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Topic Title: 411.3.3
Topic Summary: No RCD risk assessment
Created On: 07 February 2015 08:38 AM
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 07 February 2015 08:38 AM
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Zs

Posts: 3814
Joined: 20 July 2006

Good Morning,

My copy of the big yellow bumper fun book arrived yesterday, in paper format.

You know we've been talking about the risk assessment which is required in order to permit exception from the omnipotent RCD requirement? It has been my understanding that this risk assessment must be provided by the client.

Well, what it actually says is this;

An exception to (i) is permitted:

(a) where, other than for an installation in a dwelling, a documented risk assessment determines that the RCD protection is not necessary, or

(b) for a specific labelled or otherwise suitably identified socket outlet provided for connection of a particular item of equipment.

So, it doesn't actually say anything there about who prepares the risk assessment. I was expecting it to use a term such as duty holder or the like.

Does anyone know anything about a second level of regs somewhere which states that risk assessments, perhaps beyond the installation risks, are always prepared by the client or the like? I can see that it would be best all round if they prepare it but is that a given?

I'm wondering about this now and thinking that we may have been propagating our own new modern myth?

I'd appreciate your interpretation of this. I have one on the go at the moment (commercial) and it would be nice to be properly informed. We are committed to amd 3 design.

thanks,

Zs
 07 February 2015 09:13 AM
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Dtw21

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Surely it is down to the duty holder/health and safety bod, to be the one responsible for preparing a risk assessment. It's their site, their staff.
I would think they would be in the best position to write the risk assessment knowing the full extent of the site function etc...

Probably wouldn't be a bad idea to consult the person preparing the RA, with your electrical knowledge.
 07 February 2015 09:35 AM
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alanblaby

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I can see a lot of Risk Assessments being rapidly done after July, assuming that the new GN3 recommends non-compliance to be a C2.
(have you had any input on this version Zs?)
I was at a major Showground late last year - mostly built in the 70/80's, with very few RCDs in place, and mostly fed from defunct/obsolete 3 phase boards. It would cost tens of thousands to upgrade the lot, for very little benefit - mostly fixed equipment, or feeds to exhibitor stands, which themselves have RCD protection via a 'garage' style CU.

They wont upgrade, they'll write down that a RCD isnt necessary.
 07 February 2015 10:16 AM
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phantom9

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Hi Zs

If you look at Note 3 of that Reg it refers you to Appendix 2 item 10.

"The Management of Health and Safety at Work Regulations 1999...require employers and self-employed persons to assess risks to workers and others who may be affected by their work or business...."

What puzzles me is 411.3.3 (b)

It says that if you label or suitably identify the outlet as specific to an item of equipment you don't need an RCD. What's the reasoning here? Presumably if you label kitchen sockets as "fridge", "washing machine", "kettle", "toaster" etc. they are excepted from being RCD protected. My point being the act of labelling or identifying a socket outlet in this way doesn't necessarily prevent other items of equipment from being plugged in to that outlet. I find the Regs very irritating, don't you? Humph. And I don't understand why the very act of identifying a socket for an item of equipment changes the characteristics of the circuit to preclude the need for an RCD. It doesn't make any sense to me. What is the reason for using the RCD in the first place if they are allowing you to omit it by virue of a label? Humph again.
 07 February 2015 10:52 AM
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OMS

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Start by asking what is the purpose of the RCD - ie who is being protected from what

If it's for additional protection due to the carelessness of users then the concept of denying use of a socket outlet by stating it should only be used for specific equipment is quite sensible.

If we took say a small workshop that had a number of sockets for "general use" by users then would an RCD be resonable (given some knowledge of the benefits)

Hower would it be reasonable to include RCD protection on a single socket behind say a piller drill and marked "Drill" - or for a socket at high level in the space Iie not readily accessible to users) intended only for use by someone plugging in a bit of environmental monitoring equipment (infrequently)

I supect this is about the industry trying to find a simple "default" position - which is a bit at odds with a collaborative risk assessment - but thats what we have.

