To work live or not??

[bs123]

Hi

I was wondering if anybody can shed some light on this.
I am working on a job in a hospital and they want to run in some
new circuits for tv's in all the wards. They have an excisting
3 phase board but want to install consumer units next to
the 3 phase board to tap off from to the new consumer units.
I have been told that this have to be done live as they can
not isolate the main board for obvious reasons. Needless to
say i am not to keen on this idea. When i was doing my 2360
i was told to never work live as there is no reason to take
the risk and that a supply can always be isolated if need be.
Also can i refuse to do the job under Healt&Safety laws?

Many Thanks for your advise.

 

[Adam W]

When I was at college they presented the idea that if the circuits can't be isolated under planned circumstances, you certainly shouldn't increase the risk of them tripping under unplanned circumstances by working live.

By the sound of it you'll only need to isolate the main board to make the final connection, so should only be for 30 mins or so.

 

[Sparky Ninja]

Carrying out any work whilst 'live' will be against the electricity at work regs and so a shut down should and could be arranged.

 

[ghost]

In today's world of health and safety, I would say no. You are working in a hospital, therefore a risk of tripping circuits that are essential. I'm sure the hospital would want a risk assessment carrying out first.
On the other hand, if you get chucked across the room, you are in the right place. Your choice.

 

[davelerave]

i work live quite a bit

as already said you might trip an essential circuit /cause a SC anyway

- i would plan an outage in this case as it's a hospital

 

[gawain]

defiantly don't work live in any circumstances your putting yourself in unnecessary risk.

 

[Spudnik]

Dont hospitals have UPS for vital equipment anyway?

 

[DiscoDave]

I've tried typing this so it sounds right, but sod it NO, don't work live, you shouldn't be expected to work live and you most definitely don't have to!

 

[mogga]

UPS Supplies the DB but if mcbs are turned off then no supply

IMO the hospital engineering team wouldnt allow you to work live and should plan a shutdown for you although they may ba awkward due to them not doing the job

 

[gunner]

do not work live.it is not your problem

 

[pennywise]

So all your doing is adding consumer unit supplies from an existing TP-N board with spare ways.

 

[WayneL]

I would have thought a risk assessment, appropriate precautions and PPE, and connect up.

The DNOs do it every day, so why should it be any different for us??

 

[Scud]

I would have thought a risk assessment, appropriate precautions and PPE, and connect up.

The DNOs do it every day, so why should it be any different for us??

No they don't. The basic principle is never work live. The EAWR says that.

 

[WayneL]

No they don't. The basic principle is never work live. The EAWR says that.

Think what you like, but a few weeks back I was talking to a Scottish Power spark down a hole in the pavement.

He was repairing a damaged piece of cable - it was only 230V to earth - just your normal street ring-main....but he was working Live!

He had on 1000V insulated gloves and was joining a new section of cable to supply the street - he could hardly switch it of at the sub-station

Also, have you not heard of cable jointers - 11 KV cable jointing - working live!

As they do when working on Pilons - they're hardly going to switch the national grid off.

Sometimes you have to work live - The EAWR doesn't say you can't, it says you shouldn't:

Work on or near live conductors


14. No person shall be engaged in any work activity on or so near any live conductor (other than one suitably covered with insulating material so as to prevent danger) that danger may arise unless-

• (a) it is unreasonable in all the circumstances for it to be dead; and

• (b) it is reasonable in all the circumstances for him to be at work on or near it while it is live; and

• (c) suitable precautions (including where necessary the provision of suitable protective equipment) are taken to prevent injury.

• In other words, if the above criteria are met, then you can work live

 

[UNG]

In the original post it does not make it clear whether the three phase DB has exposed busbars or not it just refers to isolating it without giving any reason as to why this DB should be isolated other than it is live

Over the years I have connected to many three phase DB's while they were live but the hazards where identified and the risks assessed if there were any exposed live busbars or conductors

Unfortunately it appears to be easier to teach and advocate total isolation as the safe method of working these days on all equipment even if there are no exposed conductors to touch rather than the methods to be used when it may be acceptable to work on live DB's

WayneL's post shows that even the HSE admit that working near live conductors may be necessary.

 

[benji]

As in previous threads it,s down to risk assesments and method statements and don,t forget it,s your engineer that you work for who should write the risk/method statements and only if you agree with the statements you will sign them and procede to do the task.The chances of isolating a db in a hospital are nil ,and even with a very experienced electrician just taking the cover off say a 24w tp dis board it,s easy to trip a breaker.If youve got to fit a new mcb into said board you should be ok with a single pole but triple poles are a nightmare due to the metal clips that hold the breakers together.
But if everything is in place and everybody knows what they are doing and everybody is aware of what is happening (including the effected wards ) ect. it should be well within the scope of a experienced electrician to complete the task.

yours benji

 

[jase]

on Quite a lot of boards you cant take the cover off without turning it off, so just fitting mcbs for the new consumer unit would not happen unless the board was switched off even for a minute

 

[Scud]

Think what you like, but a few weeks back I was talking to a Scottish Power spark down a hole in the pavement.

He was repairing a damaged piece of cable - it was only 230V to earth - just your normal street ring-main....but he was working Live!

He had on 1000V insulated gloves and was joining a new section of cable to supply the street - he could hardly switch it of at the sub-station

Also, have you not heard of cable jointers - 11 KV cable jointing - working live!

