wrote in message
...
On Tuesday, 23 June 2015 22:58:13 UTC+1, ARW wrote:
nt wrote in message
...
On Monday, 22 June 2015 21:51:09 UTC+1, ARW wrote:
nt wrote in message
...
On Monday, 22 June 2015 20:40:40 UTC+1, ARW wrote:
nt wrote in message
...
On Sunday, 21 June 2015 23:20:25 UTC+1, Jim x321x wrote:
My house was built and wired in the 1980s and has an old-style
fuse
box.


Is there really a significant
increase in electrical safety with the modern RCD units?

There are 20 something deaths from shock a year, mostly due to
people
doing idiotic things. RCDs reduce the risk. This is a long way
down
the
list of Risky Things in Life, so is the oposite of a priority.


So what what would you prioritize?

Look at the top 10 killers.
http://www.cdc.gov/nchs/fastats/lead...s-of-death.htm

The top 2 are heart disease & cancer. They kill half the population.
Expert concensus is half these deaths are readily avoidable by
healthier
eating, not smoking & some exercise. These are the number 1
priorities.

A lifesyle choice is not relevant to diy or general risks in the house.

Risks and the cost of avoiding them are 100% relevant to risks and the
cost of avoiding them


I do not consider telling a fat ******* to eat less less food to be DIY
related.

Fitting a lock on a fridge is DIY related.

So what. A DIY safety improvement is only worth doing if its not way down
the list of what one can usefully do. RCDs have their upside, but at 20
something deaths versus over 100,000 a year they're just not the priority.
Eat healthily, learn advanced driving, treat infections promptly &
vigilantly, take proper precautions with power tools and so on. If all those
plus dozens of others are done, then an RCD becomes worthwhile.

Funny how so many think electricity & gas a big risk, when really the most
dangerous things we do are food shopping & smoking.



What is not so funny is how many people do not realise how dangerous
electrcity is.

It takes 20 to 30 years of smoking or shoveling chips down a big fat gob to
cause the damage. If they cannot see what is coming then it is their
problem - the NHS spend a fortune on preventative medicine and yet people
still live unhealthy lifestyles.

Electricity is unseen and kills in less than a second and may not be the
fault of the person that is killed. The IET have decided that RCD protection
is the future. It's not expensive and it saves lives - so much so that there
are thousands of people who did not receive the smallest of shocks when the
RCD operated saving them from becoming a minor statistic.




--
Adam

John Rumm wrote:
On 22/06/2015 09:56, Jim x321x wrote:
John Rumm wrote in
:

with the existing setup, and I rarely get any inexplicable tripping
of the circuit breakers. As far as I am aware, the old fuse boxes
(even when fuses contained fuse wire) did what they were designed to
do, with no problems.

They did what they were supposed to - and will still do so. The main
thing your current setup lacks is RCD protection.


Thanks to all for the excellently helpful advice.

If I added an RCD covering the entire house (without replacing the existing
fuse box which is already fitted with MCBs, would that constitute a change
to the wiring and thus require building control notification?

Firstly you don't want a single RCD covering the whole house - that is a
practice that was common during the 15th edition, but is deprecated now
since it offers no "discrimination" in the event of a fault (i.e. the
fault will take out the supply to the whole house, not just the circuit
causing the problem). So many circuits on one RCD are also more prone to
nuisance tripping in the first place.

Changing a CU is "notifiable", although if done right no one is going to
whinge if you don't.

Would doing this significantly improve the house's safety rating in the
eyes of, say, a house-purchaser's surveyor?

Only if the purchaser is sufficiently clued up. You may find an older CU
etc would be commented on during a survey, but only in as much as the
surveyor might comment that you could get an electrical report if concerned.

So if your only reason for the change is to make the house more saleable,
I would not bother. If however you are planning to carry on living there,
then its worth it (IMHO) for other reasons.


Just sold my house and survey recommended an electrical report, changing
the old fused CU was the result... (There was a hairline crack on the unit
as well, which didn't help)

"cupra" wrote in message
...
John Rumm wrote:
On 22/06/2015 09:56, Jim x321x wrote:
John Rumm wrote in
:

with the existing setup, and I rarely get any inexplicable tripping
of the circuit breakers. As far as I am aware, the old fuse boxes
(even when fuses contained fuse wire) did what they were designed to
do, with no problems.

They did what they were supposed to - and will still do so. The main
thing your current setup lacks is RCD protection.


Thanks to all for the excellently helpful advice.

If I added an RCD covering the entire house (without replacing the
existing
fuse box which is already fitted with MCBs, would that constitute a
change
to the wiring and thus require building control notification?

Firstly you don't want a single RCD covering the whole house - that is a
practice that was common during the 15th edition, but is deprecated now
since it offers no "discrimination" in the event of a fault (i.e. the
fault will take out the supply to the whole house, not just the circuit
causing the problem). So many circuits on one RCD are also more prone to
nuisance tripping in the first place.

Changing a CU is "notifiable", although if done right no one is going to
whinge if you don't.

Would doing this significantly improve the house's safety rating in the
eyes of, say, a house-purchaser's surveyor?

Only if the purchaser is sufficiently clued up. You may find an older CU
etc would be commented on during a survey, but only in as much as the
surveyor might comment that you could get an electrical report if
concerned.

So if your only reason for the change is to make the house more saleable,
I would not bother. If however you are planning to carry on living there,
then its worth it (IMHO) for other reasons.


Just sold my house and survey recommended an electrical report, changing
the old fused CU was the result... (There was a hairline crack on the unit
as well, which didn't help)



--
Adam

What is not so funny is how many people do not realise how dangerous
electrcity is.

It takes 20 to 30 years of smoking or shoveling chips down a big fat gob to
cause the damage. If they cannot see what is coming then it is their
problem - the NHS spend a fortune on preventative medicine and yet people
still live unhealthy lifestyles.

Electricity is unseen and kills in less than a second and may not be the
fault of the person that is killed. The IET have decided that RCD protection
is the future. It's not expensive and it saves lives - so much so that there
are thousands of people who did not receive the smallest of shocks when the
RCD operated saving them from becoming a minor statistic.





I wish they were in common use around 35 years ago when I got "stuck"
across live to a less than correct earth on a metal handled drill;(...

Remember it to this day still, the pain and not being able to do anything
about it and that terror that this was going be my last day alive!

--
Tony Sayer

"Robin" wrote in message
...
John Rumm wrote:

Probably depends on the area of the country... I would have thought a
straight swap would start at £200 - £300.

I think that'd be v much the bottom of the range in London now the trade
has picked up again.



And then there are the "extras" like one place near here told they needed
*separate* main bonding for incoming gas and water. There was 10mm looped
continuously MET-water-gas but the nice man even showed them the picture
in his little book to prove they needed to be separate

The word "******" springs to mind.


--
Adam

On Wednesday, 24 June 2015 10:59:29 UTC+1, Jim x321x wrote:
Can someone tell me if I can get away with a 45A MCB for a 8.5kW shower
without endagering life and limb? The manual tells me to use a 40A one, but
I just happen to have a 45A one. I ask, because those things aren't cheap.


Probably, as you're not relying on the MCB for overload protection (as the load is fixed and unlikely to draw a higher than rated current), merely for short circuit in the event of fault.

What is the cable size an mounting method.?

Owain

wrote in
:

On Wednesday, 24 June 2015 10:59:29 UTC+1, Jim x321x wrote:
Can someone tell me if I can get away with a 45A MCB for a 8.5kW
shower without endagering life and limb? The manual tells me to use a
40A one, but I just happen to have a 45A one. I ask, because those
things aren't cheap.


Probably, as you're not relying on the MCB for overload protection (as
the load is fixed and unlikely to draw a higher than rated current),
merely for short circuit in the event of fault.

What is the cable size an mounting method.?

Owain



It's a 6mm^ T&E cable that is surface mounted all the way to the 8.5kW
shower. (about 4ft goes through surface-mounted conduit.

So, I could use the spare 45A MCB. I also have a spare 20A MCB which I
could swap with the upstairs ring-main's 32A MCB and use the 32A MCB for
the shower instead of the 45A one. Which would be the better option? (I
guess the upstairs ring main would be fine on a 20A MCB, since I don't run
any heating applicances upstairs and its only a 3-bed house.

Many thanks,

Jim

On Friday, 26 June 2015 09:12:55 UTC+1, Jim x321x wrote:
It's a 6mm^ T&E cable that is surface mounted all the way to the 8.5kW
shower. (about 4ft goes through surface-mounted conduit.

6mm clipped direct is ok for about 47A.

The only risk is that someone at a later date might see the 45A MCB and think it's okay to put a higher-rated shower on it without calculating for the 6mm cable size.

I'd leave the 45A MCB in and label accordingly.

Owain

wrote in
:

On Friday, 26 June 2015 09:12:55 UTC+1, Jim x321x wrote:
It's a 6mm^ T&E cable that is surface mounted all the way to the
8.5kW shower. (about 4ft goes through surface-mounted conduit.

6mm clipped direct is ok for about 47A.

The only risk is that someone at a later date might see the 45A MCB
and think it's okay to put a higher-rated shower on it without
calculating for the 6mm cable size.

I'd leave the 45A MCB in and label accordingly.

Owain


Much appreciated,

Jim

On 23/06/2015 22:52, wrote:
On Tuesday, 23 June 2015 17:20:21 UTC+1, John Rumm wrote:
On 22/06/2015 21:51, ARW wrote:
nt wrote in message
...
On Monday, 22 June 2015 20:40:40 UTC+1, ARW wrote:
nt wrote in message
...
On Sunday, 21 June 2015 23:20:25 UTC+1, Jim x321x wrote:
My house was built and wired in the 1980s and has an old-style
fuse box.


Is there really a significant
increase in electrical safety with the modern RCD units?

There are 20 something deaths from shock a year, mostly due to people
doing idiotic things. RCDs reduce the risk. This is a long way down
the
list of Risky Things in Life, so is the oposite of a priority.


So what what would you prioritize?

Look at the top 10 killers.
http://www.cdc.gov/nchs/fastats/lead...s-of-death.htm

The top 2 are heart disease & cancer. They kill half the population.
Expert concensus is half these deaths are readily avoidable by
healthier eating, not smoking & some exercise. These are the number 1
priorities.

A lifesyle choice is not relevant to diy or general risks in the house.

Not only that, as had been pointed out at various times, one insures
against losses that one can't otherwise replace. I would include wife
and children in that category, so a one off premium of a couple of
hundred for smoke alarms and RCDs sounds like a very worthwhile investment.

2 different issues lumped together,

Smoke alarms and RCDs are different - however the risks associated with
not having either are comparable (although injury from fires per years
are far fewer than from electric shock). I seem to recall someone round
here was very fond of plastering domestic fire safety stats into every
wiki article given the chance. Why the double standards?

and a non sequitur.

Explain

Maybe some of us just aren't into risk assessment.

You think... I wonder who?


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 24/06/2015 10:59, Jim x321x wrote:
Harry Bloomfield wrote in
:


Every 10 minutes to an hour the RCD would trip out, leaving everyone
in complete darkness down there. Try explaining to a site agaent that
the risk of electrocution on a 55v to ground system is considerably
less than the risk of someone being seriously injured, with it
tripping so regularly leaving everyone in such circumstances in
complete darkness, feeling for the ladder to climb out.


Sounds like a classic case of the 'Peter Pricipal' at play!

Can someone tell me if I can get away with a 45A MCB for a 8.5kW shower
without endagering life and limb? The manual tells me to use a 40A one, but
I just happen to have a 45A one. I ask, because those things aren't cheap.

Yes... the purpose of the MCB is really to give adequate fault
protection to the cable. You can use the adiabatic check to make sure
you meet that objective.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 26/06/2015 09:12, Jim x321x wrote:
wrote in
:

On Wednesday, 24 June 2015 10:59:29 UTC+1, Jim x321x wrote:
Can someone tell me if I can get away with a 45A MCB for a 8.5kW
shower without endagering life and limb? The manual tells me to use a
40A one, but I just happen to have a 45A one. I ask, because those
things aren't cheap.


Probably, as you're not relying on the MCB for overload protection (as
the load is fixed and unlikely to draw a higher than rated current),
merely for short circuit in the event of fault.

What is the cable size an mounting method.?

Owain



It's a 6mm^ T&E cable that is surface mounted all the way to the 8.5kW
shower. (about 4ft goes through surface-mounted conduit.

Most of that is Method C, but the section of trunking means you need to
treat it all as Method B. That gives the cable a continuous rating of 38A.

Your design current is 8500 / 230 = 37A, so you are ok there (just).

