Wiki first Safety page - FIRST DRAFT for comment

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Edit: PLEASE NOTE: I have now posted the second draft in a separate thread, so would be grateful if any further comments could be made in that thread. Thanks.

OK, following discussions in other threads, herewith (below) my stab at a rough first draft of a wiki page to ‘replace’ the three posts in the ‘ELECTRICS SAFETY’ sticky. I have tried to cover all the main topics/points which are in those three posts, and have added some material of my own, trying to put all the material into a fairly structured form. There are a number of comments/questions from me (in italics). Formatting can be sorted out if/when the wiki page is created.

Please provide as much input as you can, by way of comments etc. You may think I’ve done it completely wrong, and certainly may disagree with some things I’ve written – remember that I am not ‘qualified’ to talk/write about matters electrical. Given that ‘twas me that wrote it, you may well feel that it is too verbose :) Whatever, please let me know what you think, in as much detail as possible. There are obviously lots of other issues/topics I could have covered, but they are perhaps best left for other ‘pages’ – but you may nevertheless want tyo comment upon the ‘scope’ of this page.

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. 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.

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.


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. 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 and should not be used to confirm that circuits are safe to work on.


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 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 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).[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.

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.

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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Very good.

A few comments

Neon screwdrivers are less than un-reliable...... they are dangerous when they give no indication when the conductor being tested is live.

Some serious injuries are caused by shock induced falls when balancing on unstable steps chairs etc.

Avoid working alone in case an accident occurs,

Make notes, take photos of the work done for future reference
 
One testing for dead could using a lead set be an option to defeat the shuttered socket? Just a thought.

Although the Neon Screwdriver should not be used to test for dead, it is a good secondary device for highlighting things like shared neutrals I always use one as my terminal driver. The Martindale four neon tester will work in the same way as a neon screwdriver if one holds the wandering lead tip in ones hand in the same way as touching end or clip on a Neon screwdriver yet we do not condemn the Martindale tester. With volt sticks these will light rubbed on a jumper yet sold to test voltage. Warn against relying on Neon Screwdriver yes but telling people not to use one is very different.

Slight worry is isolating with fuse of MCB which are single pole. OK with TN but one could get quite a shock with TT from neutral.

The comments about alone working and photos are good and shock induced falls are good.

I do like the plug in tester for the DIY guy. Little chance he will get bad connection. I like many others often use a radio to locate which MCB controls a circuit so I can hear when it becomes dead the plug in tester is really an official device to do same job.
 
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and shock induced falls are good.
They do at least break the connection :cry:

You and I ( and a few others ) know how the neon screwdriver works and therefor we also know when it will give a false indication. The average DIYer does not have our experience so I stick to my opinion that neon screw drivers should not be a tool for the DIYer.
 
and shock induced falls are good.
They do at least break the connection :cry:

You and I ( and a few others ) know how the neon screwdriver works and therefor we also know when it will give a false indication. The average DIYer does not have our experience so I stick to my opinion that neon screw drivers should not be a tool for the DIYer.

I have to agree that all too often it is used incorrectly so maybe best is not to mention the device.
 
Thorough work there John. A few ideas to ensure the message gets across.


'Test for dead' should be a consistent message throughout. Those exact words in quotation only when referring to such an activity.

'Test for dead' should be introduced in the BEFORE YOU START - GENERAL SAFETY ADVICE section before it is mentioned in the last paragraph. A short sentence like "Always 'test for dead' before working on any piece of electrical equipment, to ensure it is safe to do so".

In BEFORE YOU START - SAFETY EQUIPMENT NEEDED - VOLTAGE DETECTOR the exposed ends of the probes should ideally be no longer than 2mm long.

For 1: CONFIRM YOUR VOLTAGE DETECTOR IS WORKING PROPERLY I see nothing wrong in what you have suggested wrt write about proving the device using a socket circuit, although a ceiling rose is preferred as a metallic socket and non-GS38 leads are a dangerous combination. As long as it is clear that the circuit you are using to prove should be dead whilst any covers or accessories are moved or removed, that should be OK. This 'disconnect supply before removing cover' message should be part of general rules and the process.

