Wiki first safety page - SECOND DRAFT for comment

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A THIRD draft has now been posted in a new thread ( ( here ) . I would be grateful if any further comments could be posted in that new thread. Thanks.

OK, following some very useful comments received this morning, herewith (below) Draft 2. I have done my best to take on board most of the comments received.

Some of my original (in italic) comments/questions/uncertainties still remain, so I’d welcome further input.

What do you think?

Kind Regards, John


THE RISKS

Electricity can, and does, kill, but much more commonly results in (possibly life-changing) serious burns and other serious injuries, including loss of fingers, limbs, sight etc, not necessarily directly related to the electric shock (i.e due to falls etc. caused by shocks). Residual current devices (RCDs) reduce, but do not eliminate, the risks of death and serious injury. Do not be complacent – catastrophes and tragedies really do happen.


BEFORE YOU START - GENERAL SAFETY ADVICE

Only undertake any electrical work if you are competent to do so – i.e. if you fully understand what you are doing and what safety precautions need to be taken. If in doubt, seek advice or professional assistance. If problems, uncertainties or things you don’t understand arise whilst you are doing the work, stop doing it and seek advice or professional assistance. Do not put yourself or those around you at risk by guessing or by trying to do things you don’t fully understand or which are beyond your capabilities.

Before working on any electrical circuit or item, you must disconnect (‘isolate’) it from the electricity supply and then confirm that it is no longer ‘live’. This is called ‘testing for dead’.

With the single exception of when you are ‘testing for dead’, you should never work on any electrical circuit or item which is, or may be, live. When ‘testing for dead’, be extremely careful not to touch any possibly live parts. Wearing rubber gloves (or, better than nothing, PVC ‘washing up’ gloves) will reduce the chance of your coming into contact with live parts. Never interfere with the electricity supplier’s fuse’s, the electricity meter or any of the cables to/from them.

When doing electrical work, you should not wear metallic jewellery or watches on your hands or wrists, or around your neck, and if you have metal-framed or metal-armed spectacles, use a neck cord so that they cannot fall into your work. Nasty accidents can, and do, happen as a result of such metallic items coming into contact with live electrical parts. Wherever possible do not work on an electrical installation unless someone else is around – just in case, despite all precautions, something happens to you.


BEFORE YOU START - SAFETY EQUIPMENT NEEDED - VOLTAGE DETECTOR

Before you undertake any electrical work, you should acquire a voltage tester for confirming that circuits are ‘dead’ and therefore safe to work on (‘testing for dead’). Ideally this should be a ‘two-pole voltage tester’ – either with a lamp or an LED/electronic display. A less satisfactory tool is a multimeter, set to a high (at least 300V) AC voltage range but, if you use this, be sure that the probes are such as to prevent you touching live parts when using them.[do we want that last sentence? – the problem is that ‘occasional DIYers’ simply aren’t often going to get a proper voltage detector, so maybe the best hope is that they may have, or get, a cheap multimeter?] ‘Neon test screwdrivers’ are unreliable to the point of being potentially dangerous (may fail to indicate voltage when voltage is present) and therefore should not be used to confirm that circuits are safe to work on (‘testing for dead’).


THE SAFE WAY TO UNDERTAKE ELECTRICAL WORK
To work safely, undertake the following steps, in the order given:

1: CONFIRM YOUR VOLTAGE DETECTOR IS WORKING PROPERLY
Do this by testing on a known voltage source [I am still not sure how to handle this. I wanted to add “for example....” here. but am not sure what to say. The CU will not normally be open. I suppose a lighting rose would be one possibility, but that would cause some confusions, and it would be a bit complicated to tell them to de-energise a sockets circuit, remove a socket face plate and pull it forward, then re-energise the circuit. I’m certainly not going to tell them some of the things I might do :) Any further thoughts/ideas?]

2: ISOLATE (DISCONNECT ELECTRICITY FROM) THE CIRCUIT YOU WILL BE WORKING ON
The safest approach is to switch off the ‘Main Switch’ of your Consumer Unit (CU) or fuse board, thereby switching off all electricity in your house. The next-safest approach is to switch of the ‘miniature circuit breaker’ (MCB), or remove the fuse, of the circuit you will be working on (plug-in Wylex MCBs can also be pulled out, like fuses, after switching off).[there are varying opinions about this, so further views would be welcome. Are we happy with that last sentence being there, or do we want to leave it as just ‘main switch’?]

