A school has just gone up in flames in my area. Usual photos of it burning
inside whilst water is put on the outside. Usual cries for sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what about a
simple array of pipes in the roof space with open nozzles. In the event of
a fire then the Fire Engine hooks up and dowses the fire from the inside
using the fixed nozzles - no need to enter the building. Notre Dame would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but has the
advantage of not being automatic and able to flood the building.

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it burning
inside whilst water is put on the outside. Usual cries for sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what about a
simple array of pipes in the roof space with open nozzles. In the event of
a fire then the Fire Engine hooks up and dowses the fire from the inside
using the fixed nozzles - no need to enter the building. Notre Dame would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but has the
advantage of not being automatic and able to flood the building.


Unlike a sprinkler system, which releases water only in the vicinity of
the fire, that would release water throughout the building. Fine if the
whole building is on fire, but it could result in unnecessary water
damage if the fire were only localised.

There are dry sprinkler systems. They contain compressed air or
nitrogen, but they still need a detector head to activate. That releases
the gas which, in turn, activates a valve that allows water to enter the
system.

--
Colin Bignell

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it burning
inside whilst water is put on the outside. Usual cries for sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what about a
simple array of pipes in the roof space with open nozzles. In the event of
a fire then the Fire Engine hooks up and dowses the fire from the inside
using the fixed nozzles - no need to enter the building. Notre Dame would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but has the
advantage of not being automatic and able to flood the building.


A type of automatic dry riser you mean?...

"Jim GM4 DHJ ..." wrote in
:

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it
burning inside whilst water is put on the outside. Usual cries for
sprinklers - but these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what
about a simple array of pipes in the roof space with open nozzles. In
the event of a fire then the Fire Engine hooks up and dowses the fire
from the inside using the fixed nozzles - no need to enter the
building. Notre Dame would have possibly been saved if such a simple
system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but
has the advantage of not being automatic and able to flood the
building.


A type of automatic dry riser you mean?...


As I understand it a dry riser usually just feeds hose points on upper
floors so they need firement to enter the building and use a safe
stairwell.

nightjar wrote in
:

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it
burning inside whilst water is put on the outside. Usual cries for
sprinklers - but these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what
about a simple array of pipes in the roof space with open nozzles. In
the event of a fire then the Fire Engine hooks up and dowses the fire
from the inside using the fixed nozzles - no need to enter the
building. Notre Dame would have possibly been saved if such a simple
system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but
has the advantage of not being automatic and able to flood the
building.


Unlike a sprinkler system, which releases water only in the vicinity
of the fire, that would release water throughout the building. Fine if
the whole building is on fire, but it could result in unnecessary
water damage if the fire were only localised.

There are dry sprinkler systems. They contain compressed air or
nitrogen, but they still need a detector head to activate. That
releases the gas which, in turn, activates a valve that allows water
to enter the system.


Good point - Perhaps with Zones - selected by the fire brigade.

On 04/10/2020 12:58, Chris Hogg wrote:
On Sun, 4 Oct 2020 12:34:51 +0100, nightjar wrote:

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it burning
inside whilst water is put on the outside. Usual cries for sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what about a
simple array of pipes in the roof space with open nozzles. In the event of
a fire then the Fire Engine hooks up and dowses the fire from the inside
using the fixed nozzles - no need to enter the building. Notre Dame would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but has the
advantage of not being automatic and able to flood the building.


Unlike a sprinkler system, which releases water only in the vicinity of
the fire, that would release water throughout the building. Fine if the
whole building is on fire, but it could result in unnecessary water
damage if the fire were only localised.

There are dry sprinkler systems. They contain compressed air or
nitrogen, but they still need a detector head to activate. That releases
the gas which, in turn, activates a valve that allows water to enter the
system.

IIRC large electrical installations such as large switch rooms in
basements etc have CO2 cylinders installed and ready to be discharged
in case of fire, thereby depriving the fire of oxygen but not
electrocuting anyone by throwing water around. But there's the danger
of suffocation if the system goes off and there's someone trapped
nearby.