Let's assume you are TN-C-S, and we will take the default 0.35 ohms as
the supply & EL impedance.

The cable round trip resistance will be 6.16 mOhms / metre.

Did you say the total run was 12m? If so that gives a total round trip
(by calculation - may be lower by measurement) 0.35 + 12 x 0.00616 =
0.42 ohms.

That gives a prospective fault current of 230 / 0.42 = 542A. The 0.1ms
trip threshold for a B type MCB is 5x In, or 5 x 45 = 225A in this case.
So we are safely into the magnetic or "instant" response part of the
curve for the MCB.

For piece of mind, treat the design as a non RCD one (even though a RCD
is required for other reasons), and ensure the fault withstand
capability of the cable is ok with that (nice to know the able won't
fail if the RCD does):

s = sqrt( 542^2 x 0.1 ) / 115 = 1.5mm^2 of CPC required (you have
2.5mm^2 of CPC in a 6mm^ T&E, so that is ok as well).

(where 115 is the k factor for PVC clad cable)

So based on a few assumptions - you are good to go. You will have no
overload protection for the cable, but that is not required in this case
due to the nature of the load.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Friday, 26 June 2015 16:23:39 UTC+1, John Rumm wrote:
On 23/06/2015 22:52, tn wrote:
On Tuesday, 23 June 2015 17:20:21 UTC+1, John Rumm wrote:
On 22/06/2015 21:51, ARW wrote:
nt wrote in message
...
On Monday, 22 June 2015 20:40:40 UTC+1, ARW wrote:
nt wrote in message
...
On Sunday, 21 June 2015 23:20:25 UTC+1, Jim x321x wrote:
My house was built and wired in the 1980s and has an old-style
fuse box.


Is there really a significant
increase in electrical safety with the modern RCD units?

There are 20 something deaths from shock a year, mostly due to people
doing idiotic things. RCDs reduce the risk. This is a long way down
the
list of Risky Things in Life, so is the oposite of a priority.


So what what would you prioritize?

Look at the top 10 killers.
http://www.cdc.gov/nchs/fastats/lead...s-of-death.htm

The top 2 are heart disease & cancer. They kill half the population.
Expert concensus is half these deaths are readily avoidable by
healthier eating, not smoking & some exercise. These are the number 1
priorities.

A lifesyle choice is not relevant to diy or general risks in the house.

Not only that, as had been pointed out at various times, one insures
against losses that one can't otherwise replace. I would include wife
and children in that category, so a one off premium of a couple of
hundred for smoke alarms and RCDs sounds like a very worthwhile investment.

2 different issues lumped together,

Smoke alarms and RCDs are different - however the risks associated with
not having either are comparable (although injury from fires per years
are far fewer than from electric shock).

200 something deaths a year in fires now, 20 something from shock

I seem to recall someone round
here was very fond of plastering domestic fire safety stats into every
wiki article given the chance. Why the double standards?

why the claim of double standards? how would stating the known facts possibly be that? Its not even worth answering.

and a non sequitur.

Explain

I already have. I've shown how I assessed whether RCDs were worth fitting. You simply did not address the necessary points in order to reach a reason based case on the question of whether its a good things to install your RCDs.

Maybe some of us just aren't into risk assessment.

You think... I wonder who?

I've offered a clear risk & cost asessment, plus placed it in the list of available risk reductions, thereby determining if its a priority or whether there are far bigger priorities. Yours has so far been an assessment of the risk followed by an illogical conclusion.

Unfortunately the approach you've shown is common today. It results in people spending on tiny risks and consequently neglecting the big ones. No-one has the resources to address all risks, so the sensible approach is to prioritise the ones we can reduce the most. That is evidently not RCDs, unless you've effectively tackled a fairly long list of others already.


NT

John Rumm wrote in
o.uk:

Subject: Do I need to update my house's fuse box?
From: John Rumm
Newsgroups: uk.d-i-y

On 26/06/2015 09:12, Jim x321x wrote:
wrote in
:

On Wednesday, 24 June 2015 10:59:29 UTC+1, Jim x321x wrote:
Can someone tell me if I can get away with a 45A MCB for a 8.5kW
shower without endagering life and limb? The manual tells me to use
a 40A one, but I just happen to have a 45A one. I ask, because
those things aren't cheap.


Probably, as you're not relying on the MCB for overload protection
(as the load is fixed and unlikely to draw a higher than rated
current), merely for short circuit in the event of fault.

What is the cable size an mounting method.?

Owain



It's a 6mm^ T&E cable that is surface mounted all the way to the
8.5kW shower. (about 4ft goes through surface-mounted conduit.

Most of that is Method C, but the section of trunking means you need
to treat it all as Method B. That gives the cable a continuous rating
of 38A.

Your design current is 8500 / 230 = 37A, so you are ok there (just).

Let's assume you are TN-C-S, and we will take the default 0.35 ohms as
the supply & EL impedance.

The cable round trip resistance will be 6.16 mOhms / metre.

Did you say the total run was 12m? If so that gives a total round trip
(by calculation - may be lower by measurement) 0.35 + 12 x 0.00616 =
0.42 ohms.

That gives a prospective fault current of 230 / 0.42 = 542A. The 0.1ms
trip threshold for a B type MCB is 5x In, or 5 x 45 = 225A in this
case. So we are safely into the magnetic or "instant" response part of
the curve for the MCB.

For piece of mind, treat the design as a non RCD one (even though a
RCD is required for other reasons), and ensure the fault withstand
capability of the cable is ok with that (nice to know the able won't
fail if the RCD does):

s = sqrt( 542^2 x 0.1 ) / 115 = 1.5mm^2 of CPC required (you have
2.5mm^2 of CPC in a 6mm^ T&E, so that is ok as well).

(where 115 is the k factor for PVC clad cable)

So based on a few assumptions - you are good to go. You will have no
overload protection for the cable, but that is not required in this
case due to the nature of the load.


Many thanks for the detailed reply. So what would be the ideal rating of
MCB to use? I just ordered a 40A one, because that's what the shower
manual recommends. The 45A one I had wasn't ideal because it wasn't a
Wylex one, and didn't fit without removing the base plate.

Jim

On Fri, 26 Jun 2015 11:54:47 -0700, tabbypurr wrote:

On Friday, 26 June 2015 16:23:39 UTC+1, John Rumm wrote:
On 23/06/2015 22:52, tn wrote:
On Tuesday, 23 June 2015 17:20:21 UTC+1, John Rumm wrote:
On 22/06/2015 21:51, ARW wrote:
nt wrote in message
...
On Monday, 22 June 2015 20:40:40 UTC+1, ARW wrote:
nt wrote in message
...
On Sunday, 21 June 2015 23:20:25 UTC+1, Jim x321x wrote:
My house was built and wired in the 1980s and has an old-style
fuse box.


Is there really a significant increase in electrical safety
with the modern RCD units?

There are 20 something deaths from shock a year, mostly due to
people doing idiotic things. RCDs reduce the risk. This is a
long way down
the
list of Risky Things in Life, so is the oposite of a priority.


So what what would you prioritize?

Look at the top 10 killers.
http://www.cdc.gov/nchs/fastats/lead...s-of-death.htm

The top 2 are heart disease & cancer. They kill half the
population. Expert concensus is half these deaths are readily
avoidable by healthier eating, not smoking & some exercise. These
are the number 1 priorities.

A lifesyle choice is not relevant to diy or general risks in the
house.

Not only that, as had been pointed out at various times, one insures
against losses that one can't otherwise replace. I would include
wife and children in that category, so a one off premium of a couple
of hundred for smoke alarms and RCDs sounds like a very worthwhile
investment.

2 different issues lumped together,

Smoke alarms and RCDs are different - however the risks associated with
not having either are comparable (although injury from fires per years
are far fewer than from electric shock).

200 something deaths a year in fires now, 20 something from shock

I seem to recall someone round here was very fond of plastering
domestic fire safety stats into every wiki article given the chance.
Why the double standards?

why the claim of double standards? how would stating the known facts
possibly be that? Its not even worth answering.

and a non sequitur.

Explain

I already have. I've shown how I assessed whether RCDs were worth
fitting. You simply did not address the necessary points in order to
reach a reason based case on the question of whether its a good things
to install your RCDs.

Maybe some of us just aren't into risk assessment.

You think... I wonder who?

I've offered a clear risk & cost asessment, plus placed it in the list
of available risk reductions, thereby determining if its a priority or
whether there are far bigger priorities. Yours has so far been an
assessment of the risk followed by an illogical conclusion.

Unfortunately the approach you've shown is common today. It results in
people spending on tiny risks and consequently neglecting the big ones.
No-one has the resources to address all risks, so the sensible approach
is to prioritise the ones we can reduce the most. That is evidently not
RCDs, unless you've effectively tackled a fairly long list of others
already.


In a nut shell, humanity's short sightedness when it comes to deciding
how we should spend effort and resources on tackling 'problems'. The
Green Party's obsession with wind turbine, solar voltaic and tidal
sources of energy is a classic case in point.

They regard these sources of Mother Nature's 'energy bounty' as being
'Low Tech' eco-friendly ways to solve the world population's energy
demands when they're anything but 'eco-friendly'.

They choose to ignore that other 'energy bounty' on offer from 'Mother
Nature', Nuclear Fission, on the basis that it requires ingenious high
tech methods of extraction involving, at the point of energy extraction,
highly dangerous radio active materials that have to be properly handled
and processed to reduce the risk to the environment at large by two or
three orders of magnitude compared to a conventional coal fired power
station of equivalent energy output.

Their thinking has been coloured by their experience of the earlier
nuclear powered station technologies driven by the needs of the cold war
demands to build up stocks of weapons' grade plutonium using power
stations sited in remote locations, seemingly to reduce the impact of a
Chernobyl like event on the population at large.

The plain fact is, it is now possible to upgrade existing coal fired
power stations to nuclear power, based on a Liquid Fueled Thorium Reactor
(LFTR) design that was first experimented with half a century ago as a
potential method of powering a USAF 'Always Aloft' Bomber Fleet.

Only the American Military had a big enough priority and the budget to
bankroll such 'Blue Sky' research projects. ICBMs sidelined the concept
of an always aloft bomber fleet so the technology, so promising a
solution as it was for civil nuclear power station design, was simply
left to languish.

If the 'Green Party' membership were to truly compare the *actual* cost/
benefit ratios of *all* the 'Green Options' Mother Nature Provides, LFTR
would win hands down on energy generation, environmental impact *and*
pollution costs. They wouldn't be able to tear down all those pointless
Wind Turbines fast enough!

Sadly, as you pointed out, it's humanity's propensity to short sighted
obsession with seemingly 'nice warm cozy 'cheap' 'feel good factor'
solutions that leads to wasted time and resources on sub-optimal
solutions. A shortsightedness that's invariably taken advantage of by the
"PT Barnum" "Get Rich Quick" type of individual or major corporate
business.

At the heart of all this, of course, is a nation's educational system
which, in the UK and America at least, is seriously lacking in teaching
the fundamental skills required to question gift horse offers and other
dubious claims such as that rather outrageous idea that the damaging
effects of nuclear radiation levels follow a totally contrary curve of
damage versus level which apply to all other forms of radiation exposure
such as UV light from solar radiation and the effects of microwave
radiation which have lead us into believing that almost impossibly
expensive anti-radiation precautions are required in Nuclear Power
Station design, making the Nuclear Power option infeasibly expensive.

Actually, the most expensive part of a Cold War type of Nuclear Power
Station is its Containment Vessel. A modern LFTR based design totally
does away with the need of such containment measures (along with an
expensive re-fueling process industry) whilst offering a 200 fold
improvement in energy yield from the nuclear fuel itself. As always,
"Ignorance"(tm) strikes again at the heart of the matter.

BTW, many a conspiracy theory nut would lay claim that the Oil and
Petrochemical industry are doing their best to scupper the idea of a
"Nuclear Powered World"(tm) when in fact it would be in their best
interests to branch out (diversify) into Nuclear Power Station design and
proliferation so they can corner the market in *synthesised*
petrochemicals and save the costs in dangerous exploration and drilling
for a dwindling natural resource.

--
Johnny B Good

On 27/06/2015 11:41, Jim x321x wrote:
John Rumm wrote in
o.uk:

Subject: Do I need to update my house's fuse box?
From: John Rumm
Newsgroups: uk.d-i-y

On 26/06/2015 09:12, Jim x321x wrote:
wrote in
:

On Wednesday, 24 June 2015 10:59:29 UTC+1, Jim x321x wrote:
Can someone tell me if I can get away with a 45A MCB for a 8.5kW
shower without endagering life and limb? The manual tells me to use
a 40A one, but I just happen to have a 45A one. I ask, because
those things aren't cheap.