3: IF POSSIBLE, ENSURE THAT THE ELECTRICITY CANNOT BE SWITCHED BACK ON WHILST YOU ARE WORKING
If you have removed a fuse or plug-in MCB, put it in your pocket. If the CU/fuse board is in a lockable room, lock it and put the key in your pocket. Locks for most MCBs and Main Switches are available. Consider putting a warning notice on the CU to warn against switching on the electricity. If none of those are possible, at least make sure that you warn anyone who might switch the electricity back on.

4: TEST THE CIRCUIT ‘FOR DEAD’ USING YOUR VOLTAGE DETECTOR
Test between Live and Neutral, between Live and Earth and between Neutral and Earth. Note that if you have isolated the circuit by switching off an MCB or removing a fuse, any RCD protecting the circuit will probably trip when you conduct the Neutral-Earth test, thereby removing electricity from circuits other than the one you are working on.

5: IF A POWER SOURCE IS STILL AVAILABLE, USE IT TO CONFIRM THAT YOUR VOLTAGE DETECTOR IS STILL WORKING PROPERLY
Unless you have a battery powered ‘proving unit’ (which you probably won’t have), this will generally not be possible if you have isolated using a ‘Main Switch’, and therefore have no electricity source available in your house. However, if a power source is available, it gives extra reassurance.do we want to suggest, per mfarrow suggestion, that they go through the isolate-test-reenergise-prove tester... cycle more than once?

6: DO THE WORK. AS FAR AS IS POSSIBLE, TREAT CONDUCTORS AS IF THEY WERE LIVE, EVEN THOUGH YOU HAVE ‘TESTED THEM FOR DEAD’
Wherever possible, avoid touching conductors at all, either directly or with non-insulated metal tools. Use insulated tools if possible. If you have to, or may, touch a conductor, try to avoid having your other hand anywhere near any conductor or anything metallic (behind your back or in your pocket is the ideal place for the other hand, although that’s not always practical) – the most dangerous electric shocks are those which go from one hand to the other.

Think, and then think again, at every stage. If in any doubt, don’t do it, or if doubts/uncertainties arise whilst you are working, stop doing it – and seek advice or professional assistance. It’s just not worth risking the life and limb of yourself and those around you.
 
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I'm starting to wonder whether, despite the suggestion and the fact that it contains a lot of valuable information, it's actually appropriate to add a link to HSG85 in the wiki, given that nearly half of its contents are in chapters entitled:
Deciding whether to work dead or live,
Actions common to both dead and live working, and
Working live
Thoughts?

Kind Regards, John
 
Very nice work John,
IMHO volt sticks should be added with neon testers as unreliable indicators of dead. It might be worth emphasizing that testing should be done on all three conductors (l-n, l-e, n-e,) cos the board maybe wired in reverse l-n!
 
Very nice work John, IMHO volt sticks should be added with neon testers as unreliable indicators of dead.
Thanks. I'm inclined to agree - but it's going to start getting difficult defining exactly what we are talking about. I'll have a think.
It might be worth emphasizing that testing should be done on all three conductors (l-n, l-e, n-e,) cos the board maybe wired in reverse l-n!
Do you mean that you think it needs more 'emphasis' than the current:
Test between Live and Neutral, between Live and Earth and between Neutral and Earth.
??? If so, what would you suggest?

Kind Regards, John
 
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Very nice work John, IMHO volt sticks should be added with neon testers as unreliable indicators of dead.
Thanks. I'm inclined to agree - but it's going to start getting difficult defining exactly what we are talking about. I'll have a think.
How about "Neon test screwdrivers (and 'non-contact voltage detectors') ..." ?

Kind Regards, John
 
How about "Neon test screwdrivers (and 'non-contact voltage detectors') ..." ?

Put pictures of them with appropriate wording, including the preferred devices.

" ...... worth a thousand words"
 
How about "Neon test screwdrivers (and 'non-contact voltage detectors') ..." ?
Put pictures of them with appropriate wording, including the preferred devices. " ...... worth a thousand words"
I did think of that, because I'm a great believer in "... worth a thousand words" but (a) I feared that littering the page with piccies might detratct from the structure and readability of the text, and (b) Given that there are a lot of products out there, I feared the possibility that people might think that anything which didn't look exactly like pictures of the 'no-no' devices were OK to use and/or that anything which didn't look exactly like the pictures of the 'preferred' devices wasn't OK!

What do people think?

Kind Regards, John
 
I'd like to get the first new safety page finalised and put into the wiki - as you've probably seen, I've already created a 'placeholder' for it in the wiki. I'm grateful for the valuable comments so far received, but have to say that I'm a little disappointed that more people have not commented - even if only to express their approval with what I'm proposing. It would seem a bit odd if crucial safety information in this forum was primarily the work of a non-electrician, without 'input' (even if only just 'approval') from an appreciable number of electricians! ... I feel a little 'lonely' in this task at present!