I had an MRI scan recently, and the room had a very, very heavy steel
door that appeared air tight. I assume that was to protect the rest of
the building if the helium boiled?

On Sun, 04 Oct 2020 11:15:14 GMT, JohnP wrote:

A school has just gone up in flames in my area. Usual photos of it burning
inside whilst water is put on the outside. Usual cries for sprinklers - but
these can be vandalised and could cause problems.

Sprinkler heads which are recessed so flush with the ceiling are
commonly used if there is a problem with idiots smashing the more
common head. when triggered by localised heat the head extends and
emits a water spray. The head sometimes uses a heat initiated wax
motor so no power supply needed.

Any thoughts? It seems a compromise to a full sprinkler system but has the
advantage of not being automatic and able to flood the building.

Being automatic is a considerable advantage, with sprinklers the fire
is usually out or well contained before the fire service arrives.
Flooding a building is generally a really bad idea, the water damage
is often more expensive than the fire damage.

On Sun, 04 Oct 2020 13:44:58 +0100, GB wrote:

On 04/10/2020 12:58, Chris Hogg wrote:
On Sun, 4 Oct 2020 12:34:51 +0100, nightjar wrote:

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it
burning inside whilst water is put on the outside. Usual cries for
sprinklers - but these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what
about a simple array of pipes in the roof space with open nozzles. In
the event of a fire then the Fire Engine hooks up and dowses the fire
from the inside using the fixed nozzles - no need to enter the
building. Notre Dame would have possibly been saved if such a simple
system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but
has the advantage of not being automatic and able to flood the
building.


Unlike a sprinkler system, which releases water only in the vicinity
of the fire, that would release water throughout the building. Fine if
the whole building is on fire, but it could result in unnecessary
water damage if the fire were only localised.

There are dry sprinkler systems. They contain compressed air or
nitrogen, but they still need a detector head to activate. That
releases the gas which, in turn, activates a valve that allows water
to enter the system.

IIRC large electrical installations such as large switch rooms in
basements etc have CO2 cylinders installed and ready to be discharged
in case of fire, thereby depriving the fire of oxygen but not
electrocuting anyone by throwing water around. But there's the danger
of suffocation if the system goes off and there's someone trapped
nearby.


I had an MRI scan recently, and the room had a very, very heavy steel
door that appeared air tight. I assume that was to protect the rest of
the building if the helium boiled?

I don't think there is anything worse than squeaky voices, especially with
weather forecasters.

On 04/10/2020 13:44, GB wrote:

snip

I had an MRI scan recently, and the room had a very, very heavy steel
door that appeared air tight. I assume that was to protect the rest of
the building if the helium boiled?


If this was the door through which you entered it may have been just to
maintain RF shielding. They don't plan on the patient being left to
suffer if quenching leads to increased pressure in the scan room, or for
any window to the control room to blow out explosively.



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

On 04/10/2020 13:51, Peter Parry wrote:
On Sun, 04 Oct 2020 11:15:14 GMT, JohnP wrote:

A school has just gone up in flames in my area. Usual photos of it burning
inside whilst water is put on the outside. Usual cries for sprinklers - but
these can be vandalised and could cause problems.

Sprinkler heads which are recessed so flush with the ceiling are
commonly used if there is a problem with idiots smashing the more
common head. when triggered by localised heat the head extends and
emits a water spray. The head sometimes uses a heat initiated wax
motor so no power supply needed.

Any thoughts? It seems a compromise to a full sprinkler system but has the
advantage of not being automatic and able to flood the building.

Being automatic is a considerable advantage, with sprinklers the fire
is usually out or well contained before the fire service arrives.
Flooding a building is generally a really bad idea, the water damage
is often more expensive than the fire damage.



Presumably if the wax stopcock is remote from the sprinkler head it can
switch off once the temperature drops and so minimise damage?

On 04/10/2020 12:58, Chris Hogg wrote:
On Sun, 4 Oct 2020 12:34:51 +0100, nightjar wrote:

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it burning
inside whilst water is put on the outside. Usual cries for sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what about a
simple array of pipes in the roof space with open nozzles. In the event of
a fire then the Fire Engine hooks up and dowses the fire from the inside
using the fixed nozzles - no need to enter the building. Notre Dame would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but has the
advantage of not being automatic and able to flood the building.


