In article <1qeftw3.1pmhnptl41w7eN%liz@poppyrecords.invalid.invalid>,
Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:
> charles <charles@candehope.me.uk> wrote:

> > In article <1qefm06.m4ixt41btb4s4N%liz@poppyrecords.invalid.invalid>,
> > Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:
> > > charles <charles@candehope.me.uk> wrote:
> >
> > > [...]
> > > > at BBC TV Centre, if you connected a set of headphones across the ststion
> > > > 50v battery, you couuld hear The Light Programme from Brookmans Park.
> >
> > > Only for a few seconds, I suppose - then your ears began to cook.
> >
> >
> >
> >
> > > 50v across 600 ohms = 4 watts.
> >
> > but, if you had a capacitor in the path, there'd be no DC flow.

> Nobody mentioned one.

True, but who'd be silly enough to put a set of cans directly across a 50v
battery

--
from KT24 in Surrey, England - sent from my RISC OS 4té
"I'd rather die of exhaustion than die of boredom" Thomas Carlyle

On 25/07/2023 19:30, charles wrote:
> In article <1qeftw3.1pmhnptl41w7eN%liz@poppyrecords.invalid.invalid>,
> Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:
>> charles <charles@candehope.me.uk> wrote:
>>> In article <1qefm06.m4ixt41btb4s4N%liz@poppyrecords.invalid.invalid>,
>>> Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:
>>>> charles <charles@candehope.me.uk> wrote:
>>>
>>>> [...]
>>>>> at BBC TV Centre, if you connected a set of headphones across the ststion
>>>>> 50v battery, you couuld hear The Light Programme from Brookmans Park.
>>>
>>>> Only for a few seconds, I suppose - then your ears began to cook.

>>>> 50v across 600 ohms = 4 watts.
>>>
>>> but, if you had a capacitor in the path, there'd be no DC flow.
>
>> Nobody mentioned one.
>
>
> True, but who'd be silly enough to put a set of cans directly across a 50v
> battery

I don't see the problem if they are high impedance.

--
Max Demian

On 25/07/2023 19:35, Max Demian wrote:
> On 25/07/2023 19:30, charles wrote:

>> True, but who'd be silly enough to put a set of cans directly across a
>> 50v
>> battery
>
> I don't see the problem if they are high impedance.
>
Piezo phones might work, as they are pretty much open circuit at DC, but
any magnetic drive type would have the transducers stuck fast at one end
of their travel by the DC.

--
Tciao for Now!

John.

Max Demian <max_demian@bigfoot.com> wrote:

> On 25/07/2023 19:30, charles wrote:
> > In article <1qeftw3.1pmhnptl41w7eN%liz@poppyrecords.invalid.invalid>,
> > Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:
> >> charles <charles@candehope.me.uk> wrote:
> >>> In article <1qefm06.m4ixt41btb4s4N%liz@poppyrecords.invalid.invalid>,
> >>> Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:
> >>>> charles <charles@candehope.me.uk> wrote:
> >>>
> >>>> [...]
> >>>>> at BBC TV Centre, if you connected a set of headphones across the
> >>>>> ststion 50v battery, you couuld hear The Light Programme from
> >>>>> Brookmans Park.
> >>>
> >>>> Only for a few seconds, I suppose - then your ears began to cook.
>
> >>>> 50v across 600 ohms = 4 watts.
> >>>
> >>> but, if you had a capacitor in the path, there'd be no DC flow.
> >
> >> Nobody mentioned one.
> >
> >
> > True, but who'd be silly enough to put a set of cans directly across a 50v
> > battery
>
> I don't see the problem if they are high impedance.

" at BBC TV Centre, if you connected a set of headphones across ..."

By then I would have thought most of the BBC headphones were the 600-ohm
STC type.