Probably, as you're not relying on the MCB for overload protection
(as the load is fixed and unlikely to draw a higher than rated
current), merely for short circuit in the event of fault.

What is the cable size an mounting method.?

Owain



It's a 6mm^ T&E cable that is surface mounted all the way to the
8.5kW shower. (about 4ft goes through surface-mounted conduit.

Most of that is Method C, but the section of trunking means you need
to treat it all as Method B. That gives the cable a continuous rating
of 38A.


Your design current is 8500 / 230 = 37A, so you are ok there (just).

Many thanks for the detailed reply. So what would be the ideal rating of
MCB to use?

= The nominal load on the circuit... so the next one up from 37A
(typically 40A)

I just ordered a 40A one, because that's what the shower
manual recommends. The 45A one I had wasn't ideal because it wasn't a
Wylex one, and didn't fit without removing the base plate.

Jim



--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 26/06/2015 19:54, wrote:
On Friday, 26 June 2015 16:23:39 UTC+1, John Rumm wrote:


Not only that, as had been pointed out at various times, one
insures against losses that one can't otherwise replace. I
would include wife and children in that category, so a one off
premium of a couple of hundred for smoke alarms and RCDs sounds
like a very worthwhile investment.

2 different issues lumped together,

Smoke alarms and RCDs are different - however the risks associated
with not having either are comparable (although injury from fires
per years are far fewer than from electric shock).

200 something deaths a year in fires now, 20 something from shock

I said injury, not deaths.

So we appear to be in agreement that deaths from either cause are very
low. Yet I don't hear you claiming fire protection systems including
smoke alarms are also a waste of money?

I seem to recall someone round here was very fond of plastering
domestic fire safety stats into every wiki article given the
chance. Why the double standards?

why the claim of double standards? how would stating the known facts
possibly be that? Its not even worth answering.

I feel like I am talking to a truculent five year old, with his fingers
in his ears, going ner ner, can't hear you.

You keep bleating on about death rates as justification for your
(absurd) position. And yet everyone acknowledges that the death rate
alone would not be a justification for wide spread use of RCDs (or smoke
alarms for that matter).

I am not suggesting that if one lives in a property without RCDs, they
you should be fitted because it will prevent someone from dying from
electrocution - even though that is true - the actual chances that you
will die that way are very small, and not worth the expense unless you
are, due to circumstances, at a higher than normal risk.

I am however suggesting that everyone who lives in a property without
RCD protection *should* update to include them as a resonable priority.
This is because *millions* of people receive electric shocks each year.
Hundreds of thousands of them require hospital treatment. Tens of
thousands of those receive a significant injury, many have ongoing and
debilitating effects.

RCDs represent a very cheap way of reducing a cause of injury that
affects a significant number of people in the country every year. There
are few widespread risks that are so easy to deal with in such a low
cost "fit and forget" way.

and a non sequitur.

Explain

I already have. I've shown how I assessed whether RCDs were worth
fitting.

Even if your logic were sound, that does not explain the "non sequiter"
claim.

You have carried out an assessment ignoring the most relevant parts of
the data, and focussed your attention on a very small subset.

You simply did not address the necessary points in order to
reach a reason based case on the question of whether its a good
things to install your RCDs.

Maybe some of us just aren't into risk assessment.

You think... I wonder who?

I've offered a clear risk & cost asessment,

Which only demonstrated you have failed to asses the facts.

plus placed it in the
list of available risk reductions, thereby determining if its a
priority or whether there are far bigger priorities. Yours has so far
been an assessment of the risk followed by an illogical conclusion.
Unfortunately the approach you've shown is common today.

I agree that poor risk assessment is indeed common - its a part of human
nature and our evolution. We tend to greatly over estimate risks that
are perceived to be outside of our control, or that are newsworthy, and
imminent. While we tend to be complacent with risks that are familiar
and common, or only affect us in the very long term. Its why many people
fear flying, but not driving, worry about being raped in the street, but
not heart disease. Fear terrorism, but drive on bald tyres.

I don't agree that my assessment in this particular case is a
manifestation of this phenomenon.

It results
in people spending on tiny risks and consequently neglecting the big
ones. No-one has the resources to address all risks, so the sensible
approach is to prioritise the ones we can reduce the most.

I would agree with that.

That is
evidently not RCDs, unless you've effectively tackled a fairly long
list of others already.

Much depends on what is on your list. Fix the loose stair carpet at the
top of the stairs, do something about the ancient boiler that makes you
feel all drowsy every time its fired up. If there is water running down
the walls, and mould everywhere you may have more urgent fish to fry.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Sunday, 28 June 2015 06:50:57 UTC+1, John Rumm wrote:
If there is water running down
the walls, and mould everywhere

.... then RCD on the wiring is probably a very good idea in case your walls become live.

Owain

wrote:
On Sunday, 28 June 2015 06:50:57 UTC+1, John Rumm wrote:
If there is water running down
the walls, and mould everywhere

... then RCD on the wiring is probably a very good idea in case your
walls become live.

But the RCD might stop electrolysis of the water which might in turn be
giving rise to a disinfectant that stops bugs breeding on the walls?
More risk assessment is needed! bg.

--
Robin
reply to address is (meant to be) valid

On Sunday, 28 June 2015 06:50:57 UTC+1, John Rumm wrote:
On 26/06/2015 19:54, nt wrote:
On Friday, 26 June 2015 16:23:39 UTC+1, John Rumm wrote:

Not only that, as had been pointed out at various times, one
insures against losses that one can't otherwise replace. I
would include wife and children in that category, so a one off
premium of a couple of hundred for smoke alarms and RCDs sounds
like a very worthwhile investment.

2 different issues lumped together,

Smoke alarms and RCDs are different - however the risks associated
with not having either are comparable (although injury from fires
per years are far fewer than from electric shock).

200 something deaths a year in fires now, 20 something from shock

I said injury, not deaths.

We know

So we appear to be in agreement that deaths from either cause are very
low. Yet I don't hear you claiming fire protection systems including
smoke alarms are also a waste of money?

A few pounds per family to save most of 1000 deaths a year is a good deal.
£3 x 20m houses = £60m
Lives saved if the alarms survive 10-20 yrs ave = 15yrs x 1000pa (number before smoke alarms were common) = 15,000 lives
= £4,000 per life saved.
Batteries increase that, but still a fine deal.


I seem to recall someone round here was very fond of plastering
domestic fire safety stats into every wiki article given the
chance. Why the double standards?

why the claim of double standards? how would stating the known facts
possibly be that? Its not even worth answering.

I feel like I am talking to a truculent five year old, with his fingers
in his ears, going ner ner, can't hear you.

ah, ad hominem. I think what you mean is that the point(s) we see as key are different.

You keep bleating on about death rates as justification for your
(absurd) position. And yet everyone acknowledges that the death rate
alone would not be a justification for wide spread use of RCDs

we agree on that then

(or smoke
alarms for that matter).

the figures do not support that position.

snip

I am however suggesting that everyone who lives in a property without
RCD protection *should* update to include them as a resonable priority.
This is because *millions* of people receive electric shocks each year.
Hundreds of thousands of them require hospital treatment. Tens of
thousands of those receive a significant injury, many have ongoing and
debilitating effects.

Your injury data is wrong due to you not undersanding the situation.


RCDs represent a very cheap way of reducing a cause of injury that
affects a significant number of people in the country every year. There
are few widespread risks that are so easy to deal with in such a low
cost "fit and forget" way.

and a non sequitur.

Explain

I already have. I've shown how I assessed whether RCDs were worth
fitting.

Even if your logic were sound, that does not explain the "non sequiter"
claim.

feel free to listen to the reply first

You have carried out an assessment ignoring the most relevant parts of
the data, and focussed your attention on a very small subset.

in your opinion. Many don't see risk assessment that way. Your faulty injury assessment is a good example of why.

You simply did not address the necessary points in order to
reach a reason based case on the question of whether its a good
things to install your RCDs.

Maybe some of us just aren't into risk assessment.

You think... I wonder who?

I've offered a clear risk & cost asessment,

Which only demonstrated you have failed to asses the facts.

rather it confirms that we differ on what's most important, and what actually are the facts. Your injury stats are, I'm sorry to say, bunk.


snip
It results
in people spending on tiny risks and consequently neglecting the big
ones. No-one has the resources to address all risks, so the sensible
approach is to prioritise the ones we can reduce the most.

I would agree with that.

That is
evidently not RCDs, unless you've effectively tackled a fairly long
list of others already.

Much depends on what is on your list. Fix the loose stair carpet at the
top of the stairs, do something about the ancient boiler that makes you
feel all drowsy every time its fired up. If there is water running down
the walls, and mould everywhere you may have more urgent fish to fry.

the top 10 killers or death risks aren't those things, at least for over 99% of us. Most people have not even dealt with the top few.

I say put the time & money towards doing something about one of those instead, you'll get over 1000x the risk reduction benefit.


NT

On Sunday, 28 June 2015 12:06:47 UTC+1, Robin wrote:
wrote:
On Sunday, 28 June 2015 06:50:57 UTC+1, John Rumm wrote:
If there is water running down
the walls, and mould everywhere

... then RCD on the wiring is probably a very good idea in case your
walls become live.

But the RCD might stop electrolysis of the water which might in turn be
giving rise to a disinfectant that stops bugs breeding on the walls?
More risk assessment is needed! bg.

hehe. electrolysis with copper does kill bugs.


NT

On 28/06/2015 17:47, wrote:
On Sunday, 28 June 2015 06:50:57 UTC+1, John Rumm wrote:
On 26/06/2015 19:54, nt wrote:
On Friday, 26 June 2015 16:23:39 UTC+1, John Rumm wrote:

Not only that, as had been pointed out at various times,
one insures against losses that one can't otherwise
replace. I would include wife and children in that
category, so a one off premium of a couple of hundred for
smoke alarms and RCDs sounds like a very worthwhile
investment.

2 different issues lumped together,

Smoke alarms and RCDs are different - however the risks
associated with not having either are comparable (although
injury from fires per years are far fewer than from electric
shock).

200 something deaths a year in fires now, 20 something from
shock

I said injury, not deaths.

We know

So we appear to be in agreement that deaths from either cause are
very low. Yet I don't hear you claiming fire protection systems
including smoke alarms are also a waste of money?

A few pounds per family to save most of 1000 deaths a year is a good

Where do you get 1000 deaths per year from? In 2013 - 14 there were 258
dwelling fire fatalities (from a total of 40375 dwelling fires)

https://www.gov.uk/government/upload...F_Version_.pdf

deal. £3 x 20m houses = £60m Lives saved if the alarms survive 10-20

Where do you get £3 from? Even a single cheap detector is typically more
than that, and that is far from a recommended install. (i.e. mains
interlinked alarms in all of the main circulation spaces in the home)

yrs ave = 15yrs x 1000pa (number before smoke alarms were common) =
15,000 lives = £4,000 per life saved. Batteries increase that, but
still a fine deal.

In the same period, there were 7798 non fatal casualties from dwelling
fires.

(compare this to the 350,000 / year serious injury rate from a total of
2.5m electrical shocks!)

http://www.electricalsafetyfirst.org...ch/statistics/

I seem to recall someone round here was very fond of
plastering domestic fire safety stats into every wiki article
given the chance. Why the double standards?

why the claim of double standards? how would stating the known
facts possibly be that? Its not even worth answering.

I feel like I am talking to a truculent five year old, with his
fingers in his ears, going ner ner, can't hear you.

ah, ad hominem. I think what you mean is that the point(s) we see as
key are different.

No, I mean we both agree that death rates are not a good indication of
the risks involved, and yet you repeatedly cite them as justification of
your position.

You keep bleating on about death rates as justification for your
(absurd) position. And yet everyone acknowledges that the death
rate alone would not be a justification for wide spread use of
RCDs

we agree on that then

(or smoke alarms for that matter).

the figures do not support that position.

Do you mean the figures indicate far more strongly the importance of RCDs?

I am however suggesting that everyone who lives in a property
without RCD protection *should* update to include them as a
resonable priority. This is because *millions* of people receive
electric shocks each year. Hundreds of thousands of them require
hospital treatment. Tens of thousands of those receive a
significant injury, many have ongoing and debilitating effects.

Your injury data is wrong due to you not undersanding the situation.

Can you provide alternate data?

Can you sand it better for us?