Unlike a sprinkler system, which releases water only in the vicinity of
the fire, that would release water throughout the building. Fine if the
whole building is on fire, but it could result in unnecessary water
damage if the fire were only localised.

There are dry sprinkler systems. They contain compressed air or
nitrogen, but they still need a detector head to activate. That releases
the gas which, in turn, activates a valve that allows water to enter the
system.

IIRC large electrical installations such as large switch rooms in
basements etc have CO2 cylinders installed and ready to be discharged
in case of fire, thereby depriving the fire of oxygen but not
electrocuting anyone by throwing water around. But there's the danger
of suffocation if the system goes off and there's someone trapped
nearby.


I was an IT contractor at an insurabnce co in Croydon where the
door to the computer room on the top floor had two push buttons,
one to ring the bell to request entrance, and the other to set off
the Halon fire extinguishers.
This was actually activated twice during a 4 year period by people
who thought it was the door entrance button, despite being protected
by a sliding perspex cover and clearly marked.

On 04/10/2020 13:44, GB wrote:
On 04/10/2020 12:58, Chris Hogg wrote:
On Sun, 4 Oct 2020 12:34:51 +0100, nightjar wrote:

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it
burning
inside whilst water is put on the outside. Usual cries for
sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what
about a
simple array of pipes in the roof space with open nozzles. In the
event of
a fire then the Fire Engine hooks up and dowses the fire from the
inside
using the fixed nozzles - no need to enter the building. Notre Dame
would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but
has the
advantage of not being automatic and able to flood the building.


Unlike a sprinkler system, which releases water only in the vicinity of
the fire, that would release water throughout the building. Fine if the
whole building is on fire, but it could result in unnecessary water
damage if the fire were only localised.

There are dry sprinkler systems. They contain compressed air or
nitrogen, but they still need a detector head to activate. That releases
the gas which, in turn, activates a valve that allows water to enter the
system.

IIRC large electrical installations such as large switch rooms in
basements etc have CO2 cylinders installed and ready to be discharged
in case of fire, thereby depriving the fire of oxygen but not
electrocuting anyone by throwing water around. But there's the danger
of suffocation if the system goes off and there's someone trapped
nearby.


I had an MRI scan recently, and the room had a very, very heavy steel
door that appeared air tight. I assume that was to protect the rest of
the building if the helium boiled?



https://www.webmd.com/a-to-z-guides/...-of-its-kind#1

"Accompanying nurse from the wards attempted to bring an unchecked
oxygen cylinder into the magnet room despite being briefed beforehand in
relation to safety around the MRI and specifically the oxygen cylinder.
After being stopped by radiographers from taking cylinder any closer to
the machine and potentially causing serious harm to both patient and
equipment the nurse was unapologetic and did not seem to understand the
gravity of the situation despite all the prior warnings." :-

https://www.google.co.uk/url?sa=t&rc...hyTEdneFyr Yc

On 04/10/2020 16:21, Andrew wrote:
On 04/10/2020 13:44, GB wrote:
On 04/10/2020 12:58, Chris Hogg wrote:
On Sun, 4 Oct 2020 12:34:51 +0100, nightjar wrote:

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it
burning
inside whilst water is put on the outside. Usual cries for
sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what
about a
simple array of pipes in the roof space with open nozzles. In the
event of
a fire then the Fire Engine hooks up and dowses the fire from the
inside
using the fixed nozzles - no need to enter the building. Notre Dame
would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but
has the
advantage of not being automatic and able to flood the building.


Unlike a sprinkler system, which releases water only in the vicinity of
the fire, that would release water throughout the building. Fine if the
whole building is on fire, but it could result in unnecessary water
damage if the fire were only localised.

There are dry sprinkler systems. They contain compressed air or
nitrogen, but they still need a detector head to activate. That
releases
the gas which, in turn, activates a valve that allows water to enter
the
system.