Apart from other matters of detail (which can be dealt with subsequently), there are three main outstanding issues that I need to resolve before I can post this page to the wiki, so I would be very grateful for thoughts/ideas about the following:

1...We really need to offer some advice, at least examples, as to how a DIYer should gain access to live conductors in order to 'prove' their voltage detector before using it. Most of us would probably use a 'test lead' of some sort, but I don't think it's really appropriate to suggest that to average DIYers (most wouldn't make one, anyway). Use of a ceiling rose is perhaps the 'simplest' answer, but complicated by the hazards associated with having to do it 'above one's head, probably on a ladder'. Thoughts, please!

2...Similarly, what (if anything) are we going to advise DIYers to do about 're-proving' their voltage detector after use if they have killed the whole electricity supply to the installation (e.g. with a main switch)? It is obviously unrealistic to expect them to have 'proving units'.

3...We have not really resolved the differences of opinion as to whether we should advise always isolating at the main switch (or equivalent), or whether we should mention using just a (nearly always SP - which results in some discussion re TT systems) MCB or fuse on the circuit for isolation. In my current draft, I've said that 'mains switch is best', but MCB/fuse is 'next-best'. Given the reality that many/most people will probably use the MCB/fuse, regardless of what we say, it seemed reasonable to mention it. What do you all think?

Kindest Regards, John
 
1...We really need to offer some advice, at least examples, as to how a DIYer should gain access to live conductors in order to 'prove' their voltage detector before using it. Most of us would probably use a 'test lead' of some sort, but I don't think it's really appropriate to suggest that to average DIYers (most wouldn't make one, anyway). Use of a ceiling rose is perhaps the 'simplest' answer, but complicated by the hazards associated with having to do it 'above one's head, probably on a ladder'. Thoughts, please!

I use the Kewtest Kewcheck r2 adaptor: http://www.testermans.co.uk/-kewtech-kewcheck-r2-socket-test-adaptor?manufacturer_id=16 . But I do have to unscrew the removable shrouds from the probes for the duration of proving, to make contact inside the 4mm sockets. They also do versions that will fit BC and ES lampholders.


2...Similarly, what (if anything) are we going to advise DIYers to do about 're-proving' their voltage detector after use if they have killed the whole electricity supply to the installation (e.g. with a main switch)? It is obviously unrealistic to expect them to have 'proving units'.

If they have no self contained voltage source then I can't see any other way to do this other than using the incoming terminal on the CU isolator. Not sure that is something we should recommend?

3...We have not really resolved the differences of opinion as to whether we should advise always isolating at the main switch (or equivalent), or whether we should mention using just a (nearly always SP - which results in some discussion re TT systems) MCB or fuse on the circuit for isolation. In my current draft, I've said that 'mains switch is best', but MCB/fuse is 'next-best'. Given the reality that many/most people will probably use the MCB/fuse, regardless of what we say, it seemed reasonable to mention it. What do you all think?

I agree we should say 'main switch is best' but if that is not possible due to need to maintains supply to other parts of the house then we should stress the need to test between all three conductors, not just L-N, just in case the circuit has reversed polarity and the wrong MCS has been turned off.
 
I use the Kewtest Kewcheck r2 adaptor: http://www.testermans.co.uk/-kewtech-kewcheck-r2-socket-test-adaptor?manufacturer_id=16 . But I do have to unscrew the removable shrouds from the probes for the duration of proving, to make contact inside the 4mm sockets. They also do versions that will fit BC and ES lampholders.
Yes, I imagine that most of us use either such adaptors and/or home-made test leads of one sort or another. However, I'm still not sure what we can reasonably advise DIYers to do - since most of them probably won't acquire such adapters, and I don't think we would want to be talking to them about 'making ip test leads'. What do you think?
If they have no self contained voltage source then I can't see any other way to do this other than using the incoming terminal on the CU isolator. Not sure that is something we should recommend?
I don't really think we should. Most DIY work won't requiring opening up the CU, so we don't really want to tell them to do that (with attendant dangers) just so that they can prove their voltage detector, do we? Virtually none of them will have/get a battery-powered proving unit, so I'm not sure that there is anything we can reasonably tell them - except that (as I've already said) it may not be possible if they have switched off the entire installation (with main switch etc.). I suppose they could go and use a neighbour's supply for 'after test proving', but that's probably not very realistic. If there is a saving grace, I suspect that (regardless of what we advise) many will not isolate their entire installation, so will have power to some circuits for that 'after' proving.
I agree we should say 'main switch is best' but if that is not possible due to need to maintains supply to other parts of the house then we should stress the need to test between all three conductors, not just L-N, just in case the circuit has reversed polarity and the wrong MCS has been turned off.
I think that's already all said in the present draft - so are you happy with that bit, as it is?