--
~ Liz Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

charles <charles@candehope.me.uk> wrote:

> In article <1qeftw3.1pmhnptl41w7eN%liz@poppyrecords.invalid.invalid>,
> Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:
> > charles <charles@candehope.me.uk> wrote:
>
> > > In article <1qefm06.m4ixt41btb4s4N%liz@poppyrecords.invalid.invalid>,
> > > Liz Tuddenham <liz@poppyrecords.invalid.invalid> wrote:
> > > > charles <charles@candehope.me.uk> wrote:
> > >
> > > > [...]
> > > > > at BBC TV Centre, if you connected a set of headphones across the
> > > > > ststion 50v battery, you couuld hear The Light Programme from
> > > > > Brookmans Park.
> > >
> > > > Only for a few seconds, I suppose - then your ears began to cook.
> > >
> > >
> > >
> > >
> > > > 50v across 600 ohms = 4 watts.
> > >
> > > but, if you had a capacitor in the path, there'd be no DC flow.
>
> > Nobody mentioned one.
>
>
> True, but who'd be silly enough to put a set of cans directly across a 50v
> battery

Well, it lookd as though that was what you were suggesting. :-)

--
~ Liz Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

On 25/07/2023 08:47, Mark Carver wrote:
> When HTV built their new studio centre at Culverhouse Cross in 1984, it
> was only a mile or so from Wenvoe. The RF levels from Wenvoe's Band I
> transmitter on the site were were so high, they had to build the
> technical areas in Faraday Cages.  Of course, Band I TV ceased in
> January 1985, so it wasn't required for very long.

I was told some time ago that Marks and Spencers had to spend a lot on
protecting their store near Lisnagarvey from the effects of RF.

On 25/07/2023 09:07, Woody wrote:
> Many people do not realise that Fylingdales and its associates work in
> the 420-450MHz band*: car keys used to use 433.92MHz (right in the
> middle of the 70cms amateur radio band of 430-440MHz) but many now use
> frequencies in the 860MHz area.
>
> Fylingdales was not so much of a problem. When the emergency services
> started using Airwave at 380/390MHz and digital the number of calls to
> the AA from drivers unable to get into their cars at Heathrow
> sky-rocketed. The aerials were placed on the roof of the car parks to
> give better coverage for car theft but it seemed to occur to no-one that
> the increased noise floor could affect keyless car entry!

I asked at Fylingdales what frequency it operated on and was told it was
secret! Obviously never heard of scanners or spectrum analysers.

With those levels of RF, the frequency is probably irrelevant with most
receivers.

There used to be remote car keys operating on a lot of different
frequencies (one of our vehicles at work had an illegal one!). But
probably not a problem now that most are factory fitted.

On 25/07/2023 10:15, charles wrote:
> at BBC TV Centre, if you connected a set of headphones across the ststion
> 50v battery, you couuld hear The Light Programme from Brookmans Park.

At Criggion you could 'hear' the transmissions inside the coil room
without any receiver or headphones!

MB <MB@nospam.net> wrote:

> On 25/07/2023 08:47, Mark Carver wrote:
> > When HTV built their new studio centre at Culverhouse Cross in 1984, it
> > was only a mile or so from Wenvoe. The RF levels from Wenvoe's Band I
> > transmitter on the site were were so high, they had to build the
> > technical areas in Faraday Cages.  Of course, Band I TV ceased in
> > January 1985, so it wasn't required for very long.
>
>
> I was told some time ago that Marks and Spencers had to spend a lot on
> protecting their store near Lisnagarvey from the effects of RF.

What is the legal situation if equipment in an existing building is
affected by a newly-built transmitter?

A long time ago (when I had a G8 licence) my station was 'raided' by a
P.O. Wireless Inspector. There had been complaints from a neighbour
about interference on his rented T.V. My transmitter was within spec.
and his set was missing some screening, so in that particular case the
problem was his.

If I had been a broadcaster putting out a huge, but legal, signal and
nearby buildings were saturated, would I be legally responsible for
mitigating the nuisance?

--
~ Liz Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

On 26/07/2023 10:02, Liz Tuddenham wrote:
> If I had been a broadcaster putting out a huge, but legal, signal and
> nearby buildings were saturated, would I be legally responsible for
> mitigating the nuisance?

Sure someone knows better but I think on shared transmitter sites then
it is the responsibility of the last person to go on the site to provide
filtering.