IIRC large electrical installations such as large switch rooms in
basements etc have CO2 cylinders installed and ready to be discharged
in case of fire, thereby depriving the fire of oxygen but not
electrocuting anyone by throwing water around. But there's the danger
of suffocation if the system goes off and there's someone trapped
nearby.


I had an MRI scan recently, and the room had a very, very heavy steel
door that appeared air tight. I assume that was to protect the rest of
the building if the helium boiled?



https://www.webmd.com/a-to-z-guides/...-of-its-kind#1


"Accompanying nurse from the wards attempted to bring an unchecked
oxygen cylinder into the magnet room despite being briefed beforehand in
relation to safety around the MRI and specifically the oxygen cylinder.
After being stopped by radiographers from taking cylinder any closer to
the machine and potentially causing serious harm to both patient and
equipment the nurse was unapologetic and did not seem to understand the
gravity of the situation despite all the prior warnings." :-

https://www.google.co.uk/url?sa=t&rc...hyTEdneFyr Yc



Some M&S pants have a little tiny metal badge attached. Mine did, on the
day I had a pelvic MRI scan. The radiologist didn't notice it, and I
forgot about it. It's some sort of alloy and probably weighs a gram.

It didn't ping into the magnet, so probably non-ferrous. It didn't heat
up from the RF radiation. But, it did cast a shadow on the scans.
Fortunately, the radiologist had some scissors handy, and it only took
an extra 15 minutes to redo the scans.

On Sun, 04 Oct 2020 11:15:14 GMT, JohnP wrote:

A school has just gone up in flames in my area. Usual photos of it burning
inside whilst water is put on the outside. Usual cries for sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what about a
simple array of pipes in the roof space with open nozzles. In the event of
a fire then the Fire Engine hooks up and dowses the fire from the inside
using the fixed nozzles - no need to enter the building. Notre Dame would
have possibly been saved if such a simple system was in place.

And the 2000 pigs that recently burned to death , trapped in their
tiny pens. ;-(

Any thoughts? It seems a compromise to a full sprinkler system but has the
advantage of not being automatic and able to flood the building.

I can't understand why they didn't have such a thing in the pig farm,
after all, there is hardly anything that was likely to be more damaged
by water than fire (including the pigs).

Or a fail-safe exit system that gave the poor things a chance to
escape such a death (not that they had much of a life, burning to
death can't be a nice way to go).

Cheers, T i m

Being automatic is a considerable advantage, with sprinklers the fire
is usually out or well contained before the fire service arrives.
Flooding a building is generally a really bad idea, the water damage
is often more expensive than the fire damage.


The wax motor seems a better idea than the glass vials.

On 04/10/2020 16:52, GB wrote:
On 04/10/2020 16:21, Andrew wrote:
On 04/10/2020 13:44, GB wrote:
On 04/10/2020 12:58, Chris Hogg wrote:
On Sun, 4 Oct 2020 12:34:51 +0100, nightjar wrote:

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it
burning
inside whilst water is put on the outside. Usual cries for
sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but
what about a
simple array of pipes in the roof space with open nozzles. In the
event of
a fire then the Fire Engine hooks up and dowses the fire from the
inside
using the fixed nozzles - no need to enter the building. Notre
Dame would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but
has the
advantage of not being automatic and able to flood the building.


Unlike a sprinkler system, which releases water only in the
vicinity of
the fire, that would release water throughout the building. Fine if
the
whole building is on fire, but it could result in unnecessary water
damage if the fire were only localised.

There are dry sprinkler systems. They contain compressed air or
nitrogen, but they still need a detector head to activate. That
releases
the gas which, in turn, activates a valve that allows water to
enter the
system.

IIRC large electrical installations such as large switch rooms in
basements etc have CO2 cylinders installed and ready to be discharged
in case of fire, thereby depriving the fire of oxygen but not
electrocuting anyone by throwing water around. But there's the danger
of suffocation if the system goes off and there's someone trapped
nearby.