I have to say that the 'pragmatist' within me has some concerns about everything we're saying about 'testing for dead'. I seriously doubt that any appreciable number of DIYers (certainly not 'occasional' DIYers) are going to acquire a two-pole tester, no matter what we say/advise. Part of me therefore feels that we ought to be saying something about 'better than nothing' approaches to testing for dead, but since that would probably brings us back to the likes of neon screwdrivers, there's clearly a big problem there. I suppose that we might at least mention (in general, even if proper testing for dead has been undertaken) checking that the circuit 'appears dead' - i.e. lights no longer work or things plugged into sockets don't work. Any thoughts (from anyone)?

Kind Regards, John
 
Yes, I imagine that most of us use either such adaptors and/or home-made test leads of one sort or another. However, I'm still not sure what we can reasonably advise DIYers to do - since most of them probably won't acquire such adapters,

Hmm - they are only £14

and I don't think we would want to be talking to them about 'making ip test leads'. What do you think?

I think that if they can't make up a simple test lead to do that then shouldn't be contemplating doing electrical work anyway! Whether we should suggest that they do [make up test leads] is another matter, I guess.

I don't really think we should. Most DIY work won't requiring opening up the CU, so we don't really want to tell them to do that (with attendant dangers) just so that they can prove their voltage detector, do we?

Probably not.

I agree we should say 'main switch is best' but if that is not possible due to need to maintains supply to other parts of the house then we should stress the need to test between all three conductors, not just L-N, just in case the circuit has reversed polarity and the wrong MCS has been turned off.
I think that's already all said in the present draft - so are you happy with that bit, as it is?

I think perhaps "4: TEST THE CIRCUIT ‘FOR DEAD’ USING YOUR VOLTAGE DETECTOR" needs to stress the potential danger of not doing all three tests - I can see some DIYers who have some knowledge thinking 'what is the point of testing between N & E, I know they are linked at the main fuse/ at the substation''
 
Yes, I imagine that most of us use either such adaptors and/or home-made test leads of one sort or another. However, I'm still not sure what we can reasonably advise DIYers to do - since most of them probably won't acquire such adapters,
Hmm - they are only £14
Indeed thay are. However, I still think what I said is probably correct - as I've also said, I actually doubt that many will get a two-pole tester at all, let alone something to use it with.
I think that if they can't make up a simple test lead to do that then shouldn't be contemplating doing electrical work anyway! Whether we should suggest that they do [make up test leads] is another matter, I guess.
I think it is (another matter). In any event, what would we advise them to put on the end of this test lead - an unshuttered round-pin socket, or what?
I think perhaps "4: TEST THE CIRCUIT ‘FOR DEAD’ USING YOUR VOLTAGE DETECTOR" needs to stress the potential danger of not doing all three tests - I can see some DIYers who have some knowledge thinking 'what is the point of testing between N & E, I know they are linked at the main fuse/ at the substation''
Fair enough. I can strengthen that wording a bit.

Thanks for your input.

Kind Regards, John
 
You're absolutely right to point out the risk of injury from secondary effects, such as falling off the ladder. Is it worth adding that RCDs don't reduce the secondary risk at all?
 
You're absolutely right to point out the risk of injury from secondary effects, such as falling off the ladder. Is it worth adding that RCDs don't reduce the secondary risk at all?
Thanks. I'd be intertested to hear the views of others, but I'm personally inclined to think that it's probably best to keep that section about 'risks' as brief and simple as possible, and therefore wonder about the worth (on balance) of adding detail.

I'm not even convinced that what you suggest is actually strictly true. I suspect (but don't know for sure) that, particularly if the current through the person is modest (i.e. not much above 30mA) for what (in practice, not spec) is unlikely to be much more than 30msec might well reduce the chances of those secondary injuries, at least to some extent.

Is that your only comment on the draft? If so, I'm flattered :)

To all: I hope to be posting the third (hopefully 'final-pre-posting-into-wiki') draft later tonight - so, if there are any more comments, I'd be grateful if you could speak out soon. Thanks.

Kind Regards, John
 
Isolation can also be achieved by disconnecting cables inside CU?

As well as jewellery, tie back long hair??
 

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