagine why someone would make zero effort to make it the right size when that would be a once-off effort of no more than an hour or two to look them up - as part of an expensive process of making injection moulding tooling.

Yes, extremely odd, even for 'cheap and cheerful manufacturers.

I would be surprised if they varied much between individual units - injection moulding is relatively stable and it's actually hard to get out something different to what the mould normally produces.

Agreed. I just wondered.

Agreed, very hard to quantify, but the big thing is that it's a zero cost, zero effort thing to just not introduce the previously non existant hazard in the first place.

No cost in manufacturing etc. terms but, as I said, I was talking about the 'cost' (in all senses, particularly time/effort) in campaigning about such an issue - which 'cost'/effort might possibly result in avoidance of more injuries and deaths if it was re-directed to some other safety-related issue.

And of course, if one does damage a socket which subsequently overheats, it's unlikely that anyone would connect the two - an electrician replacing the socket wouldn't know about the previous usage and neither would a fire investigation officer.

Indeed - as I said, it would be extremely difficult (probably nigh on impossible) to get any useful data on possible consequences due to sockets having been damaged by these things.

I'm not so sure. While there is clearly a risk of a damage event each time one is inserted, in the case of oversized pins it only needs the one event to cause the damage - how long it's left there is probably not significant.

As I implied, I'm also anything but sure. I wasn't thinking about 'how long it's left there but, rather, the number/frequency of insertions/removals.

As you say, nobody knows. However, persuading people to not artificially make their sockets dangerous has to be a worthwhile cause. Unlike (say) campaigning for RCDs on everything, there is no cost in NOT fitting these socket dangerifying devices - so really there's no financial argument for allowing or using them.

As above, although there are obviously direct (and massive) financial issues with universally fitting RCDs, I was talking about the cost/effort of campaigning - and, in particular, the relative value (in terms of reducing injuries/deaths) of expending the same amount of time/efforts/cost in campaigning about different issues.

Kind Regards, John