For 2: ISOLATE (DISCONNECT ELECTRICITY FROM) THE CIRCUIT YOU WILL BE WORKING ON if they do not have an earth wire going back to the main fuse or the cable supplying it, it is likely they have a TT earth and should switch off the main switch anyway (I'm ignoring the rare occurence of DP MCBs/RCBOs).

In 4: TEST THE CIRCUIT ‘FOR DEAD’ USING YOUR VOLTAGE DETECTOR don't forget that on split load or TT boards, other circuits covered by the RCD will loose their supply when the RCD trips.

For 5: IF A POWER SOURCE IS STILL AVAILABLE, USE IT TO CONFIRM THAT YOUR VOLTAGE DETECTOR IS STILL WORKING PROPERLY you could always suggest re-energising the circuit you're working on to test for live and then repeating the isolation process one more time, as it's better than nothing.

I suggest adding links to GS38 and HSG85, and also reading them for your own benefit. Note that permitry is still recommended even in LV or <=600V applications, but very few people follow that advice, especially if sole working.
 
I have to agree that all too often it is used incorrectly so maybe best is not to mention the device.
Because it is unreliable but is sold as a voltage tester the DIYer must be made aware that it may fail to indicate that a circuit is live.
 
And point out that it relies on the person using it becoming part of the circuit.

IF it should go wrong inside the user might be exposed to full mains voltage.
 
Very good. A few comments ... Neon screwdrivers are less than un-reliable...... they are dangerous when they give no indication when the conductor being tested is live.
Thanks. I'll strengthen the wording about neon screwdrivers a bit.
Some serious injuries are caused by shock induced falls when balancing on unstable steps chairs etc.
Indeed - it was just a question of knowing where to stop. I did mention 'other serious injuries' without saying that they were necessarily 'electrical'. I similary did not explicitly mention thermal damage to muscles and organs - again, because one has to 'stop' somewhere. I'll give some thought to this.
Avoid working alone in case an accident occurs,
Yes, that's probably worth having, but I suppose it will have to be an "If/wherever possible ...." one.
Make notes, take photos of the work done for future reference
Important, but I'm not sure that this page, basically about 'safe working' practices, is the place for it, is it?

Kind Regards, John
 
One testing for dead could using a lead set be an option to defeat the shuttered socket? Just a thought.
You and I would do that, but I doubt that many DIYers would, and I'm far from sure that we should even be suggesting that they should. What would you say they should put on the other end of the lead - an unshuttered (round pin) socket, perhaps (with attendent hazards)? I presume like most readers of this, I have various lead sets etc., and various 'practices' for doing this, but I'm far from convinced that any of them should be mentioned to DIYers.
Although the Neon Screwdriver should not be used to test for dead, it is a good secondary device for highlighting things like shared neutrals I always use one as my terminal driver. ... Warn against relying on Neon Screwdriver yes but telling people not to use one is very different.
Again, I think you are talking about 'us'. I somehow doubt that there are many electricians who don't carry, and sometimes use, a neon screwdrivers, for various purposes which they understand. However, I think the potential shortcomings, and hence risks, are such that I personally think we should go with 'the simple' (as previously mentioned by yourself) and tell DIYers never to use a neon screwdriver for any testing.
Slight worry is isolating with fuse of MCB which are single pole. OK with TN but one could get quite a shock with TT from neutral.
This is a question I raised and would welcome further comments. The reality almost certainly is that most will just use MC/fuse - and 'unnecessarily' working with poor lighting because one had used a main switch could itself introduce hazards. I personally think that the theoretical risk of a significant shock from a TT neutral is very much overplayed, but others may well disagree. I would welcome more views about this question.
I do like the plug in tester for the DIY guy. Little chance he will get bad connection. I like many others often use a radio to locate which MCB controls a circuit so I can hear when it becomes dead the plug in tester is really an official device to do same job.
Are you suggesting that we should advocate either of those for 'testing for dead'?

