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.

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