In the absense of an RA then the default is RCD protection (as it is in the pre amendment version) - a designer or inspector may chose to take ownership and responsibility for the RA - but might be considered foolish for doing so - noting that the duty already exists for the designer under the CDM regs

It suggests that the designer or inspector asks for consultation, explains the issues and requests from the client the resultant RA - if that's not forthcoming, then the designer or inspector acts accordingly - by specification or by Coding

What is the reason for using the RCD in the first place if they are allowing you to omit it by virue of a label? Humph again


Because all of life is risk and some risks are bigger than others ?


Regards

OMS

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Let the wind blow you, across a big floor.
 07 February 2015 10:55 AM
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spinlondon

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Wasn't aware that anyone had been making such claims?
Would be surprised if anyone did.
I would have thought it quite obvious that it will be the designer who will be responsible for ensuring such documentation is in place.
As for who specifically conducts and produces the RA, will be something for the designer and the client to discuss.
It may be possible that an RA simply based on the Statutory requirements found in the EAWR and HASW may be acceptable?
However that would be for the designer to decide.
 07 February 2015 11:04 AM
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OMS

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That's about the size of it Spin - inspectors need to read the initial design information (or act as designers if the installation predates AMD 3)

I guess the subtle point is that the designer (or inspector) doesn't conduct the RA - they just need to check there is one in place (or go to default mode of RCD's on all sockets if they can't be ***** or if the client isn't known (say a spec office block))

Regards

OMS

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Let the wind blow you, across a big floor.
 07 February 2015 11:09 AM
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spinlondon

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I'm wondering how this requirement will apply to Electrac type systems and moving floor sockets in existing installations?
 07 February 2015 12:01 PM
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OMS

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Depends on the existing configuration I guess - as a minimum, it's conceivable that any new floor box might need to contain an integral RCD or RCD sockets - but any risk assessment would have to conclude that they all need doing or none need doing I suspect - which opens up the problem of putting RCD's on busbars with a large number of outlets (leakage tripping) or of swapping out all the floor boxes needlessly (or potentially so)

Regards

OMS

-------------------------
Let the wind blow you, across a big floor.
 07 February 2015 12:02 PM
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phantom9

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But, RCDs are only an added safety feature anyway. They have made TT systems safer and accidental penetration by nails and screws in to cables safer, using equipment outdoors safer. So I don't see why the labeling of a socket outlet makes it any safer by leaving off the RCD? The circuit may still be vulnerable to being damaged by nails/screws, cable may be less than 50mm deep in the building fabric. The predominant reason for using an RCD is to limit shock current from earth faults. By omitting one we still have the overcurrent and short circuit protection afforded by the fuse/mcb. How can anyone apply risk assessment to that scenario. Electricians struggle as it is so how can a customer or client make a reasonable assessment of whether to omit an RCD from a circuit or not? There appears to be too many laws now with contradicting influence and the net result is do it regardless because risk assessment is too hard to quantify. That's my take on it. What IS an RCD used for anyway?
 07 February 2015 12:23 PM
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OMS

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Originally posted by: phantom9

But, RCDs are only an added safety feature anyway. They have made TT systems safer and accidental penetration by nails and screws in to cables safer, using equipment outdoors safer.

Indeed

So I don't see why the labeling of a socket outlet makes it any safer by leaving off the RCD?

The reg is addressing the "use" of the socket

The circuit may still be vulnerable to being damaged by nails/screws, cable may be less than 50mm deep in the building fabric.

Covered by different regulation groups - the installation may be in metallic conduit (for example) but the sockets still need RCD protection to mitigate against carelessness of users

The predominant reason for using an RCD is to limit shock current from earth faults.

Not true - the RCD doesn't limit current - it only reduces time of exposure - it does react to lower values of current, but can't reduce them


By omitting one we still have the overcurrent and short circuit protection afforded by the fuse/mcb.

For typically 400ms disconnection

How can anyone apply risk assessment to that scenario.