I had an MRI scan recently, and the room had a very, very heavy steel
door that appeared air tight. I assume that was to protect the rest
of the building if the helium boiled?



https://www.webmd.com/a-to-z-guides/...-of-its-kind#1


"Accompanying nurse from the wards attempted to bring an unchecked
oxygen cylinder into the magnet room despite being briefed beforehand
in relation to safety around the MRI and specifically the oxygen
cylinder. After being stopped by radiographers from taking cylinder
any closer to the machine and potentially causing serious harm to both
patient and equipment the nurse was unapologetic and did not seem to
understand the gravity of the situation despite all the prior
warnings." :-

https://www.google.co.uk/url?sa=t&rc...hyTEdneFyr Yc



Some M&S pants have a little tiny metal badge attached. Mine did, on the
day I had a pelvic MRI scan. The radiologist didn't notice it, and I
forgot about it. It's some sort of alloy and probably weighs a gram.

It didn't ping into the magnet, so probably non-ferrous. It didn't heat
up from the RF radiation. But, it did cast a shadow on the scans.
Fortunately, the radiologist had some scissors handy, and it only took
an extra 15 minutes to redo the scans.

Circumcision or castration ?. :-)

On 04/10/2020 17:38, Andrew wrote:
On 04/10/2020 16:52, GB wrote:
On 04/10/2020 16:21, Andrew wrote:
On 04/10/2020 13:44, GB wrote:
On 04/10/2020 12:58, Chris Hogg wrote:
On Sun, 4 Oct 2020 12:34:51 +0100, nightjar wrote:

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of
it burning
inside whilst water is put on the outside. Usual cries for
sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but
what about a
simple array of pipes in the roof space with open nozzles. In the
event of
a fire then the Fire Engine hooks up and dowses the fire from the
inside
using the fixed nozzles - no need to enter the building. Notre
Dame would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system
but has the
advantage of not being automatic and able to flood the building.


Unlike a sprinkler system, which releases water only in the
vicinity of
the fire, that would release water throughout the building. Fine
if the
whole building is on fire, but it could result in unnecessary water
damage if the fire were only localised.

There are dry sprinkler systems. They contain compressed air or
nitrogen, but they still need a detector head to activate. That
releases
the gas which, in turn, activates a valve that allows water to
enter the
system.

IIRC large electrical installations such as large switch rooms in
basements etc have CO2 cylinders installed and ready to be discharged
in case of fire, thereby depriving the fire of oxygen but not
electrocuting anyone by throwing water around. But there's the danger
of suffocation if the system goes off and there's someone trapped
nearby.


I had an MRI scan recently, and the room had a very, very heavy
steel door that appeared air tight. I assume that was to protect the
rest of the building if the helium boiled?



https://www.webmd.com/a-to-z-guides/...-of-its-kind#1


"Accompanying nurse from the wards attempted to bring an unchecked
oxygen cylinder into the magnet room despite being briefed beforehand
in relation to safety around the MRI and specifically the oxygen
cylinder. After being stopped by radiographers from taking cylinder
any closer to the machine and potentially causing serious harm to
both patient and equipment the nurse was unapologetic and did not
seem to understand the gravity of the situation despite all the prior
warnings." :-

https://www.google.co.uk/url?sa=t&rc...hyTEdneFyr Yc



Some M&S pants have a little tiny metal badge attached. Mine did, on
the day I had a pelvic MRI scan. The radiologist didn't notice it, and
I forgot about it. It's some sort of alloy and probably weighs a gram.

It didn't ping into the magnet, so probably non-ferrous. It didn't
heat up from the RF radiation. But, it did cast a shadow on the scans.
Fortunately, the radiologist had some scissors handy, and it only took
an extra 15 minutes to redo the scans.

Circumcision or castration ?. :-)

I was worried at the time, but it was just a badge-ectomy.

On 04/10/2020 16:07, Andrew wrote:


I was an IT contractor at an insurabnce co in Croydon where the
door to the computer room on the top floor had two push buttons,
one to ring the bell to request entrance, and the other to set off
the Halon fire extinguishers.
This was actually activated twice during a 4 year period by people
who thought it was the door entrance button, despite being protected
by a sliding perspex cover and clearly marked.