RCDs represent a very cheap way of reducing a cause of injury that
affects a significant number of people in the country every year.
There are few widespread risks that are so easy to deal with in
such a low cost "fit and forget" way.

and a non sequitur.

Explain

I already have. I've shown how I assessed whether RCDs were
worth fitting.

Even if your logic were sound, that does not explain the "non
sequiter" claim.

feel free to listen to the reply first

You have carried out an assessment ignoring the most relevant parts
of the data, and focussed your attention on a very small subset.

in your opinion. Many don't see risk assessment that way. Your faulty
injury assessment is a good example of why.

Why do you believe the injury assessment is faulty?

You simply did not address the necessary points in order to reach
a reason based case on the question of whether its a good things
to install your RCDs.

Maybe some of us just aren't into risk assessment.

You think... I wonder who?

I've offered a clear risk & cost asessment,

Which only demonstrated you have failed to asses the facts.

rather it confirms that we differ on what's most important, and what
actually are the facts. Your injury stats are, I'm sorry to say,
bunk.

So provide better data... with sources!


snip
It results in people spending on tiny risks and consequently
neglecting the big ones. No-one has the resources to address all
risks, so the sensible approach is to prioritise the ones we can
reduce the most.

I would agree with that.

That is evidently not RCDs, unless you've effectively tackled a
fairly long list of others already.

Much depends on what is on your list. Fix the loose stair carpet at
the top of the stairs, do something about the ancient boiler that
makes you feel all drowsy every time its fired up. If there is
water running down the walls, and mould everywhere you may have
more urgent fish to fry.

the top 10 killers or death risks aren't those things, at least for
over 99% of us. Most people have not even dealt with the top few.

You seem to be confusing statistics applicable to the general population
with those applicable to an "at risk" subset.

CO poisoning is not a top 10 killer (see you are back to deaths again!)
in the general population. That is because faulty gas appliances (or
other sources of CO in the home) are not common in the general
population. However in this case I was citing the subset of people that
actually *have* a faulty gas appliance. Here the risks of CO poisoning
will be many *orders of magnitude* greater than those for the general
population.

I say put the time & money towards doing something about one of those
instead, you'll get over 1000x the risk reduction benefit.

Do you have some examples of these injury risks, and how you plan to
reduce those risks by 1000x?


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Monday, 29 June 2015 03:18:41 UTC+1, John Rumm wrote:
On 28/06/2015 17:47, nt wrote:
On Sunday, 28 June 2015 06:50:57 UTC+1, John Rumm wrote:
On 26/06/2015 19:54, nt wrote:
On Friday, 26 June 2015 16:23:39 UTC+1, John Rumm wrote:

200 something deaths a year in fires now, 20 something from
shock

I said injury, not deaths.

We know

So we appear to be in agreement that deaths from either cause are
very low. Yet I don't hear you claiming fire protection systems
including smoke alarms are also a waste of money?

A few pounds per family to save most of 1000 deaths a year is a good

Where do you get 1000 deaths per year from? In 2013 - 14 there were 258
dwelling fire fatalities (from a total of 40375 dwelling fires)

https://www.gov.uk/government/upload...F_Version_.pdf

As I said, before smoke alarms became common there were about 1000 deaths a year. The main change since then has been widespread use of smoke alarms. Its reasonable to conclude that with no smoke alarm the risk is nearer 1000/yr than the current 200 odd.


deal. £3 x 20m houses = £60m Lives saved if the alarms survive 10-20

Where do you get £3 from? Even a single cheap detector is typically more
than that, and that is far from a recommended install. (i.e. mains
interlinked alarms in all of the main circulation spaces in the home)

but its what most people use. If you want to calculate costs & payback for other options you can.


yrs ave = 15yrs x 1000pa (number before smoke alarms were common) =
15,000 lives = £4,000 per life saved. Batteries increase that, but
still a fine deal.

In the same period, there were 7798 non fatal casualties from dwelling
fires.

(compare this to the 350,000 / year serious injury rate from a total of
2.5m electrical shocks!)

http://www.electricalsafetyfirst.org...ch/statistics/

the relvant line there is:

'People receiving a mains voltage electric shock per year (15+): 2.5 million*
Of whom received a serious injury: 350,000**'

If that is correct, we would have, with average life expectancy apx 80, 80x350,000 people in the uk who have been seriously injured by shock. That's 28 million! The most basic sanity check shows that to be wildly unrealistic.
And to make that more precise, since shock protection measures have greatly improved in the last 80 years, the actual figure would be far higher, if their claim were true.

You always need to look at the source and assess the data. Its pretty obvious they're a group promoting increase of electrical safety, and pretty obvious that a lot of people mislead & even lie routinely when they have an agenda to pursue.


I seem to recall someone round here was very fond of
plastering domestic fire safety stats into every wiki article
given the chance. Why the double standards?

why the claim of double standards? how would stating the known
facts possibly be that? Its not even worth answering.

I feel like I am talking to a truculent five year old, with his
fingers in his ears, going ner ner, can't hear you.

ah, ad hominem. I think what you mean is that the point(s) we see as
key are different.

No, I mean we both agree that death rates are not a good indication of
the risks involved, and yet you repeatedly cite them as justification of
your position.

For good reason. These kind of analyses are routinely based on death rates as they're far more reliable data, and a much more serious problem.


You keep bleating on about death rates as justification for your
(absurd) position. And yet everyone acknowledges that the death
rate alone would not be a justification for wide spread use of
RCDs

we agree on that then

(or smoke alarms for that matter).

the figures do not support that position.

Do you mean the figures indicate far more strongly the importance of RCDs?

I don't mean anything of the sort. I mean the figures above show smoke alarms to be a good deal.


I am however suggesting that everyone who lives in a property
without RCD protection *should* update to include them as a
resonable priority. This is because *millions* of people receive
electric shocks each year. Hundreds of thousands of them require
hospital treatment. Tens of thousands of those receive a
significant injury, many have ongoing and debilitating effects.

Your injury data is wrong due to you not undersanding the situation.

Can you provide alternate data?

I'm not going to look for it. That does not mean we should base a decision on data that's patently false.


Can you sand it better for us?




RCDs represent a very cheap way of reducing a cause of injury that
affects a significant number of people in the country every year.
There are few widespread risks that are so easy to deal with in
such a low cost "fit and forget" way.

and a non sequitur.

Explain

I already have. I've shown how I assessed whether RCDs were
worth fitting.

Even if your logic were sound, that does not explain the "non
sequiter" claim.

feel free to listen to the reply first

You have carried out an assessment ignoring the most relevant parts
of the data, and focussed your attention on a very small subset.

in your opinion. Many don't see risk assessment that way. Your faulty
injury assessment is a good example of why.

Why do you believe the injury assessment is faulty?

You said in a previous post what it really was. The NHS routinely admits people and sends ambulances for people that are uninjured in situations where they know there is some risk of a situation turning out to be fatal, even when the risk is quite small. So it is with shock. The figure you gave is far from the number actually injured.


You simply did not address the necessary points in order to reach
a reason based case on the question of whether its a good things
to install your RCDs.

Maybe some of us just aren't into risk assessment.

You think... I wonder who?

I've offered a clear risk & cost asessment,

Which only demonstrated you have failed to asses the facts.

rather it confirms that we differ on what's most important, and what
actually are the facts. Your injury stats are, I'm sorry to say,
bunk.

So provide better data... with sources!

Sorry but no, I have way more useful things to do, and really I'm not concerned about it. If you want to provide a case for retrofitting RCDs you're free to.


It results in people spending on tiny risks and consequently
neglecting the big ones. No-one has the resources to address all
risks, so the sensible approach is to prioritise the ones we can
reduce the most.

I would agree with that.

That is evidently not RCDs, unless you've effectively tackled a
fairly long list of others already.

Much depends on what is on your list. Fix the loose stair carpet at
the top of the stairs, do something about the ancient boiler that
makes you feel all drowsy every time its fired up. If there is
water running down the walls, and mould everywhere you may have
more urgent fish to fry.

the top 10 killers or death risks aren't those things, at least for
over 99% of us. Most people have not even dealt with the top few.

You seem to be confusing statistics applicable to the general population
with those applicable to an "at risk" subset.

The top 10 apply to everyone.

CO poisoning is not a top 10 killer (see you are back to deaths again!)
in the general population. That is because faulty gas appliances (or
other sources of CO in the home) are not common in the general
population. However in this case I was citing the subset of people that
actually *have* a faulty gas appliance. Here the risks of CO poisoning
will be many *orders of magnitude* greater than those for the general
population.

there's little point discussing that, it has nothing to do with the main point


I say put the time & money towards doing something about one of those
instead, you'll get over 1000x the risk reduction benefit.

Do you have some examples of these injury risks,

As I've made clear all along, they're death risks. I can't believe you're still confused about that.


and how you plan to
reduce those risks by 1000x?

Why would anyone try to reduce them 1000fold?
Reducing a risk over 1000x as large is over 1000x as beneficial as fitting RCDs, which in truth have only a very very tiny chance of saving your life.


NT

On 29/06/2015 15:15, wrote:
As I said, before smoke alarms became common there were about 1000 deaths a year. The
main change since then has been widespread use of smoke alarms. Its
reasonable to
conclude that with no smoke alarm the risk is nearer 1000/yr than the
current 200 odd.

I don't believe that the main change has been the widespread use of
smoke alarms.

People stopping smoking will have a big impact. Continued improvement of
electrics will be another. Central heating another.

wrote:
Where do you get 1000 deaths per year from? In 2013 - 14 there were
258 dwelling fire fatalities (from a total of 40375 dwelling fires)

https://www.gov.uk/government/upload...F_Version_.pdf

As I said, before smoke alarms became common there were about 1000
deaths a year. The main change since then has been widespread use of
smoke alarms. Its reasonable to conclude that with no smoke alarm the
risk is nearer 1000/yr than the current 200 odd.

That's an heroic assumption.

First, you give no credit to the reduction in the total number of fires
in dwellings (down 40% since 2000/01). Given there's no smoke without
fire I douibt smoke alarms contributed to that.

Second, the report states that the "proportion of households with a
smoke alarm increased rapidly from 8% in 1988 to 70% in 1994 in England,
but has risen more slowly in later years up to 88% has at least one
working smoke alarm in 2012-13". So fatalities peaked well after smoke
alarms had penetrated most dwellings but have then fallen much faster
than can be explained by the additional penetration.

Of course there *might* be effects from better smoke alarms, including
interlinked alarms with mains supply. But you'd need a better argued
impact assessment to support regulations to require them. (Of course if
you can get the requirement in by means of a BS then you may welkl not
need an impact assessment with costs and benefits quantified: I have yet
to see one for Amendment 3 to BS 7671:2008 and non-combustible CUs.)

--
Robin
reply to address is (meant to be) valid

On Monday, June 29, 2015 at 3:16:01 PM UTC+1, wrote:
On Monday, 29 June 2015 03:18:41 UTC+1, John Rumm wrote:
snip
http://www.electricalsafetyfirst.org...ch/statistics/

the relvant line there is:

'People receiving a mains voltage electric shock per year (15+): 2.5 million*
Of whom received a serious injury: 350,000**'

If that is correct, we would have, with average life expectancy apx 80, 80x350,000 people in the uk who have been seriously injured by shock. That's 28 million! The most basic sanity check shows that to be wildly unrealistic.
And to make that more precise, since shock protection measures have greatly improved in the last 80 years, the actual figure would be far higher, if their claim were true.

You always need to look at the source and assess the data. Its pretty obvious they're a group promoting increase of electrical safety, and pretty obvious that a lot of people mislead & even lie routinely when they have an agenda to pursue.


I notice (looking further down the quoted page) that the figure for electric shock comes from the answers given in interviews with 4032 people over 15.. Apparently the people were selected to be a 'representative quota sample' and the results weighted to represent the known profile of the adult population of GB.What we don't know is the way the questions were phrased.
What I really don't understand is how they calculate the figure for injuries, given that they say they were obtained by surveying 4032 adults *all* of whom had received an electric shock injury...

On 29/06/2015 15:15, wrote:
On Monday, 29 June 2015 03:18:41 UTC+1, John Rumm wrote:
On 28/06/2015 17:47, nt wrote:
On Sunday, 28 June 2015 06:50:57 UTC+1, John Rumm wrote:
On 26/06/2015 19:54, nt wrote:
On Friday, 26 June 2015 16:23:39 UTC+1, John Rumm wrote:

200 something deaths a year in fires now, 20 something from
shock

I said injury, not deaths.

We know

So we appear to be in agreement that deaths from either cause
are very low. Yet I don't hear you claiming fire protection
systems including smoke alarms are also a waste of money?