So I think that if you decide to use a site and your own equipment
cannot cope with quite legal clean transmissions then it is your own
problem.

Though if it is because of a transmitter producing out of band
interference then it would be probably be their responsibility to make
their transmitter comply with regulations first.

"MB" <MB@nospam.net> wrote in message news:u9qfq8$1e4r0$2@dont-email.me...
> On 25/07/2023 09:07, Woody wrote:
>> Many people do not realise that Fylingdales and its associates work in
>> the 420-450MHz band*: car keys used to use 433.92MHz (right in the
>> middle of the 70cms amateur radio band of 430-440MHz) but many now use
>> frequencies in the 860MHz area.
>>
>> Fylingdales was not so much of a problem. When the emergency services
>> started using Airwave at 380/390MHz and digital the number of calls to
>> the AA from drivers unable to get into their cars at Heathrow
>> sky-rocketed. The aerials were placed on the roof of the car parks to
>> give better coverage for car theft but it seemed to occur to no-one that
>> the increased noise floor could affect keyless car entry!
>
>
> I asked at Fylingdales what frequency it operated on and was told it was
> secret! Obviously never heard of scanners or spectrum analysers.
>
> With those levels of RF, the frequency is probably irrelevant with most
> receivers.
>
> There used to be remote car keys operating on a lot of different
> frequencies (one of our vehicles at work had an illegal one!). But
> probably not a problem now that most are factory fitted.

The real problem is those cars that have no mechanical keyhole (or else one
that needs tools to access in an emergency), where you can only use the
remote. I'm used to one of my car keys (I keep it as the spare) not
operating the central locking (yes I've replaced its battery!) and so having
to lock/unlock the doors the old-fashioned way when Ii take the car to the
garage to be serviced. And I warn them, though I imagine they are used to
central locking failing for whatever reason and know how to use the key
blade.

And if the RF is so strong that it even affects the key-ECU comms for the
immobiliser, then you are totally stuffed. I presume the only way around
that is to tow the car far enough away that the key and immobiliser can talk
and so negotiate to enable the engine.

In article <u9qtdm$1fit9$1@dont-email.me>, NY <me@privacy.invalid>
scribeth thus
>"MB" <MB@nospam.net> wrote in message news:u9qfq8$1e4r0$2@dont-email.me...
>> On 25/07/2023 09:07, Woody wrote:
>>> Many people do not realise that Fylingdales and its associates work in
>>> the 420-450MHz band*: car keys used to use 433.92MHz (right in the
>>> middle of the 70cms amateur radio band of 430-440MHz) but many now use
>>> frequencies in the 860MHz area.
>>>
>>> Fylingdales was not so much of a problem. When the emergency services
>>> started using Airwave at 380/390MHz and digital the number of calls to
>>> the AA from drivers unable to get into their cars at Heathrow
>>> sky-rocketed. The aerials were placed on the roof of the car parks to
>>> give better coverage for car theft but it seemed to occur to no-one that
>>> the increased noise floor could affect keyless car entry!
>>
>>
>> I asked at Fylingdales what frequency it operated on and was told it was
>> secret! Obviously never heard of scanners or spectrum analysers.
>>
>> With those levels of RF, the frequency is probably irrelevant with most
>> receivers.
>>
>> There used to be remote car keys operating on a lot of different
>> frequencies (one of our vehicles at work had an illegal one!). But
>> probably not a problem now that most are factory fitted.
>
>The real problem is those cars that have no mechanical keyhole (or else one
>that needs tools to access in an emergency), where you can only use the
>remote. I'm used to one of my car keys (I keep it as the spare) not
>operating the central locking (yes I've replaced its battery!) and so having
>to lock/unlock the doors the old-fashioned way when Ii take the car to the
>garage to be serviced. And I warn them, though I imagine they are used to
>central locking failing for whatever reason and know how to use the key
>blade.
>
>And if the RF is so strong that it even affects the key-ECU comms for the
>immobiliser, then you are totally stuffed. I presume the only way around
>that is to tow the car far enough away that the key and immobiliser can talk
>and so negotiate to enable the engine.
>

Begs the question what do the staff at Fylingdales use for transport?,

push bikes?...