Expensive! For every foolproof system.....

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it burning
inside whilst water is put on the outside. Usual cries for sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what about a
simple array of pipes in the roof space with open nozzles. In the event of
a fire then the Fire Engine hooks up and dowses the fire from the inside
using the fixed nozzles - no need to enter the building. Notre Dame would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but has the
advantage of not being automatic and able to flood the building.

It's a bit like the Grenfell argument. You need to do a cost benefit
analysis including the cost of false actuation. Apart from paper and
desks, schools are mostly not particularly flammable. OK they contain
computers these days, but even computers are cheap.

Sprinklers make sense in department stores and many types of factory
because the contents are high value, and they prevent spread.

High pressure "misting" systems are used around rotating plant in power
stations where there are large lubricating oil tanks. Power stations
typically have dry risers too.

newshound wrote in
:

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it
burning inside whilst water is put on the outside. Usual cries for
sprinklers - but these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what
about a simple array of pipes in the roof space with open nozzles. In
the event of a fire then the Fire Engine hooks up and dowses the fire
from the inside using the fixed nozzles - no need to enter the
building. Notre Dame would have possibly been saved if such a simple
system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but
has the advantage of not being automatic and able to flood the
building.

It's a bit like the Grenfell argument. You need to do a cost benefit
analysis including the cost of false actuation. Apart from paper and
desks, schools are mostly not particularly flammable. OK they contain
computers these days, but even computers are cheap.

Sprinklers make sense in department stores and many types of factory
because the contents are high value, and they prevent spread.

High pressure "misting" systems are used around rotating plant in
power stations where there are large lubricating oil tanks. Power
stations typically have dry risers too.


Grenfell should have had a Dry Riser.

Thing is, I went to school in the 1960s and my secondary school had
sprinklers all over it. Seems a bit odd if some still do not have them to
me, maybe it was very old.
Brian

--
--
This newsgroup posting comes to you directly from...
The Sofa of Brian Gaff...

Blind user, so no pictures please
Note this Signature is meaningless.!
"JohnP" wrote in message
. ..
A school has just gone up in flames in my area. Usual photos of it burning
inside whilst water is put on the outside. Usual cries for sprinklers -
but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what about
a
simple array of pipes in the roof space with open nozzles. In the event of
a fire then the Fire Engine hooks up and dowses the fire from the inside
using the fixed nozzles - no need to enter the building. Notre Dame would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but has the
advantage of not being automatic and able to flood the building.

On 04/10/2020 12:58, Chris Hogg wrote:
On Sun, 4 Oct 2020 12:34:51 +0100, nightjar wrote:

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of it burning
inside whilst water is put on the outside. Usual cries for sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but what about a
simple array of pipes in the roof space with open nozzles. In the event of
a fire then the Fire Engine hooks up and dowses the fire from the inside
using the fixed nozzles - no need to enter the building. Notre Dame would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system but has the
advantage of not being automatic and able to flood the building.


Unlike a sprinkler system, which releases water only in the vicinity of
the fire, that would release water throughout the building. Fine if the
whole building is on fire, but it could result in unnecessary water
damage if the fire were only localised.

There are dry sprinkler systems. They contain compressed air or
nitrogen, but they still need a detector head to activate. That releases
the gas which, in turn, activates a valve that allows water to enter the
system.

IIRC large electrical installations such as large switch rooms in
basements etc have CO2 cylinders installed and ready to be discharged
in case of fire, thereby depriving the fire of oxygen but not
electrocuting anyone by throwing water around. But there's the danger
of suffocation if the system goes off and there's someone trapped
nearby.


Although, in the case of a dry sprinkler system, the gas is not pat of
the fire suppression system. It simply keeps the pipework under pressure
until a sprinkler head is activated. The drop in pressure releases a
valve that allows water into the pipework. They are mainly used in
unheated areas where there is a risk that, if the pipes were kept full
of water, it could freeze.