A few pounds per family to save most of 1000 deaths a year is a
good

Where do you get 1000 deaths per year from? In 2013 - 14 there were
258 dwelling fire fatalities (from a total of 40375 dwelling
fires)

https://www.gov.uk/government/upload...F_Version_.pdf


As I said, before smoke alarms became common there were about 1000
deaths a year. The main change since then has been widespread use of
smoke alarms. Its reasonable to conclude that with no smoke alarm the
risk is nearer 1000/yr than the current 200 odd.

What has the situation in the past got to do with recommendations one
would make now?

deal. £3 x 20m houses = £60m Lives saved if the alarms survive
10-20

Where do you get £3 from? Even a single cheap detector is typically
more than that, and that is far from a recommended install. (i.e.
mains interlinked alarms in all of the main circulation spaces in
the home)

but its what most people use. If you want to calculate costs &
payback for other options you can.

I would suggest most people pay in excess of £10 per alarm, and buy at
least two of them. A proper install to modern standards would cost
significantly more.

yrs ave = 15yrs x 1000pa (number before smoke alarms were common)
= 15,000 lives = £4,000 per life saved. Batteries increase that,
but still a fine deal.

In the same period, there were 7798 non fatal casualties from
dwelling fires.

(compare this to the 350,000 / year serious injury rate from a
total of 2.5m electrical shocks!)

http://www.electricalsafetyfirst.org...ch/statistics/


the relvant line there is:

'People receiving a mains voltage electric shock per year (15+): 2.5
million* Of whom received a serious injury: 350,000**'

Did you read the ** footnote?

If that is correct, we would have, with average life expectancy apx
80, 80x350,000 people in the uk who have been seriously injured by

The figures are for those over 15 anyway, and if including those who are
80 now, they would predate modern wiring practices.

You are also assuming that those shocked each year are unique - when in
reality some adults will be far more likely to receive a shock than
others. You will have many "serial offenders" here.

shock. That's 28 million! The most basic sanity check shows that to
be wildly unrealistic.

No, it shows you did not read the footnote. Their definition of serious
injury :

**Based on a survey of 4,032 adults in Great Britain aged 15+ who have
personally experienced an electric shock that resulted in injury while
at home or in the garden in the past twelve months including all those
who experienced one or more of the following injuries: Severe pain, Skin
burn without scarring, Bruising from a fall or severe muscular
contraction, Temporary blindness, Heartbeat disturbance, Persistent pain
or numbness, Higher blood pressure, Skin burn with scarring, Broken
bone(s), Difficulty breathing.'

A number of which are recoverable from. From memory, there was something
like 5k - 10k in the most serious categories

And to make that more precise, since shock
protection measures have greatly improved in the last 80 years, the
actual figure would be far higher, if their claim were true.
You always need to look at the source and assess the data. Its pretty
obvious they're a group promoting increase of electrical safety, and
pretty obvious that a lot of people mislead & even lie routinely when
they have an agenda to pursue.

I fully accept they have an agenda, and that they have over stated the
figures for serious injury by including less serious injuries into the
"serious" category.

However, Even if 10x out (which is unlikely) that would still be plenty
of justification for the current regulations on the use of RCDs.

I seem to recall someone round here was very fond of
plastering domestic fire safety stats into every wiki
article given the chance. Why the double standards?

why the claim of double standards? how would stating the
known facts possibly be that? Its not even worth answering.

I feel like I am talking to a truculent five year old, with
his fingers in his ears, going ner ner, can't hear you.

ah, ad hominem. I think what you mean is that the point(s) we see
as key are different.

No, I mean we both agree that death rates are not a good indication
of the risks involved, and yet you repeatedly cite them as
justification of your position.

For good reason. These kind of analyses are routinely based on death
rates as they're far more reliable data, and a much more serious
problem.

Make your mind up.

You keep bleating on about death rates as justification for
your (absurd) position. And yet everyone acknowledges that the
death rate alone would not be a justification for wide spread
use of RCDs

we agree on that then

(or smoke alarms for that matter).

the figures do not support that position.

Do you mean the figures indicate far more strongly the importance
of RCDs?

I don't mean anything of the sort. I mean the figures above show
smoke alarms to be a good deal.

But they show them as a less "good deal" than the results being achieved
with RCDs.

I am however suggesting that everyone who lives in a property
without RCD protection *should* update to include them as a
resonable priority. This is because *millions* of people
receive electric shocks each year. Hundreds of thousands of
them require hospital treatment. Tens of thousands of those
receive a significant injury, many have ongoing and
debilitating effects.

Your injury data is wrong due to you not undersanding the
situation.

Can you provide alternate data?

I'm not going to look for it. That does not mean we should base a
decision on data that's patently false.

So you would rather base a decision on no data at all apparently?

in your opinion. Many don't see risk assessment that way. Your
faulty injury assessment is a good example of why.

Why do you believe the injury assessment is faulty?

You said in a previous post what it really was. The NHS routinely
admits people and sends ambulances for people that are uninjured in
situations where they know there is some risk of a situation turning
out to be fatal, even when the risk is quite small. So it is with
shock. The figure you gave is far from the number actually injured.

Go read the footnote again. I would not not necessarily include bruising
and burns with no permanent scarring in the "serious" category. However
the rest seem reasonable to include.

You simply did not address the necessary points in order to
reach a reason based case on the question of whether its a
good things to install your RCDs.

Maybe some of us just aren't into risk assessment.

You think... I wonder who?

I've offered a clear risk & cost asessment,

Which only demonstrated you have failed to asses the facts.

rather it confirms that we differ on what's most important, and
what actually are the facts. Your injury stats are, I'm sorry to
say, bunk.

So provide better data... with sources!

Sorry but no, I have way more useful things to do, and really I'm not
concerned about it. If you want to provide a case for retrofitting
RCDs you're free to.

So you are content to counter the advice given by many here on RCDs, and
yet can't be arsed (or more likely, could not find when you looked!) to
backup your position with data when asked to justify the advice you offer?

Yet have enough time to argue about it?


It results in people spending on tiny risks and consequently
neglecting the big ones. No-one has the resources to address
all risks, so the sensible approach is to prioritise the ones
we can reduce the most.

I would agree with that.

That is evidently not RCDs, unless you've effectively tackled
a fairly long list of others already.

Much depends on what is on your list. Fix the loose stair
carpet at the top of the stairs, do something about the ancient
boiler that makes you feel all drowsy every time its fired up.
If there is water running down the walls, and mould everywhere
you may have more urgent fish to fry.

the top 10 killers or death risks aren't those things, at least
for over 99% of us. Most people have not even dealt with the top
few.

You seem to be confusing statistics applicable to the general
population with those applicable to an "at risk" subset.

The top 10 apply to everyone.

Obviously they don't. Do you suppose that the risks of CO poisoning in
the home are the same for people who don't have gas?

CO poisoning is not a top 10 killer (see you are back to deaths
again!) in the general population. That is because faulty gas
appliances (or other sources of CO in the home) are not common in
the general population. However in this case I was citing the
subset of people that actually *have* a faulty gas appliance. Here
the risks of CO poisoning will be many *orders of magnitude*
greater than those for the general population.

there's little point discussing that, it has nothing to do with the
main point

It has *everything* to do with risk assessment which you claim to have
some competency in.

I say put the time & money towards doing something about one of
those instead, you'll get over 1000x the risk reduction benefit.

Do you have some examples of these injury risks,

As I've made clear all along, they're death risks.

LoL, is it panto season already?

I can't believe
you're still confused about that.

I am confused since you talk about all these risks that are higher
priority, and yet don't seem to be able to state what any of them are.


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On 29/06/2015 16:58, wrote:
On Monday, June 29, 2015 at 3:16:01 PM UTC+1,
wrote:
On Monday, 29 June 2015 03:18:41 UTC+1, John Rumm wrote:
snip
http://www.electricalsafetyfirst.org...ch/statistics/



the relvant line there is:

'People receiving a mains voltage electric shock per year (15+):
2.5 million* Of whom received a serious injury: 350,000**'

If that is correct, we would have, with average life expectancy apx
80, 80x350,000 people in the uk who have been seriously injured by
shock. That's 28 million! The most basic sanity check shows that to
be wildly unrealistic. And to make that more precise, since shock
protection measures have greatly improved in the last 80 years, the
actual figure would be far higher, if their claim were true.

You always need to look at the source and assess the data. Its
pretty obvious they're a group promoting increase of electrical
safety, and pretty obvious that a lot of people mislead & even lie
routinely when they have an agenda to pursue.


I notice (looking further down the quoted page) that the figure for
electric shock comes from the answers given in interviews with 4032
people over 15. Apparently the people were selected to be a
'representative quota sample' and the results weighted to represent
the known profile of the adult population of GB.What we don't know is
the way the questions were phrased. What I really don't understand is
how they calculate the figure for injuries, given that they say they
were obtained by surveying 4032 adults *all* of whom had received an
electric shock injury...

I think that is worded poorly, but makes more sense if taken with the
"*" para above:

" *4,032 interviews were conducted with adults in Great Britain aged 15+
from 06 to 27 May 2011 via Ipsos MORI's Capibus, the weekly face-to-face
omnibus survey, using a nationally representative quota sample across
Great Britain. The results have been weighted to reflect the known
profile of the adult population in Great Britain. Based on a confidence
interval of +/- 0.9% and the sample size of 4,032 the actual number
could vary between c2.1 to 2.8 million. Electric shock is defined as 'a
mains-voltage electric shock rather than a static shock of the type a
person might get from a car, for example.'"

So that suggests that not all 4032 received shocks - but a proportion
did, and that yields the ~2.5m figure. The detail of the effects of
shocks reported would then yield the "serious" figure.

(I also recall posting stats from hospital admissions in the admitted
for treatment for electrical related injury. That also had a spread
"seriousness" ranging from the pain / bruising, through broken bones,
and more permanent conditions, up to the more immediately life threatening).

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Tuesday, 30 June 2015 16:55:58 UTC+1, John Rumm wrote:
Electric shock is defined as 'a mains-voltage electric shock

So not the one I got sticking my fingers inside the valve radio then.

Owain

On Tuesday, 30 June 2015 16:21:45 UTC+1, John Rumm wrote:
On 29/06/2015 15:15, nt wrote:
On Monday, 29 June 2015 03:18:41 UTC+1, John Rumm wrote:
On 28/06/2015 17:47, nt wrote:
On Sunday, 28 June 2015 06:50:57 UTC+1, John Rumm wrote:
On 26/06/2015 19:54, nt wrote:
On Friday, 26 June 2015 16:23:39 UTC+1, John Rumm wrote:

200 something deaths a year in fires now, 20 something from
shock

I said injury, not deaths.

We know

So we appear to be in agreement that deaths from either cause
are very low. Yet I don't hear you claiming fire protection
systems including smoke alarms are also a waste of money?

A few pounds per family to save most of 1000 deaths a year is a
good

Where do you get 1000 deaths per year from? In 2013 - 14 there were
258 dwelling fire fatalities (from a total of 40375 dwelling
fires)

https://www.gov.uk/government/upload...F_Version_.pdf


As I said, before smoke alarms became common there were about 1000
deaths a year. The main change since then has been widespread use of
smoke alarms. Its reasonable to conclude that with no smoke alarm the
risk is nearer 1000/yr than the current 200 odd.

What has the situation in the past got to do with recommendations one
would make now?

how ever else do you propose to assess what difference smoke alarms have made? Go on, show us your assessment. Maybe you can use Robin's info for a more accurate result, but I can't imagine how you intend to work it out without using past figures.


deal. £3 x 20m houses = £60m Lives saved if the alarms survive
10-20

Where do you get £3 from? Even a single cheap detector is typically
more than that, and that is far from a recommended install. (i.e.
mains interlinked alarms in all of the main circulation spaces in
the home)

but its what most people use. If you want to calculate costs &
payback for other options you can.

I would suggest most people pay in excess of £10 per alarm, and buy at
least two of them. A proper install to modern standards would cost
significantly more.

yrs ave = 15yrs x 1000pa (number before smoke alarms were common)
= 15,000 lives = £4,000 per life saved. Batteries increase that,
but still a fine deal.

In the same period, there were 7798 non fatal casualties from
dwelling fires.

(compare this to the 350,000 / year serious injury rate from a
total of 2.5m electrical shocks!)

http://www.electricalsafetyfirst.org...ch/statistics/


the relvant line there is:

'People receiving a mains voltage electric shock per year (15+): 2.5
million* Of whom received a serious injury: 350,000**'

Did you read the ** footnote?

yes... did you have a point?