--
Tony Sayer

Man is least himself when he talks in his own person.

Give him a keyboard, and he will reveal himself.

On 26/07/2023 10:02, Liz Tuddenham wrote:
>
> What is the legal situation if equipment in an existing building is
> affected by a newly-built transmitter?
>
> There's this little story from the era the BBC had an AM transmitter sited at Sutton Coldfield

http://txfeatures.mb21.co.uk/coldfield/11.shtml

In message <tMg4NvA6ZSwkFwui@bancom.co.uk> at Wed, 26 Jul 2023 14:58:18,
tony sayer <tony@bancom.co.uk> writes
[]
>Begs the question what do the staff at Fylingdales use for transport?,
>
>push bikes?...
>
>
Not the same question, but I remember hearing/seeing somewhere that at
certain oil (gas?) refinery sites, conventional vehicles were not
allowed, especially diesel ones, because the air was sufficiently
flammable that even if you turned the ignition off, the engine would
race, to the extent of flames coming out of the exhaust; vehicles for
use on the site had to be modified in some way.
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

By most scientific estimates sustained, useful fusion is ten years in
the future - and will be ten years in the future for the next fifty
years or more. - "Hamadryad", ~2016-4-4

tony sayer <tony@bancom.co.uk> wrote:

> In article <u9qtdm$1fit9$1@dont-email.me>, NY <me@privacy.invalid>
> scribeth thus
> >"MB" <MB@nospam.net> wrote in message news:u9qfq8$1e4r0$2@dont-email.me...
> >> On 25/07/2023 09:07, Woody wrote:
> >>> Many people do not realise that Fylingdales and its associates work in
> >>> the 420-450MHz band*: car keys used to use 433.92MHz (right in the
> >>> middle of the 70cms amateur radio band of 430-440MHz) but many now use
> >>> frequencies in the 860MHz area.
> >>>
> >>> Fylingdales was not so much of a problem. When the emergency services
> >>> started using Airwave at 380/390MHz and digital the number of calls to
> >>> the AA from drivers unable to get into their cars at Heathrow
> >>> sky-rocketed. The aerials were placed on the roof of the car parks to
> >>> give better coverage for car theft but it seemed to occur to no-one that
> >>> the increased noise floor could affect keyless car entry!
> >>
> >>
> >> I asked at Fylingdales what frequency it operated on and was told it was
> >> secret! Obviously never heard of scanners or spectrum analysers.
> >>
> >> With those levels of RF, the frequency is probably irrelevant with most
> >> receivers.
> >>
> >> There used to be remote car keys operating on a lot of different
> >> frequencies (one of our vehicles at work had an illegal one!). But
> >> probably not a problem now that most are factory fitted.
> >
> >The real problem is those cars that have no mechanical keyhole (or else one
> >that needs tools to access in an emergency), where you can only use the
> >remote. I'm used to one of my car keys (I keep it as the spare) not
> >operating the central locking (yes I've replaced its battery!) and so having
> >to lock/unlock the doors the old-fashioned way when Ii take the car to the
> >garage to be serviced. And I warn them, though I imagine they are used to
> >central locking failing for whatever reason and know how to use the key
> >blade.
> >
> >And if the RF is so strong that it even affects the key-ECU comms for the
> >immobiliser, then you are totally stuffed. I presume the only way around
> >that is to tow the car far enough away that the key and immobiliser can talk
> >and so negotiate to enable the engine.
> >
>
> Begs the question what do the staff at Fylingdales use for transport?,
>
> push bikes?...

Good job they don't transmit on wavelengths around 2 metres, a half-wave
pushbike frame could give you some nasty R.F. burns.

