"Nightjar" wrote in message
...
On 14/03/2013 13:04, Martin Brown wrote:
On 14/03/2013 11:21, Mark wrote:
On Wed, 13 Mar 2013 08:13:06 +0000, Martin Brown
wrote:

--snip--

Switching off lights after midnight is a clear electricity saving
provided that their contract allows it and is not a pay per stalk deal.

But is likely to result in an increase in crime and road accidents.
I'll bet they haven't costed this.

Fear of the dark is a serious problem. City dwellers confuse being
dazzled by the glare of strong directional lights with "good" lighting.
Shopping centre advertise their presence with a light dome and it works.

There is no evidence to suggest that turning off street lamps late at
night affects either crime rates or road accidents.

RoSPA do not agree with you:

http://www.rospa.com/roadsafety/advi...-lighting.aspx

The presence of lighting not only reduces the risk of traffic accidents,
but also their severity ...

In some locations, a reduction in lighting quality may not increase the
risk of an accident. However, there is the danger that an unconsidered
removal or reduction in quality could actually increase accidents and
their severity.

Colin Bignell


A very interesting reference document. It is now in my favourites. As to
driving in the dark, I think a lot depends on your age. I don't know if it
is a general physical degradation in your night time vision, or just a
perceived thing. What I do know is that I am a lot less comfortable now
driving in the dark, than I was 20 years ago. Asking among my friends of a
similar age to me, I find that most share this feeling. Which concerns me a
little, because the chances are that these lighting change and reduction
schemes, are being designed by twenty or thirty-somethings with a shiny
degree and 'young' vision, and no understanding of the needs of older people
when driving at night. A couple of weeks ago, we had some really thick fog
around here - the thickest that I had seen in some years. The existing low
and high pressure sodium lamps that we had all over the village before they
started on the change to white LEDs, saw through this fog without too much
trouble, which was one of the original - and valid - claims for sodium
vapour lighting when it was first introduced. It will be interesting to see
how these white LED lamps perform in similar conditions.

Another of the claims by the council when the leafleted us, was that night
time colour vision would be improved because of the better CRI of the LEDs.
This has always been a bit of an issue on a Thursday night because it was
hard to see what colour bin the smart-arse across the road who always gets
it right, had put out. Well, tonight, I drove round the other end of the
road where they have the new lights installed and working, expecting to see
all the bright green bins out. Instead, setting aside the fact that the new
lights dazzled me, making it hard to see anything through the retina
'burns', the colour of the bins was actually no clearer than it was under
the sodiums ... :-\

Arfa