If that is correct, we would have, with average life expectancy apx
80, 80x350,000 people in the uk who have been seriously injured by

The figures are for those over 15 anyway, and if including those who are
80 now, they would predate modern wiring practices.

yes...

You are also assuming that those shocked each year are unique - when in
reality some adults will be far more likely to receive a shock than
others. You will have many "serial offenders" here.

I don't recall making that assumption

shock. That's 28 million! The most basic sanity check shows that to
be wildly unrealistic.

No, it shows you did not read the footnote. Their definition of serious
injury :

**Based on a survey of 4,032 adults in Great Britain aged 15+ who have
personally experienced an electric shock that resulted in injury while
at home or in the garden in the past twelve months including all those
who experienced one or more of the following injuries: Severe pain, Skin
burn without scarring, Bruising from a fall or severe muscular
contraction, Temporary blindness, Heartbeat disturbance, Persistent pain
or numbness, Higher blood pressure, Skin burn with scarring, Broken
bone(s), Difficulty breathing.'

At the risk of stating the utterly obvious, more or less all mains shocks involve considerable pain. Its also normal to experience elevated heart rate & blood pressure. None of these, according to any sensible definition, constitute serious injury. Nor do Bruises. The data is complete bunk.


A number of which are recoverable from. From memory, there was something
like 5k - 10k in the most serious categories

a little different to 2.5 million then!

And to make that more precise, since shock
protection measures have greatly improved in the last 80 years, the
actual figure would be far higher, if their claim were true.
You always need to look at the source and assess the data. Its pretty
obvious they're a group promoting increase of electrical safety, and
pretty obvious that a lot of people mislead & even lie routinely when
they have an agenda to pursue.

I fully accept they have an agenda, and that they have over stated the
figures for serious injury by including less serious injuries into the
"serious" category.

However, Even if 10x out (which is unlikely)

I agree 10x is unlikely. 100-1000x is far more likely. ISTR an estimate of 600x from a few years ago, but don't remember where it came from.


that would still be plenty
of justification for the current regulations on the use of RCDs.

I think we all agree RCDs in new installs are a good thing. What was being debated is the merits of retrofitting, where the cost & time involved are a good bit more.


I seem to recall someone round here was very fond of
plastering domestic fire safety stats into every wiki
article given the chance. Why the double standards?

why the claim of double standards? how would stating the
known facts possibly be that? Its not even worth answering.

I feel like I am talking to a truculent five year old, with
his fingers in his ears, going ner ner, can't hear you.

ah, ad hominem. I think what you mean is that the point(s) we see
as key are different.

No, I mean we both agree that death rates are not a good indication
of the risks involved, and yet you repeatedly cite them as
justification of your position.

For good reason. These kind of analyses are routinely based on death
rates as they're far more reliable data, and a much more serious
problem.

Make your mind up.

If you haven't got it yet that I'm interested in deaths not injuries, then there's no point us continuing.


You keep bleating on about death rates as justification for
your (absurd) position. And yet everyone acknowledges that the
death rate alone would not be a justification for wide spread
use of RCDs

we agree on that then

(or smoke alarms for that matter).

the figures do not support that position.

Do you mean the figures indicate far more strongly the importance
of RCDs?

I don't mean anything of the sort. I mean the figures above show
smoke alarms to be a good deal.

But they show them as a less "good deal" than the results being achieved
with RCDs.

Well, you're free to show us fatality figures that support that. You never have. All you've offered is junk stats that claim wild levels of injuries. This is precisely one of the reasons such decisions are so often made on mortality, not injury stats, the latter are far less reliable.


I am however suggesting that everyone who lives in a property
without RCD protection *should* update to include them as a
resonable priority. This is because *millions* of people
receive electric shocks each year. Hundreds of thousands of
them require hospital treatment. Tens of thousands of those
receive a significant injury, many have ongoing and
debilitating effects.

Your injury data is wrong due to you not undersanding the
situation.

Can you provide alternate data?

I'm not going to look for it. That does not mean we should base a
decision on data that's patently false.

So you would rather base a decision on no data at all apparently?

did you miss the stated death rates of shocks and the death rates from not eating well then? Keep this up and I'll start wondering if you've merged with Rodney.


in your opinion. Many don't see risk assessment that way. Your
faulty injury assessment is a good example of why.

Why do you believe the injury assessment is faulty?

You said in a previous post what it really was. The NHS routinely
admits people and sends ambulances for people that are uninjured in
situations where they know there is some risk of a situation turning
out to be fatal, even when the risk is quite small. So it is with
shock. The figure you gave is far from the number actually injured.

Go read the footnote again.

still no news there

I would not not necessarily include bruising
and burns with no permanent scarring in the "serious" category. However
the rest seem reasonable to include.

pain either, which about all have. Hence their crazy inflated figure.


You simply did not address the necessary points in order to
reach a reason based case on the question of whether its a
good things to install your RCDs.

Maybe some of us just aren't into risk assessment.

You think... I wonder who?

I've offered a clear risk & cost asessment,

Which only demonstrated you have failed to asses the facts.

rather it confirms that we differ on what's most important, and
what actually are the facts. Your injury stats are, I'm sorry to
say, bunk.

So provide better data... with sources!

Sorry but no, I have way more useful things to do, and really I'm not
concerned about it. If you want to provide a case for retrofitting
RCDs you're free to.

So you are content to counter the advice given by many here on RCDs, and
yet can't be arsed (or more likely, could not find when you looked!) to
backup your position with data when asked to justify the advice you offer?

Yet have enough time to argue about it?

The relevant data has beem stated again and again and again. Wakey wakey.


It results in people spending on tiny risks and consequently
neglecting the big ones. No-one has the resources to address
all risks, so the sensible approach is to prioritise the ones
we can reduce the most.

I would agree with that.

That is evidently not RCDs, unless you've effectively tackled
a fairly long list of others already.

Much depends on what is on your list. Fix the loose stair
carpet at the top of the stairs, do something about the ancient
boiler that makes you feel all drowsy every time its fired up.
If there is water running down the walls, and mould everywhere
you may have more urgent fish to fry.

the top 10 killers or death risks aren't those things, at least
for over 99% of us. Most people have not even dealt with the top
few.

You seem to be confusing statistics applicable to the general
population with those applicable to an "at risk" subset.

The top 10 apply to everyone.

Obviously they don't. Do you suppose that the risks of CO poisoning in
the home are the same for people who don't have gas?

I'd love to hear your CO stats that put that one into the top 10


CO poisoning is not a top 10 killer (see you are back to deaths
again!) in the general population. That is because faulty gas
appliances (or other sources of CO in the home) are not common in
the general population. However in this case I was citing the
subset of people that actually *have* a faulty gas appliance. Here
the risks of CO poisoning will be many *orders of magnitude*
greater than those for the general population.

there's little point discussing that, it has nothing to do with the
main point

It has *everything* to do with risk assessment which you claim to have
some competency in.

it makes no difference to the main point and is not worth discussing


I say put the time & money towards doing something about one of
those instead, you'll get over 1000x the risk reduction benefit.

Do you have some examples of these injury risks,

As I've made clear all along, they're death risks.

LoL, is it panto season already?

which bit is confusing?


I can't believe
you're still confused about that.

I am confused since you talk about all these risks that are higher
priority, and yet don't seem to be able to state what any of them are.

What makes you think that?

2010 mortality:
158k circulatory diseases
141k cancer & neoplasms
67k respiratory diseases
25k digestive diseases
19k dementia & mental disorders
18k nervous system diseases
17k accidents & injuries
12k genitourinary diseases
8k senility
5k diabetes

.... And according to the NHS, about 40 a year from CO.


NT

On 30/06/2015 22:11, wrote:
On Tuesday, 30 June 2015 16:21:45 UTC+1, John Rumm wrote:

What has the situation in the past got to do with recommendations
one would make now?

how ever else do you propose to assess what difference smoke alarms
have made?

Not by making wild claims of huge reductions in death rate and falsely
attributing that solely to smoke alarms, that is for sure. As Robin
pointed out, peak death occurred at a time when alarms were already well
established, and the recent falls in death rate do not correlate well
with the numbers of installed alarms. The data point to a much deeper
and more nuanced relationship.

(you do realise that people also install smoke alarms for reasons in
addition to saving their lives? Or is this another case where you house
going up is smoke is of no concern, just that you don't die in the process?)

'People receiving a mains voltage electric shock per year (15+):
2.5 million* Of whom received a serious injury: 350,000**'

Did you read the ** footnote?

yes... did you have a point?

You are claiming that their figures are implausible, without apparently
taking into account their definition of serious injury. The footnote
goes some way to explain why the number is so high.

If that is correct, we would have, with average life expectancy
apx 80, 80x350,000 people in the uk who have been seriously
injured by

The figures are for those over 15 anyway, and if including those
who are 80 now, they would predate modern wiring practices.

yes...

So your sums are nonsense as well.

You are also assuming that those shocked each year are unique -
when in reality some adults will be far more likely to receive a
shock than others. You will have many "serial offenders" here.

I don't recall making that assumption

the "80x350,000 people" sum was a bit of a give away.

shock. That's 28 million! The most basic sanity check shows that
to be wildly unrealistic.

How many people have you met who claim to have *never* received an
electrical shock? Many would meet the "serious" injury threshold set out
in the footnote.

No, it shows you did not read the footnote. Their definition of
serious injury :

**Based on a survey of 4,032 adults in Great Britain aged 15+ who
have personally experienced an electric shock that resulted in
injury while at home or in the garden in the past twelve months
including all those who experienced one or more of the following
injuries: Severe pain, Skin burn without scarring, Bruising from a
fall or severe muscular contraction, Temporary blindness, Heartbeat
disturbance, Persistent pain or numbness, Higher blood pressure,
Skin burn with scarring, Broken bone(s), Difficulty breathing.'

At the risk of stating the utterly obvious, more or less all mains
shocks involve considerable pain.

Indeed. That is also part of the justification for using RCDs - they
limit the duration of the shock and greatly reduce the pain.

Its also normal to experience
elevated heart rate & blood pressure. None of these, according to any
sensible definition, constitute serious injury.

Permanently elevated heart rate and blood pressure certainly count as
serious injury. Even temporary elevation will be a serious complication
for people with certain pre-existing conditions.

Nor do Bruises. The
data is complete bunk.

The data (while questionable) are by no means bunk. They have elevated
the figures by including some types of injury that one might argue are
less serious. However it is also very clear that even if the figures
were an order of magnitude out, for what you consider to be a serious
injury, you still have more than adequate justification for fitting
RCDs, and at worst, comparable justification to that for fitting smoke
alarms.

A number of which are recoverable from. From memory, there was
something like 5k - 10k in the most serious categories

a little different to 2.5 million then!

You do understand that not *all* shocks result in broken bones or
cardiac arrest?

The 2.5 million figure is the estimate of the number of mains voltage
shocks received by adults each year - not those enduring life changing
effects. Are you now being deliberately obtuse?

And to make that more precise, since shock protection measures
have greatly improved in the last 80 years, the actual figure
would be far higher, if their claim were true. You always need to
look at the source and assess the data. Its pretty obvious
they're a group promoting increase of electrical safety, and
pretty obvious that a lot of people mislead & even lie routinely
when they have an agenda to pursue.

I fully accept they have an agenda, and that they have over stated
the figures for serious injury by including less serious injuries
into the "serious" category.

However, Even if 10x out (which is unlikely)

I agree 10x is unlikely. 100-1000x is far more likely. ISTR an
estimate of 600x from a few years ago, but don't remember where it
came from.

Even 1000x would be one serious injury per day. The hospital treatment
stats I have seen in the past indicate the figure is well above that
however.

Still we should be able to resolve this question shortly:

http://www.rospa.com/home-safety/res...tion-database/

that would still be plenty of justification for the current
regulations on the use of RCDs.

I think we all agree RCDs in new installs are a good thing. What was
being debated is the merits of retrofitting, where the cost & time
involved are a good bit more.

There is not that much difference in cost between a new CU installation,
and a retrofit IME. The latter takes a little longer, but not
dramatically - only enough to label and disconnect the existing wiring.

If you haven't got it yet that I'm interested in deaths not injuries,
then there's no point us continuing.

I understand you have a narrow focus on deaths. That's fine by me. If
you are content to tolerate the far more typical outcome of an electric
shock, (i.e. pain and injury), rather than spend a couple of hundred
preventing / reducing the risk then by all means carry on.