As they do when working on Pilons - they're hardly going to switch the national grid off.

Sometimes you have to work live - The EAWR doesn't say you can't, it says you shouldn't:

• In other words, if the above criteria are met, then you can work live

Firstly, the jointer was wearing Class 1, 7500V gloves. SP doesn't issue 1000V gloves to anyone. Secondly, as you rightly say, the EAWR does make provision for working live. However, inconvenience alone can never be a criterion for live working. Another mistake you made is that linesmen on pylons do not work live-ever. That is an establsihed fact. There are specialists who work live on HV lines by being dropped onto lines from a helicopter, wearing Farday cage suits. There are also 'rubber glove' temas who work from insulated hoists on up to 11kV only. None of this is relevant to the issue at hand. In the hospital scenarion, not only would no court in the land entertain a claim by someone who says they were todl to work live and got injured as a result, they themsleves would be liable to prosecution under Section 7 of the Health and Safety at Work Act, having breached the EAWR, Regulation 14.

No person shall be engaged in any work activity on or so near any live conductor (othet than one suitably covered with insulating material so as to prevent danger) that danger may arise unless-

(a) it is unreasonable in all the circumstances for it to be dead; and

(b) it is unreasonable in all the circumstances for him to be at work on or near whilst it is live; and

(c) suitable precautions (including where necessary the provision of suitable protective equipment) are taken to prevent injury.

Note that in (a) the phrase 'in all the circumstances' is used.

Among other things, I teach the EAWR, and I can assure you that the circumstances that the OP talks of would never be accepted as criteria for live working, and anyone who advises him otherwise is being extremely naive, not to mention irresponsible. However, if the OP is still not sure, and I can see no reaosn why you would take the word of a perfect stranger like me, I would suggest a phone call to the HSE for advice.

 

[WayneL]

Firstly, the jointer was wearing Class 1, 7500V gloves. SP doesn't issue 1000V gloves to anyone.

The chap I was talking to was working on a 230V domestic supply cable and was wearing Class 0 1000V gloves:

INSULATING GLOVES, INSULATING BOOTS, ELECTRICAL SAFETY GLOVES, HV GLOVES, LINESMANS BOOTS

However, inconvenience alone can never be a criterion for live working.

The hospital scenario presented would hardly be labelled 'inconvenience' - they could have equipment that cannot be turned off.....life support, for instance.

Another mistake you made is that linesmen on pylons do not work live-ever. That is an establsihed fact. There are specialists who work live on HV lines by being dropped onto lines from a helicopter, wearing Farday cage suits. There are also 'rubber glove' temas who work from insulated hoists on up to 11kV only.

The conductors are either live or they're not - regardless of how they tackle the job or what equipment they use.

No person shall be engaged in any work activity on or so near any live conductor (othet than one suitably covered with insulating material so as to prevent danger) that danger may arise unless-

(a) it is unreasonable in all the circumstances for it to be dead; and

(b) it is unreasonable in all the circumstances for him to be at work on or near whilst it is live; and

(c) suitable precautions (including where necessary the provision of suitable protective equipment) are taken to prevent injury.

Note that in (a) the phrase 'in all the circumstances' is used.

I have already quoted the regulation above.

Bottom line is, the EAWR do not state that you must not work live - they are saying that if it is unreasonable not to, then all necessary precautions must be taken - just like in Inspection and Testing....I'd like to see you measure Ze or PFC without working on live conductors

 

[Scud]

"The chap I was talking to was working on a 230V domestic supply cable and was wearing Class 0 1000V gloves:"

Then he was working contrary to company regulations. ScottishPower do not approve the use of Class 0 gloves under any circumstances. We have no cables buried under streets which are single phase. A jointer may work live under the auspices of SP's Live Working Manual, but only in certain circumstances. Of course, they will never expose two phases at once,nor will they expose a line and neutral conductor at the same time, ergo, they only ever work on either a single line conductor or a neutral conductor. The only PPE approved for use when working on or near live conductors is Class 1 gloves, full face visor and flame retardant overalls of the approved pattern, complete with full chin flap. I'm not guessing at this, as I said, I teach this stuff to SP operatives and contractors requiring authorisation on the SP network.

"The hospital scenario presented would hardly be labelled 'inconvenience' - they could have equipment that cannot be turned off.....life support, for instance."

All hospitals are required by law to have backup systems cap[able of maintaining vital services for a protracted period in the evnt of a power cut. I'm afraid that one doesn't bear close examination.

"The conductors are either live or they're not - regardless of how they tackle the job or what equipment they use."

Agreed. However, you stated that linesmen on pylons work live. They do not. Ever. You can't climb a pylon and gain access to HV cables (pylons carry a minimum 132kV) without killing yourself. All HV work above 11kV is carried out dead in SP's area.


"Bottom line is, the EAWR do not state that you must not work live - they are saying that if it is unreasonable not to, then all necessary precautions must be taken - just like in Inspection and Testing....I'd like to see you measure Ze or PFC without working on live conductors "

I will concede your point in this case, although I maintain that the circumstances presented to us by the OP would not hold up in a court of law as 'reasonable'. It is the responsibility of the hospital under the HASAW to protect the safety of its workers and of any contractors working on their premises.