An RCD would reduce that to 40ms - the risk is far greater from the apiance and cord being misused than from the fixed wiring


Electricians struggle as it is so how can a customer or client make a reasonable assessment of whether to omit an RCD from a circuit or not?

Some electricians might "struggle" - not all people using the "regs" are electricians however - nor all all clients incapable of making the required assessment (and probably in cojunction with thier appointed technical advisors)

There appears to be too many laws now with contradicting influence and the net result is do it regardless because risk assessment is too hard to quantify.

Not really - the situation is quite simple - BS 7671 defaults to a position of protecting users of socket outlets of less than 20A capacity by means of additional protection afforded by a 30mA non delayed RCD

That's my take on it. What IS an RCD used for anyway?

In this case, the RCD offers "additional protection" to users due to thier carelessness



Regards

OMS

-------------------------
Let the wind blow you, across a big floor.
 07 February 2015 02:46 PM
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IronFreely

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The point is there must be a risk assessment, doesn't matter who writes it so long as you know there is one, ideally all parties involved have proof of reading, which is why I have always emailed risk assessments with a read/receipt request and I have in my T's and C's that read requests must be replied to.
As it is the installer/tester's responsibility to adhere and inform responsible persons if the requirements of BS7671 then it's not a far stretch to suggest the responsibility of insuring the presence of a relevant risk assessment also resides with the installer/tester...
It's not like a risk assessment for a fixed item is going to be pages and pages... I recently wrote my own risk assessment when installing some 50 socket outlets to an IT room, as it was mostly computers going in it was fair to account for significant functional leakage. Risk assessment was a simple table showing the risk i.e electric shock, the likelyhood i.e low, the severity of potential incident i.e high/severe injury/death, control measures included all cables were run in visible routes i.e in conduit on the surface of the wall, no uncapped drinks should be allowed in the room, visual inspections to be carried out by a responsible person every three months, only IT equipment to be used on the relevant circuit with warning labels on each outlet, additional outlets with RCD protection installed for non IT purposes.

I'm not saying I like these requirements but it took a whole 2 minutes to write the risk assessment a further minute to explain it to the client and care taker, get them both to pop their signature at the bottom next to mine and five minutes to print the labels on my handy label maker, what I'm saying is it wasn't much of a stretch to comply and the clients had no idea before I presented them with the risk assessment - so I saw it as my responsibility to make sure it was taken care of and cost me all of ten minutes. No fuss.

Edit. I also agree that just because I've stuck a label on doesn't mean people can't go plugging in a toaster (although unlikely in an IT room) the risk assessment has empowered the care taker to inforce this procedure and he signed the risk assessment he is likely to get quite high and mighty about ensuring no one Is breaking the rules (we all know how care takers can be, hell I've been the repsponsible person before, jingling my keys, programming the alarm in a way that insured my continued employment and setting my passwords and all)

Edited: 07 February 2015 at 03:05 PM by IronFreely
 07 February 2015 02:58 PM
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OMS

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Mmmm - I think the point is that the RA isn't yours to undertake - as the designer you only need to know the documented outcome of the RA - not to undertake it

Regards

OMS

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Let the wind blow you, across a big floor.
 07 February 2015 03:17 PM
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IronFreely

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Originally posted by: OMS

Mmmm - I think the point is that the RA isn't yours to undertake - as the designer you only need to know the documented outcome of the RA - not to undertake it



Regards



OMS

Sure, but as we're the ones with the BYB we're the ones who know there should be a risk assessment, our clients on the other hand just say to themselves "I fancy some o them socket thingies to make computer things happen". Then we step in with our knowledge of earth leakage and say "hey we need a risk assessment here as we'll need to omit the requirement for an RCD as the functional leakage for all those computermebobs are going to cause nuisance tripping" then the client is going to say "what's an Ahrrr seeee deeee?"
So realistically who has the technical knowledge and expertise needed to compile a risk assessment fit for purpose, you guessed it - he who holds the big yellow book of words.
What I'm saying is we're suposed to be the experts here, so use you're expertise to ensure all the paperwork is in order and the responsible people you leave behind are properly informed and empowered to act apon that risk assessment.
You may of course be lucky enough to work on sites where people are aware of the purpose of and risks of omitting RCDs and indeed of the relevant control measures to reduce those risks so they can write the assessment, but in reality again it's likely to be the guy with the city and guilds who actually understands what's involved.
 07 February 2015 03:23 PM
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John Peckham

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As stated by my learned friend above the default position is sockets up to 20A are required to be 30mA RCD protected.