However you then go on to give misleading advice to people contemplating
on fitting RCDs based on that very narrow viewpoint. For the vast
majority of people looking at retrofitting RCDs for the protection of
their families, the protection from death aspect is certainly a very
"nice to have" bonus, but since its also a very low likelihood
occurrence - its not a big part of the decision making process. The real
motivation for most will be the greatly enhanced protection from injury
and pain that matters more.

Well, you're free to show us fatality figures that support that. You
never have. All you've offered is junk stats that claim wild levels
of injuries. This is precisely one of the reasons such decisions are
so often made on mortality, not injury stats, the latter are far less
reliable.

Not much help when we are trying to prevent injury rather than mortality
though...

I am confused since you talk about all these risks that are higher
priority, and yet don't seem to be able to state what any of them
are.

What makes you think that?

2010 mortality: 158k circulatory diseases 141k cancer & neoplasms 67k
respiratory diseases 25k digestive diseases 19k dementia & mental
disorders 18k nervous system diseases 17k accidents & injuries 12k
genitourinary diseases 8k senility 5k diabetes

You appreciate we are all going to die from something eventually?

We are discussing protection from accidental injury in the home, not
long term lifestyle choices / genetic predispositions and eventual
outcomes on health.

Now which of the above can you fix in the home for a couple of hundred
quid?




--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Friday, 3 July 2015 01:30:27 UTC+1, John Rumm wrote:
On 30/06/2015 22:11, nt wrote:
On Tuesday, 30 June 2015 16:21:45 UTC+1, John Rumm wrote:

What has the situation in the past got to do with recommendations
one would make now?

how ever else do you propose to assess what difference smoke alarms
have made?

Not by making wild claims of huge reductions in death rate and falsely
attributing that solely to smoke alarms, that is for sure. As Robin
pointed out, peak death occurred at a time when alarms were already well
established, and the recent falls in death rate do not correlate well
with the numbers of installed alarms. The data point to a much deeper
and more nuanced relationship.

Sure, I accept that data needs improving. Are you able to offer better figures?

(you do realise that people also install smoke alarms for reasons in
addition to saving their lives? Or is this another case where you house
going up is smoke is of no concern, just that you don't die in the process?)

ok, I accept you're not focussed on the biggest risks, and determined to be silly.

'People receiving a mains voltage electric shock per year (15+):
2.5 million* Of whom received a serious injury: 350,000**'

Did you read the ** footnote?

yes... did you have a point?

You are claiming that their figures are implausible,

correct. it plainly is.

without apparently
taking into account their definition of serious injury. The footnote
goes some way to explain why the number is so high.

the footnotes explain why the claims are so ridiculous. I have explained this before. There is patently no basis for your claim they've been overlooked.

If that is correct, we would have, with average life expectancy
apx 80, 80x350,000 people in the uk who have been seriously
injured by

The figures are for those over 15 anyway, and if including those
who are 80 now, they would predate modern wiring practices.

yes...

So your sums are nonsense as well.

no, they're just rough ballpark which is enough to make the point. Feel free to offer better figures if you have them.


You are also assuming that those shocked each year are unique -
when in reality some adults will be far more likely to receive a
shock than others. You will have many "serial offenders" here.

I don't recall making that assumption

the "80x350,000 people" sum was a bit of a give away.

if you want to calculate it more precisely, despite the huge changes in wiring safety over the years, you're free to provide the necessary figures and calculate it. A ballpark is all it takes to make the relevant point.

shock. That's 28 million! The most basic sanity check shows that
to be wildly unrealistic.

How many people have you met who claim to have *never* received an
electrical shock?

can't say I've asked. Why would I?

Many would meet the "serious" injury threshold set out
in the footnote.

which is not, in any sensible definition, serious injury


No, it shows you did not read the footnote. Their definition of
serious injury :

**Based on a survey of 4,032 adults in Great Britain aged 15+ who
have personally experienced an electric shock that resulted in
injury while at home or in the garden in the past twelve months
including all those who experienced one or more of the following
injuries: Severe pain, Skin burn without scarring, Bruising from a
fall or severe muscular contraction, Temporary blindness, Heartbeat
disturbance, Persistent pain or numbness, Higher blood pressure,
Skin burn with scarring, Broken bone(s), Difficulty breathing.'

At the risk of stating the utterly obvious, more or less all mains
shocks involve considerable pain.

Indeed. That is also part of the justification for using RCDs - they
limit the duration of the shock and greatly reduce the pain.

Its also normal to experience
elevated heart rate & blood pressure. None of these, according to any
sensible definition, constitute serious injury.

Permanently elevated heart rate and blood pressure certainly count as
serious injury. Even temporary elevation will be a serious complication
for people with certain pre-existing conditions.

for most it does not constitute any injury, let alone serious injury


Nor do Bruises. The
data is complete bunk.

The data (while questionable) are by no means bunk. They have elevated
the figures by including some types of injury that one might argue are
less serious. However it is also very clear that even if the figures
were an order of magnitude out, for what you consider to be a serious
injury,

clearly they're a good 2 orders of magnitude out for _any_ injury.

you still have more than adequate justification for fitting
RCDs, and at worst, comparable justification to that for fitting smoke
alarms.

A number of which are recoverable from. From memory, there was
something like 5k - 10k in the most serious categories

a little different to 2.5 million then!

You do understand that not *all* shocks result in broken bones or
cardiac arrest?

shaking head

The 2.5 million figure is the estimate of the number of mains voltage
shocks received by adults each year - not those enduring life changing
effects. Are you now being deliberately obtuse?

shocks yes, not serious injuries as you claim. It would be bizarre to call pointing out the massive difference obtuse


And to make that more precise, since shock protection measures
have greatly improved in the last 80 years, the actual figure
would be far higher, if their claim were true. You always need to
look at the source and assess the data. Its pretty obvious
they're a group promoting increase of electrical safety, and
pretty obvious that a lot of people mislead & even lie routinely
when they have an agenda to pursue.

I fully accept they have an agenda, and that they have over stated
the figures for serious injury by including less serious injuries
into the "serious" category.

However, Even if 10x out (which is unlikely)

I agree 10x is unlikely. 100-1000x is far more likely. ISTR an
estimate of 600x from a few years ago, but don't remember where it
came from.

Even 1000x would be one serious injury per day. The hospital treatment
stats I have seen in the past indicate the figure is well above that
however.

Still we should be able to resolve this question shortly:

http://www.rospa.com/home-safety/res...tion-database/

that would still be plenty of justification for the current
regulations on the use of RCDs.

I think we all agree RCDs in new installs are a good thing. What was
being debated is the merits of retrofitting, where the cost & time
involved are a good bit more.

There is not that much difference in cost between a new CU installation,
and a retrofit IME. The latter takes a little longer, but not
dramatically - only enough to label and disconnect the existing wiring.

The muddle continues I see.
When fitting a new CU, adding RCD protection costs a few tenners and takes maybe a few minutes of extra time connecting neutrals.
Retrofitting RCDs requires a new CU installing, costing more money & time.

If you haven't got it yet that I'm interested in deaths not injuries,
then there's no point us continuing.

I understand you have a narrow focus on deaths. That's fine by me. If
you are content to tolerate the far more typical outcome of an electric
shock, (i.e. pain and injury), rather than spend a couple of hundred
preventing / reducing the risk then by all means carry on.

I don't accept that assessment

However you then go on to give misleading advice to people contemplating
on fitting RCDs based on that very narrow viewpoint. For the vast
majority of people looking at retrofitting RCDs for the protection of
their families, the protection from death aspect is certainly a very
"nice to have" bonus, but since its also a very low likelihood
occurrence - its not a big part of the decision making process. The real
motivation for most will be the greatly enhanced protection from injury
and pain that matters more.

in your opinion.
I'd far rather escape a death scenario to live another day than escape a shock.

Well, you're free to show us fatality figures that support that. You
never have. All you've offered is junk stats that claim wild levels
of injuries. This is precisely one of the reasons such decisions are
so often made on mortality, not injury stats, the latter are far less
reliable.

Not much help when we are trying to prevent injury rather than mortality
though...

you, not we

I am confused since you talk about all these risks that are higher
priority, and yet don't seem to be able to state what any of them
are.

What makes you think that?

2010 mortality: 158k circulatory diseases 141k cancer & neoplasms 67k
respiratory diseases 25k digestive diseases 19k dementia & mental
disorders 18k nervous system diseases 17k accidents & injuries 12k
genitourinary diseases 8k senility 5k diabetes

You appreciate we are all going to die from something eventually?

I hope you have something more useful to say than the bleeding obvious

We are discussing protection from accidental injury in the home,

no, you are

not
long term lifestyle choices / genetic predispositions and eventual
outcomes on health.

indeed this has nothing to do with genetics

Now which of the above can you fix in the home for a couple of hundred
quid?

As I've said before in this thread, the general concensus among experts is that 50% of deaths due to heart disease & cancer, ie 149,500 deaths each year, can be prevented by eating properly, not smoking and getting a little exercise. A couple of hundred quid covers that.

If you'd rather spend your £200 on avoiding an unknown small number of injuries each year that's your call. But don't expect me to say its a good choice. As I've said before.


I'm beginning to think no reason will come forth from you on this. If it doesn't I'll call it a day on this thread.


NT

wrote in message
...
On Friday, 3 July 2015 01:30:27 UTC+1, John Rumm wrote:
On 30/06/2015 22:11, nt wrote:
On Tuesday, 30 June 2015 16:21:45 UTC+1, John Rumm wrote:

What has the situation in the past got to do with recommendations
one would make now?

how ever else do you propose to assess what difference smoke alarms
have made?

Not by making wild claims of huge reductions in death rate and falsely
attributing that solely to smoke alarms, that is for sure. As Robin
pointed out, peak death occurred at a time when alarms were already well
established, and the recent falls in death rate do not correlate well
with the numbers of installed alarms. The data point to a much deeper
and more nuanced relationship.

Sure, I accept that data needs improving. Are you able to offer better
figures?

(you do realise that people also install smoke alarms for reasons in
addition to saving their lives? Or is this another case where you house
going up is smoke is of no concern, just that you don't die in the
process?)

ok, I accept you're not focussed on the biggest risks, and determined to
be silly.

'People receiving a mains voltage electric shock per year (15+):
2.5 million* Of whom received a serious injury: 350,000**'

Did you read the ** footnote?

yes... did you have a point?

You are claiming that their figures are implausible,

correct. it plainly is.

without apparently
taking into account their definition of serious injury. The footnote
goes some way to explain why the number is so high.

the footnotes explain why the claims are so ridiculous. I have explained
this before. There is patently no basis for your claim they've been
overlooked.

If that is correct, we would have, with average life expectancy
apx 80, 80x350,000 people in the uk who have been seriously
injured by

The figures are for those over 15 anyway, and if including those
who are 80 now, they would predate modern wiring practices.

yes...

So your sums are nonsense as well.

no, they're just rough ballpark which is enough to make the point. Feel
free to offer better figures if you have them.


You are also assuming that those shocked each year are unique -
when in reality some adults will be far more likely to receive a
shock than others. You will have many "serial offenders" here.

I don't recall making that assumption

the "80x350,000 people" sum was a bit of a give away.

if you want to calculate it more precisely, despite the huge changes in
wiring safety over the years, you're free to provide the necessary figures
and calculate it. A ballpark is all it takes to make the relevant point.

shock. That's 28 million! The most basic sanity check shows that
to be wildly unrealistic.

How many people have you met who claim to have *never* received an
electrical shock?

can't say I've asked. Why would I?

Many would meet the "serious" injury threshold set out
in the footnote.

which is not, in any sensible definition, serious injury


No, it shows you did not read the footnote. Their definition of
serious injury :

**Based on a survey of 4,032 adults in Great Britain aged 15+ who
have personally experienced an electric shock that resulted in
injury while at home or in the garden in the past twelve months
including all those who experienced one or more of the following
injuries: Severe pain, Skin burn without scarring, Bruising from a
fall or severe muscular contraction, Temporary blindness, Heartbeat
disturbance, Persistent pain or numbness, Higher blood pressure,
Skin burn with scarring, Broken bone(s), Difficulty breathing.'

At the risk of stating the utterly obvious, more or less all mains
shocks involve considerable pain.

Indeed. That is also part of the justification for using RCDs - they
limit the duration of the shock and greatly reduce the pain.

Its also normal to experience
elevated heart rate & blood pressure. None of these, according to any
sensible definition, constitute serious injury.

Permanently elevated heart rate and blood pressure certainly count as
serious injury. Even temporary elevation will be a serious complication
for people with certain pre-existing conditions.

for most it does not constitute any injury, let alone serious injury


Nor do Bruises. The
data is complete bunk.