--
~ Liz Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

"J. P. Gilliver" <G6JPG@255soft.uk> wrote in message
news:kukPjzebWVwkFw9J@255soft.uk...
> In message <tMg4NvA6ZSwkFwui@bancom.co.uk> at Wed, 26 Jul 2023 14:58:18,
> tony sayer <tony@bancom.co.uk> writes
> []
>>Begs the question what do the staff at Fylingdales use for transport?,
>>
>>push bikes?...
>>
>>
> Not the same question, but I remember hearing/seeing somewhere that at
> certain oil (gas?) refinery sites, conventional vehicles were not allowed,
> especially diesel ones, because the air was sufficiently flammable that
> even if you turned the ignition off, the engine would race, to the extent
> of flames coming out of the exhaust; vehicles for use on the site had to
> be modified in some way.

I saw a TV programme (maybe Michael Portillo's railway programme) where the
presenter was taken into an underground tunnel somewhere, and he was told
that the only cars that were allowed underground in the tunnels were diesel
ones, because petrol engines were too likely to generate a spark that could
ignite flammable fumes,

On 27/07/2023 11:17, NY wrote:
> "J. P. Gilliver" <G6JPG@255soft.uk> wrote in message
> news:kukPjzebWVwkFw9J@255soft.uk...
>> In message <tMg4NvA6ZSwkFwui@bancom.co.uk> at Wed, 26 Jul 2023
>> 14:58:18, tony sayer <tony@bancom.co.uk> writes
>> []
>>> Begs the question what do the staff at Fylingdales use for transport?,
>>>
>>> push bikes?...
>>>
>>>
>> Not the same question, but I remember hearing/seeing somewhere that at
>> certain oil (gas?) refinery sites, conventional vehicles were not
>> allowed, especially diesel ones, because the air was sufficiently
>> flammable that even if you turned the ignition off, the engine would
>> race, to the extent of flames coming out of the exhaust; vehicles for
>> use on the site had to be modified in some way.
>
> I saw a TV programme (maybe Michael Portillo's railway programme) where
> the presenter was taken into an underground tunnel somewhere, and he was
> told that the only cars that were allowed underground in the tunnels
> were diesel ones, because petrol engines were too likely to generate a
> spark that could ignite flammable fumes,

If they develop a leak, petrol is also far easier to ignite than diesel.

--
Tciao for Now!

John.

"John Williamson" <johnwilliamson@btinternet.com> wrote in message
news:kiev3qFbe6tU1@mid.individual.net...
> On 27/07/2023 11:17, NY wrote:
>> "J. P. Gilliver" <G6JPG@255soft.uk> wrote in message
>> news:kukPjzebWVwkFw9J@255soft.uk...
>>> In message <tMg4NvA6ZSwkFwui@bancom.co.uk> at Wed, 26 Jul 2023
>>> 14:58:18, tony sayer <tony@bancom.co.uk> writes
>>> []
>>>> Begs the question what do the staff at Fylingdales use for transport?,
>>>>
>>>> push bikes?...
>>>>
>>>>
>>> Not the same question, but I remember hearing/seeing somewhere that at
>>> certain oil (gas?) refinery sites, conventional vehicles were not
>>> allowed, especially diesel ones, because the air was sufficiently
>>> flammable that even if you turned the ignition off, the engine would
>>> race, to the extent of flames coming out of the exhaust; vehicles for
>>> use on the site had to be modified in some way.
>>
>> I saw a TV programme (maybe Michael Portillo's railway programme) where
>> the presenter was taken into an underground tunnel somewhere, and he was
>> told that the only cars that were allowed underground in the tunnels
>> were diesel ones, because petrol engines were too likely to generate a
>> spark that could ignite flammable fumes,
>
> If they develop a leak, petrol is also far easier to ignite than diesel.

Too right.

The first place I worked, as a summer job before going to university, was a
large open site with lots of grassy areas between buildings - it had been an
old airfield.

Everyone had to do fire safety testing as part of the induction process.

The fire safety guy had laid two shallow metal pans on the grass, about a
metre square and a centimetre or so deep. He poured a bit of petrol in one
of them. It was a hot sunny day so the petrol would have started to
evaporate. He lit a rag on a metal pole and brought it near the tray. The
petrol ignited when the torch was a metre or so away: the fumes ignited and
carried the ignition source back to the tray.