There is no exception for sockets up to 32A that could be used to supply portable equipment outside.

There is an exception for sockets up to 20A if they are designated for a particular purpose and labelled. No RA required.

There is also an exception for 20A sockets inside if there is a written risk assessment saying they are not required. The wise council are saying the designer should get the RA from the client at the design stage. There is a box to be ticked on the new EIC confirming that the RA is attached to the EIC.


The omission of a safety device, in this case a 30mA RCD, is a big step to take as it is there to protect the public from a fatal shock. I am saying that the designer should not carry out the RA but leave that to the client. The designer may want to give the client a menu of options and pros and cons of RCD protection but let the client make thge decision and let them sign the RA. A bit like saying the a client for a new ship that lifeboats are not required. If a designer was thinking about producing and signing an RA hey might want to get written consent for this activity from their insurers to confirm they have indemnity from the ongoing risks.

I am going to be even bolder and say I don't think an RA saying 30mA RCD protection should ever be required. I say this for the following reasons.

1. Consideration for the omission of RCD protection is carried out at the design stage.

2. The designer has common law and statutory duties to design a safe installation.

3. The problem of unwanted RCD tripping can be designed out at the design stage as required in 314.1 and 531.2.4. Having more circuits with less kit connected. Or an unprotected circuit with RCD sockets fitted.

4. Critical pieces of kit can be supplied via a fused connection unit. No RA required.

5. Critical pieces of equipment can be supplied from a labelled designated socket ( no RA required for the application of this exception. For a bit of a belt and braces safety for the critical socket use one with a special shaped earth pin which are readily available so Mrs Miggins the cleaner cannot unplug the critical equipment and plug in her Henry.

6. The RA exception does not apply to domestic premises.


Can some one think of a circumstance where the application of good design, and applying 1-6 above, would require a socket not to be 30mA RCD protected and be supported by an RA?

PS Iron freely why did you not opt for the labelled socket exception for your IT sockets? Why did you not consider using sockets with the non-standard earth pins? You labelled the sockets with your label gun so why the RA?

-------------------------
John Peckham

http://www.astutetechnicalservices.co.uk/

Edited: 07 February 2015 at 03:43 PM by John Peckham
 07 February 2015 03:42 PM
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OMS

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Originally posted by: IronFreely

Originally posted by: OMS

Mmmm - I think the point is that the RA isn't yours to undertake - as the designer you only need to know the documented outcome of the RA - not to undertake it

Regards

OMS


Sure, but as we're the ones with the BYB we're the ones who know there should be a risk assessment, our clients on the other hand just say to themselves "I fancy some o them socket thingies to make computer things happen".

Indeed - but the fact they fancy some sockets makes them a duty holder

Then we step in with our knowledge of earth leakage and say "hey we need a risk assessment here as we'll need to omit the requirement for an RCD as the functional leakage for all those computermebobs are going to cause nuisance tripping" then the client is going to say "what's an Ahrrr seeee deeee?"

This has little to do with earth leakage - that's a design problem. This is about protecting casual users of socket outlets from the attendant risks - usually through thier own carelesness

So realistically who has the technical knowledge and expertise needed to compile a risk assessment fit for purpose, you guessed it - he who holds the big yellow book of words.

Nonsense - would you take the same approach if you had a copy of BS 5839 - would you write the fire risk assessment ?

What I'm saying is we're suposed to be the experts here, so use you're expertise to ensure all the paperwork is in order and the responsible people you leave behind are properly informed and empowered to act apon that risk assessment.