The data (while questionable) are by no means bunk. They have elevated
the figures by including some types of injury that one might argue are
less serious. However it is also very clear that even if the figures
were an order of magnitude out, for what you consider to be a serious
injury,

clearly they're a good 2 orders of magnitude out for _any_ injury.

you still have more than adequate justification for fitting
RCDs, and at worst, comparable justification to that for fitting smoke
alarms.

A number of which are recoverable from. From memory, there was
something like 5k - 10k in the most serious categories

a little different to 2.5 million then!

You do understand that not *all* shocks result in broken bones or
cardiac arrest?

shaking head

The 2.5 million figure is the estimate of the number of mains voltage
shocks received by adults each year - not those enduring life changing
effects. Are you now being deliberately obtuse?

shocks yes, not serious injuries as you claim. It would be bizarre to call
pointing out the massive difference obtuse


And to make that more precise, since shock protection measures
have greatly improved in the last 80 years, the actual figure
would be far higher, if their claim were true. You always need to
look at the source and assess the data. Its pretty obvious
they're a group promoting increase of electrical safety, and
pretty obvious that a lot of people mislead & even lie routinely
when they have an agenda to pursue.

I fully accept they have an agenda, and that they have over stated
the figures for serious injury by including less serious injuries
into the "serious" category.

However, Even if 10x out (which is unlikely)

I agree 10x is unlikely. 100-1000x is far more likely. ISTR an
estimate of 600x from a few years ago, but don't remember where it
came from.

Even 1000x would be one serious injury per day. The hospital treatment
stats I have seen in the past indicate the figure is well above that
however.

Still we should be able to resolve this question shortly:

http://www.rospa.com/home-safety/res...tion-database/

that would still be plenty of justification for the current
regulations on the use of RCDs.

I think we all agree RCDs in new installs are a good thing. What was
being debated is the merits of retrofitting, where the cost & time
involved are a good bit more.

There is not that much difference in cost between a new CU installation,
and a retrofit IME. The latter takes a little longer, but not
dramatically - only enough to label and disconnect the existing wiring.

The muddle continues I see.
When fitting a new CU, adding RCD protection costs a few tenners and takes
maybe a few minutes of extra time connecting neutrals.
Retrofitting RCDs requires a new CU installing, costing more money & time.

If you haven't got it yet that I'm interested in deaths not injuries,
then there's no point us continuing.

I understand you have a narrow focus on deaths. That's fine by me. If
you are content to tolerate the far more typical outcome of an electric
shock, (i.e. pain and injury), rather than spend a couple of hundred
preventing / reducing the risk then by all means carry on.

I don't accept that assessment

However you then go on to give misleading advice to people contemplating
on fitting RCDs based on that very narrow viewpoint. For the vast
majority of people looking at retrofitting RCDs for the protection of
their families, the protection from death aspect is certainly a very
"nice to have" bonus, but since its also a very low likelihood
occurrence - its not a big part of the decision making process. The real
motivation for most will be the greatly enhanced protection from injury
and pain that matters more.

in your opinion.
I'd far rather escape a death scenario to live another day than escape a
shock.

Well, you're free to show us fatality figures that support that. You
never have. All you've offered is junk stats that claim wild levels
of injuries. This is precisely one of the reasons such decisions are
so often made on mortality, not injury stats, the latter are far less
reliable.

Not much help when we are trying to prevent injury rather than mortality
though...

you, not we

I am confused since you talk about all these risks that are higher
priority, and yet don't seem to be able to state what any of them
are.

What makes you think that?

2010 mortality: 158k circulatory diseases 141k cancer & neoplasms 67k
respiratory diseases 25k digestive diseases 19k dementia & mental
disorders 18k nervous system diseases 17k accidents & injuries 12k
genitourinary diseases 8k senility 5k diabetes

You appreciate we are all going to die from something eventually?

I hope you have something more useful to say than the bleeding obvious

We are discussing protection from accidental injury in the home,

no, you are

not
long term lifestyle choices / genetic predispositions and eventual
outcomes on health.

indeed this has nothing to do with genetics

Now which of the above can you fix in the home for a couple of hundred
quid?

As I've said before in this thread, the general concensus among experts is
that 50% of deaths due to heart disease & cancer, ie 149,500 deaths each
year, can be prevented by eating properly, not smoking and getting a
little exercise.

That is very arguable indeed given that you have to die of something
and you are still likely to die of either heart disease or cancer. It would
be more accurate to say that you may well be able to delay dying of
either of those since you will likely die of one or the other eventually.

A couple of hundred quid covers that.

That is very arguable too.

If you'd rather spend your £200 on avoiding an unknown small number
of injuries each year that's your call. But don't expect me to say its a
good choice.

It makes more sense to do both.

As I've said before.

I'm beginning to think no reason will come forth from
you on this. If it doesn't I'll call it a day on this thread.

On Sunday, 5 July 2015 00:11:44 UTC+1, ratsack wrote:
nt wrote in message
...
On Friday, 3 July 2015 01:30:27 UTC+1, John Rumm wrote:

Now which of the above can you fix in the home for a couple of hundred
quid?

As I've said before in this thread, the general concensus among experts is
that 50% of deaths due to heart disease & cancer, ie 149,500 deaths each
year, can be prevented by eating properly, not smoking and getting a
little exercise.

That is very arguable indeed given that you have to die of something
and you are still likely to die of either heart disease or cancer. It would
be more accurate to say that you may well be able to delay dying of
either of those since you will likely die of one or the other eventually.

ijcba

A couple of hundred quid covers that.

That is very arguable too.

of course there are ways yuo can waste money, doing the right things is cheap.

If you'd rather spend your �200 on avoiding an unknown small number
of injuries each year that's your call. But don't expect me to say its a
good choice.

It makes more sense to do both.

It makes more sense to put your risks in order and tackle the ones that are largest and you can have most effect on. RCDs are a drop in the ocean.


NT

wrote in message
...


It makes more sense to put your risks in order and tackle the ones that
are largest and you can have most effect on. RCDs are a drop in the
ocean.



So what are you going to spend your money on then?

Talking ******** is free and my last reply to you was to go and ****
yourself. I suggest thet you go and do it.


--
Adam

On Sunday, 5 July 2015 18:17:11 UTC+1, ARW wrote:
nt wrote in message
...

It makes more sense to put your risks in order and tackle the ones that
are largest and you can have most effect on. RCDs are a drop in the
ocean.

So what are you going to spend your money on then?

Talking ******** is free and my last reply to you was to go and ****
yourself. I suggest thet you go and do it.

useful as always


NT

wrote in message
...
On Sunday, 5 July 2015 18:17:11 UTC+1, ARW wrote:
nt wrote in message
...

It makes more sense to put your risks in order and tackle the ones that
are largest and you can have most effect on. RCDs are a drop in the
ocean.

So what are you going to spend your money on then?

Talking ******** is free and my last reply to you was to go and ****
yourself. I suggest thet you go and do it.

useful as always



And honest.

--
Adam

In message , ARW
writes
wrote in message
...


It makes more sense to put your risks in order and tackle the ones
that are largest and you can have most effect on. RCDs are a drop
in the ocean.



So what are you going to spend your money on then?


I was going to sit down and rate my risks, but I've spent so long
reading this argument that I'm just about to peg it.......
--
Chris French

wrote in message
...
On Sunday, 5 July 2015 00:11:44 UTC+1, ratsack wrote:
nt wrote in message
...
On Friday, 3 July 2015 01:30:27 UTC+1, John Rumm wrote:

Now which of the above can you fix in the home for a couple of hundred
quid?

As I've said before in this thread, the general concensus among experts
is
that 50% of deaths due to heart disease & cancer, ie 149,500 deaths
each
year, can be prevented by eating properly, not smoking and getting a
little exercise.

That is very arguable indeed given that you have to die of something
and you are still likely to die of either heart disease or cancer. It
would
be more accurate to say that you may well be able to delay dying of
either of those since you will likely die of one or the other eventually.

ijcba

A couple of hundred quid covers that.

That is very arguable too.

of course there are ways yuo can waste money, doing the right things is
cheap.

It is very arguable indeed that spending a couple of hundred quid
would eliminate half the deaths from due to heart disease & cancer.

If you'd rather spend your �200 on avoiding an unknown small number
of injuries each year that's your call. But don't expect me to say its
a
good choice.

It makes more sense to do both.

It makes more sense to put your risks in order and tackle
the ones that are largest and you can have most effect on.

No, it makes more sense to eliminate all risks that you
can eliminate for that sort of relatively small cost.

It clearly isn't feasible to have just single story houses
and no stairs anywhere, but clearly doesnt cost much
to mandate RCDs over the life of the property.

RCDs are a drop in the ocean.

But still worth doing, particularly worth mandating for new work.

On 04/07/2015 22:57, wrote:

Not by making wild claims of huge reductions in death rate and
falsely attributing that solely to smoke alarms, that is for sure.
As Robin pointed out, peak death occurred at a time when alarms
were already well established, and the recent falls in death rate
do not correlate well with the numbers of installed alarms. The
data point to a much deeper and more nuanced relationship.

Sure, I accept that data needs improving. Are you able to offer
better figures?

What I posted were the best I have found on the fire stats so far.

(you do realise that people also install smoke alarms for reasons
in addition to saving their lives? Or is this another case where
you house going up is smoke is of no concern, just that you don't
die in the process?)

ok, I accept you're not focussed on the biggest risks, and determined
to be silly.

You define "big risk" very narrowly as "most likely to kill you". This
is an absurdly narrow definition of risk that has potential to greatly
distort and misinform.

Take an example... you are a bomb disposal operative. Someone says to you:

Here, we have developed a new mine protection suit, its so good, we have
tested it, and shown that in the event of a mine strike, you have only a
0.001% chance of being killed. So why don't you wander off into that
minefield?

Now if we apply your logic, that's fine - wade right in there, is only a
1 in 100,000 chance of being killed - not even worth worrying about -
more risky crossing a road.

However your narrow focus has stopped you asking the relevant questions.
Like "what are the chances of being hit in the first place?" Well past
experience shows that 25% of operators were blown up who did enter.
Still want to go in?

How many were seriously injured? 50%.

What kind of injuries? We only count loss of two or more limbs as
"serious".

Still keen? - still only a 1 in 10k chance of being killed...

How many people have you met who claim to have *never* received an
electrical shock?

can't say I've asked. Why would I?

Many would meet the "serious" injury threshold set out in the
footnote.

which is not, in any sensible definition, serious injury

Not *all* of them sure, but some of them, very clearly are.

A number of which are recoverable from. From memory, there was
something like 5k - 10k in the most serious categories

a little different to 2.5 million then!

You do understand that not *all* shocks result in broken bones or
cardiac arrest?

shaking head

Its a simple concept - try harder.

The 2.5 million figure is the estimate of the number of mains
voltage shocks received by adults each year - not those enduring
life changing effects. Are you now being deliberately obtuse?

shocks yes, not serious injuries as you claim.

Do you need subtitles for the hard of comprehending?

Try this; Millions shocked, tens of thousands hurt badly enough to need
hospital treatment. Thousands left with permanent effects.

How much do you think each of those hospital visits cost? Bet even the
most minor is many times the price of a new CU.

When fitting a new CU, adding RCD
protection costs a few tenners

So you get the CU and MCBs free then on new installs? Let's have the
name of your wholesaler?

and takes maybe a few minutes of extra
time connecting neutrals. Retrofitting RCDs requires a new CU
installing, costing more money & time.

So new fit costs

1 CU + MCBs + RCDs + Time

Retrofit costs

1 CU + MCBs + RCDs + a little bit more time

Extra £50 perhaps?

in your opinion. I'd far rather escape a death scenario to live
another day than escape a shock.

I would rather do both.

Not much help when we are trying to prevent injury rather than
mortality though...

you, not we

Who is "we"? Take a vote...

2010 mortality: 158k circulatory diseases 141k cancer & neoplasms
67k respiratory diseases 25k digestive diseases 19k dementia &
mental disorders 18k nervous system diseases 17k accidents &
injuries 12k genitourinary diseases 8k senility 5k diabetes

You appreciate we are all going to die from something eventually?

I hope you have something more useful to say than the bleeding
obvious

We are discussing protection from accidental injury in the home,

no, you are

And I suspect a few others...

still I am done now.

not long term lifestyle choices / genetic predispositions and
eventual outcomes on health.

indeed this has nothing to do with genetics

158k circulatory diseases - nothing to do with genetics?

You may find the medical profession have different views.

I'm beginning to think no reason will come forth from you on this. If
it doesn't I'll call it a day on this thread.

I have...


--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/