Kind Regards, John
 
You and I ( and a few others ) know how the neon screwdriver works and therefor we also know when it will give a false indication. The average DIYer does not have our experience so I stick to my opinion that neon screw drivers should not be a tool for the DIYer.
I have to agree that all too often it is used incorrectly so maybe best is not to mention the device.
I fairly strongly disagree with that. Neon screwdrivers are so ubiquitous, and are the think which most 'lay' people would probably turn to to 'test for dead', that I think it's imperative that we 'mention' them, so we can tell them not to use/rely on them for 'testing for dead'.

Kind Regards, John
 
Thorough work there John. A few ideas to ensure the message gets across.
Thanks. I've commented on your helpful/thoughtful comments below. Some of your comments raise the question of 'where do we stop'/'how far do we go', in order to create a document short enough to be read and understood, and with the crucial points clearly visible, rather than potentially hidden amongst 'explanatory detail'...
'Test for dead' should be a consistent message throughout. Those exact words in quotation only when referring to such an activity.
That's a reasonable suggestion.
'Test for dead' should be introduced in the BEFORE YOU START - GENERAL SAFETY ADVICE section before it is mentioned in the last paragraph. A short sentence like "Always 'test for dead' before working on any piece of electrical equipment, to ensure it is safe to do so".
'Testing for dead' is already the subject of the second paragraph, and I think the first paragraph ('don't do it if you're not competent etc...') has to remain as the first paragraph. Are you perhaps suggesting that I should add an 'always test for dead' sentence/paragraph between the current first and second paras? If so, I agree that would be reasonable.
In BEFORE YOU START - SAFETY EQUIPMENT NEEDED - VOLTAGE DETECTOR the exposed ends of the probes should ideally be no longer than 2mm long.
Valid point - but is that perhaps 'excessive detail'?
For 1: CONFIRM YOUR VOLTAGE DETECTOR IS WORKING PROPERLY I see nothing wrong in what you have suggested wrt write about proving the device using a socket circuit, although a ceiling rose is preferred as a metallic socket and non-GS38 leads are a dangerous combination. As long as it is clear that the circuit you are using to prove should be dead whilst any covers or accessories are moved or removed, that should be OK. This 'disconnect supply before removing cover' message should be part of general rules and the process.
I'll think about this one, but would welcome more views about it. 'Ensuring' that a circuit is dead before removing covers in order to be able to undertake 'tests for dead' is obviously a potentially confusing oxymoron, both in terms of words and concepts!
For 2: ISOLATE (DISCONNECT ELECTRICITY FROM) THE CIRCUIT YOU WILL BE WORKING ON if they do not have an earth wire going back to the main fuse or the cable supplying it, it is likely they have a TT earth and should switch off the main switch anyway (I'm ignoring the rare occurence of DP MCBs/RCBOs).
I fear this might be 'too much detail' for many, and therefore wonder whether (although I suspect many will ignore it) eric's view of just saying that one should always use the main switch might be the 'simplest' and hence most easily understood. Mind you, as I've written to eric, I do personally think that the risks of SP isolation with TT are probably overplayed - and may well be less than the risks associated with working with poor lighting when a main switch has been used!
In 4: TEST THE CIRCUIT ‘FOR DEAD’ USING YOUR VOLTAGE DETECTOR don't forget that on split load or TT boards, other circuits covered by the RCD will loose their supply when the RCD trips.
I thought that was the point I was making - is it not clear enough? I will perhaps add a few words.
For 5: IF A POWER SOURCE IS STILL AVAILABLE, USE IT TO CONFIRM THAT YOUR VOLTAGE DETECTOR IS STILL WORKING PROPERLY you could always suggest re-energising the circuit you're working on to test for live and then repeating the isolation process one more time, as it's better than nothing.
I suppose so, but that is obviously a potentially endless cycle - what do others think?
I suggest adding links to GS38 and HSG85, and also reading them for your own benefit. Note that permitry is still recommended even in LV or <=600V applications, but very few people follow that advice, especially if sole working.
I've read GS38, but not HSG85 - are both available on-line for 'linking'?

Kind Regards, John
 
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.

There isn't always a main switch, its fairly common, particularly in older places, to have several fuseboards that need turning off before everythings isolated.
 

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