Me, I'd never call myself an expert under any circumstances unless I was in court acting as an expert witness.

That said, there is no problem offering the client technical advise, but be very careful of assuming duties that aren't yours - that way there be dragons.

Lets take an incident in your example where there is a fatality - the client is going to wave his bit of paper and say "It was him - he told me not to put in a recognised safety device" - then there'll be some smart Alec like me in a coyrtroom asking what the hell you were thinking of by removing a widely recognised safety device despiye you being an expert an' all even though the bumper fun book tells you that the default position is they should be there


You may of course be lucky enough to work on sites where people are aware of the purpose of and risks of omitting RCDs and indeed of the relevant control measures to reduce those risks so they can write the assessment, but in reality again it's likely to be the guy with the city and guilds who actually understands what's involved.

So offer advice as a competent person - just don't write the risk assessment - you can even tell them what to say - but I most certainly won't be putting my name to it.

If I were you, I'd do a check on my PII cover and then start moving your assets into Memsahib's name



Regards

OMS

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Let the wind blow you, across a big floor.
 07 February 2015 03:48 PM
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leckie

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So, as an example, you are to inspect an existing commercial property, say a 30 year old warehouse with offices. Say there are 10 x 13a sockets scattered around the warehouse, so for fixed equipment, drinks machine, etc. The office has has a ring-main for 13a sockets, let's say six pc workstations and a few general use twin sockets.

So we can assume that the sockets to both areas get general use by cleaners, contractors, staff, etc.

Let's say there is an old PIR that mentions no RCD to sockets, but that the building is under the control of instructed persons. Let say there are no RA's and nobody you talk to is aware of any special instructions.

What would be a reasonable approach now, and how does it change with AMD3?

I have never been very happy with just saying the installation is under the supervision of skilled or competent people and therefore the rcd's can be omitted. I have usually taken the view of issuing a C3 and have been advising that a risk assessment should be carried out. I assume that with AMD3 it will be a C2 if no RA is available.

Edited: 07 February 2015 at 03:54 PM by leckie
 07 February 2015 03:54 PM
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geoffsd

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Originally posted by: Zs
An exception to (i) is permitted:
(a) where, other than for an installation in a dwelling, a documented risk assessment determines that the RCD protection is not necessary, OR
(b) for a specific labelled or otherwise suitably identified socket outlet provided for connection of a particular item of equipment.


Does not the OR make quite a difference to the above discussion?
 07 February 2015 03:59 PM
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leckie

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And what happens if you inspect a building and they have a RA but you read it and think it's carp? do you say ok that's fine or, no that's not good enough so it's a C3 or, sorry it's still a C2?
 07 February 2015 04:09 PM
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John Peckham

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Leckie

The skilled or competent person exception has gone out of AMD 3. Indeed competent person has been replaced in the Part 2 Definitions with Skilled Person (Electrically). How this competent or instructed person could have exercised some magical power over the installation we must confine to the dustbin of history. The competent person magic power over sockets and cables in metal stud work has been removed from AMD 3.

We have been talking about new installation above and the commission of RCDs and risk assessments.

If you are carrying out a periodic inspection and test of an existing installation then if it is not a labelled socket for designated piece of equipment and there is no RA attached to the original EIC (early days for a periodic on an installation with an RA) then it is a C3 defect. You are recommending improvement, the client can ignore your recommendation if they so wish but be it upon their heads if there was an accident that could have been prevented by implementing your recommendation. If you don't record the absence of RCD protection and there was an accident the client would no doubt point the finger at you and say" if he had only have told me a should have fitted RCD protection I would have done".


If it is a socket outside or could be used outside with no 30mA RCD protection then it is a C2.

Your report your signature you may be held accountable some time in the future so be risk averse and rectum protectum. if it does not compliant with the current regulations record and code it.

-------------------------
John Peckham

http://www.astutetechnicalservices.co.uk/
IET » Wiring and the regulations » 411.3.3

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