Once it had safely burned away, he repeated the process with diesel fuel. He
could not ignite it, even by bringing the torch so it was almost in contact
with the fuel, and as soon as he dipped it in, the flame was extinguished.

The only way he could ignite the diesel was to suck a bit up into a tube
with a narrow end, making a crude diesel injector. The tiny droplets that
emerged could be ignited with the torch, but even that didn't ignite the
rest of the fuel in the tray, just making a jet that went out as soon as the
torch was removed.

On 27/07/2023 11:17, NY wrote:
> I saw a TV programme (maybe Michael Portillo's railway programme) where the
> presenter was taken into an underground tunnel somewhere, and he was told
> that the only cars that were allowed underground in the tunnels were diesel
> ones, because petrol engines were too likely to generate a spark that could
> ignite flammable fumes,

That is quite common.

We had a contract at an underground power station which involved a drive
down a tunnel. Petrol vehicles were not allowed and any combustibles in
the vehicle had to be declared.

All vehicles were parked facing outwards with keys inside.

There was a tally board and in the event of an alarm you would be put in
vehicles and taken out. In the event of a high level alarm, you could
use any vehicle and GET OUT!

It would be interesting to know if battery vehicles are allowed, I was
told a few days ago of another one exploding and it being hushed up.

On 27/07/2023 12:13, MB wrote:

> It would be interesting to know if battery vehicles are allowed, I was
> told a few days ago of another one exploding and it being hushed up.
>
>
>
There is a ship carrying a number which was on fire near Amsterdam
recently (Yesterday?) and one crew member was killed while trying to put
the fire out,

--
Tciao for Now!

John.

In message <u9thki$1s0rm$1@dont-email.me> at Thu, 27 Jul 2023 11:41:38,
NY <me@privacy.invalid> writes
>"John Williamson" <johnwilliamson@btinternet.com> wrote in message
>news:kiev3qFbe6tU1@mid.individual.net...
>> On 27/07/2023 11:17, NY wrote:
>>> "J. P. Gilliver" <G6JPG@255soft.uk> wrote in message
>>> news:kukPjzebWVwkFw9J@255soft.uk...
>>>> In message <tMg4NvA6ZSwkFwui@bancom.co.uk> at Wed, 26 Jul 2023
>>>> 14:58:18, tony sayer <tony@bancom.co.uk> writes
>>>> []
>>>>> Begs the question what do the staff at Fylingdales use for transport?,
>>>>>
>>>>> push bikes?...
>>>>>
(Recent almost manic coverage of e-bike fires has obviously generated
the question in my mind of why we don't hear about such with EVs - and
why no-one was even raising the _question_ with the e-bike panic. One
could almost suspect government censorship ...)
>>>>>
>>>> Not the same question, but I remember hearing/seeing somewhere that at
>>>> certain oil (gas?) refinery sites, conventional vehicles were not
>>>> allowed, especially diesel ones, because the air was sufficiently
>>>> flammable that even if you turned the ignition off, the engine would
>>>> race, to the extent of flames coming out of the exhaust; vehicles for
>>>> use on the site had to be modified in some way.
>>>
>>> I saw a TV programme (maybe Michael Portillo's railway programme) where
>>> the presenter was taken into an underground tunnel somewhere, and he was
>>> told that the only cars that were allowed underground in the tunnels
>>> were diesel ones, because petrol engines were too likely to generate a
>>> spark that could ignite flammable fumes,

Though in a flammable atmosphere, Diesel ones are more likely to run
away.
>>
>> If they develop a leak, petrol is also far easier to ignite than diesel.
>
>Too right.
[Interesting story snipped]
I remember reading/hearing somewhere that during the war, there were
tanks with petrol engines and tanks with diesel engines (presumably
because of engine manufacturing capacity), and you were far more likely
to survive a fire in the latter. With the former known to the Germans as
"Tommy-cookers".
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

There's only so much you can do... with gravel.
- Charlie Dimmock, RT 2016/7/9-15

J. P. Gilliver <G6JPG@255soft.uk> wrote:

> In message <tMg4NvA6ZSwkFwui@bancom.co.uk> at Wed, 26 Jul 2023 14:58:18,
> tony sayer <tony@bancom.co.uk> writes
> []
> >Begs the question what do the staff at Fylingdales use for transport?,
> >
> >push bikes?...
> >
> >
> Not the same question, but I remember hearing/seeing somewhere that at
> certain oil (gas?) refinery sites, conventional vehicles were not
> allowed, especially diesel ones, because the air was sufficiently
> flammable that even if you turned the ignition off, the engine would
> race, to the extent of flames coming out of the exhaust; vehicles for
> use on the site had to be modified in some way.

Whilst Diesel is inherently safer than petrol in most circumstances,
diesel engines can run away uncontrollably if they suck fuel into the
air inlet. A failed oil seal in the turbo is the most likely cause and
the results can be frightening.

Boats with propane cooking arrangements are a particular risk because
the propane collects in the bilges and a runaway engine can tear a hole
in the bottom if it seizes when overspeeding. I believe it is mandatory
to have speed-operated strangler valves in the air intakes of all diesel
engines in seagoing boats.

--
~ Liz Tuddenham ~
(Remove the ".invalid"s and add ".co.uk" to reply)
www.poppyrecords.co.uk

In message <u9tjgf$1s521$1@dont-email.me> at Thu, 27 Jul 2023 12:13:20,
MB <MB@nospam.net> writes
>On 27/07/2023 11:17, NY wrote:
>> I saw a TV programme (maybe Michael Portillo's railway programme) where the
>> presenter was taken into an underground tunnel somewhere, and he was told
>> that the only cars that were allowed underground in the tunnels were diesel
>> ones, because petrol engines were too likely to generate a spark that could
>> ignite flammable fumes,
>
>
>
>That is quite common.
>
>We had a contract at an underground power station which involved a
>drive down a tunnel. Petrol vehicles were not allowed and any
>combustibles in the vehicle had to be declared.
>
>All vehicles were parked facing outwards with keys inside.

I think that would be Dinorwic (or is it -wig?) pumped storage plant in
a Welsh mountain - used for peak levelling; it pumps water from the
reservoir at the bottom to the one at the top when there is spare
capacity on the grid, and the pumps can be switched to generators at
times of peak demand, letting the water fall back down again to drive
them. They're quite proud of how few seconds the whole thing can be
reversed if unexpectedly needed. But should something break, the
chambers inside the mountain would fill with water _very_ fast, hence
the need for a swift escape.
>
>There was a tally board and in the event of an alarm you would be put
>in vehicles and taken out. In the event of a high level alarm, you
>could use any vehicle and GET OUT!
>
>It would be interesting to know if battery vehicles are allowed, I was
>told a few days ago of another one exploding and it being hushed up.
>
>
>
--
J. P. Gilliver. UMRA: 1960/<1985 MB++G()AL-IS-Ch++(p)Ar@T+H+Sh0!:`)DNAf

There's only so much you can do... with gravel.
- Charlie Dimmock, RT 2016/7/9-15

On 27/07/2023 12:13, MB wrote:

> It would be interesting to know if battery vehicles are allowed, I was
> told a few days ago of another one exploding and it being hushed up.
>
Many hybrid vehicles use the same battery technology. About once a week
I see a story of yet another bus igniting and the batteries exploding.
It closes the road for a while, and it gets resurfaced overnight.

I have personally seen it happen to a car on the M62, and every minute
or so, another battery would go pop with the resulting ball of hot gas.
That carriageway was closed for an hour or two, when I went past in the
way back, there was a melted patch, and the following morning, there was
a patch of fresh tarmac on the hard shoulder.

The fire brigades in the UK, and, presumably elsewhere, now have
approved procedures for dealing with the problem.

--
Tciao for Now!

John.

On 27/07/2023 16:12, J. P. Gilliver wrote:
> I think that would be Dinorwic (or is it -wig?) pumped storage plant in
> a Welsh mountain

No, more local.

If you go on the tour then just hope you do not have to use the
emergency exit! :-)