--
Colin Bignell

On 04/10/2020 22:21, JohnP wrote:
newshound wrote in


Grenfell should have had a Dry Riser.

No, Grenfell should *not* have had that disastrous cladding.

On 05/10/2020 11:38, newshound wrote:
On 04/10/2020 22:21, JohnP wrote:
newshound wrote in


Grenfell should have had a Dry Riser.

No, Grenfell should *not* have had that disastrous cladding.

A fire resistant window to the flat where the fire started would have
avoided it getting to the cladding.

--
Colin Bignell

On 05/10/2020 12:05, nightjar wrote:
On 05/10/2020 11:38, newshound wrote:
On 04/10/2020 22:21, JohnP wrote:
newshound wrote in


Grenfell should have had a Dry Riser.

No, Grenfell should *not* have had that disastrous cladding.

A fire resistant window to the flat where the fire started would have
avoided it getting to the cladding.

True, though I am not sure how easy that is to engineer. OK, wired glass
would work, but that's not so nice for residential accomodation. I guess
"bulletproof" glass would provide 30 minute or better resistance, but
would standard sealed double glazing work even in metal frames? (I'm not
sure exactly what did fail).

On 05/10/2020 13:20, newshound wrote:
On 05/10/2020 12:05, nightjar wrote:
On 05/10/2020 11:38, newshound wrote:
On 04/10/2020 22:21, JohnP wrote:
newshound wrote in


Grenfell should have had a Dry Riser.

No, Grenfell should *not* have had that disastrous cladding.

A fire resistant window to the flat where the fire started would have
avoided it getting to the cladding.

True, though I am not sure how easy that is to engineer. OK, wired glass
would work, but that's not so nice for residential accomodation. I guess
"bulletproof" glass would provide 30 minute or better resistance, but
would standard sealed double glazing work even in metal frames? (I'm not
sure exactly what did fail).

AIUI the plastic frames melted, allowing the glass to drop out.

Fire rated windows are commercially available in 30 mins 60 mins, 120
mins and even 180 mins ratings. This is one company offering fire rated
windows:

https://www.fireratedwindows.co.uk/

There are various ways to get fire resistant glass. This is one:

https://www.vetrotech.com/en-gb/contraflam

--
Colin Bignell

On 05/10/2020 12:05, nightjar wrote:
On 05/10/2020 11:38, newshound wrote:
On 04/10/2020 22:21, JohnP wrote:
newshound wrote in


Grenfell should have had a Dry Riser.

No, Grenfell should *not* have had that disastrous cladding.

A fire resistant window to the flat where the fire started would have
avoided it getting to the cladding.


All the windows were replaced as part of the refurb. It was the
incorrect expanding PU foam sealant around the frame perimeter
that allowed the kitchen fire to get out into the external
cladding, where it spread rapidly.

"Brian Gaff \(Sofa\)" wrote in
:

Thing is, I went to school in the 1960s and my secondary school had
sprinklers all over it. Seems a bit odd if some still do not have them
to me, maybe it was very old.
Brian


My other idea - after seeing firefighter playing their hoses on the outside
of buildings - A metal pipe - several metres in length - a sort of
"battering ram" with a hose connection on the back end and jet holes around
the circumference toward the opposite end. Poke it into the building and
turn on the water to provide a deluge on the inside.

On 05/10/2020 17:06, Andrew wrote:
On 05/10/2020 12:05, nightjar wrote:
On 05/10/2020 11:38, newshound wrote:
On 04/10/2020 22:21, JohnP wrote:
newshound wrote in


Grenfell should have had a Dry Riser.

No, Grenfell should *not* have had that disastrous cladding.

A fire resistant window to the flat where the fire started would have
avoided it getting to the cladding.


All the windows were replaced as part of the refurb. It was the
incorrect expanding PU foam sealant around the frame perimeter
that allowed the kitchen fire to get out into the external
cladding, where it spread rapidly.

The poor quality of the installation suggests that they went for the
lowest quote, which would not have been to fit fire resistant windows.

--
Colin Bignell

On 05/10/2020 16:48, nightjar wrote:
On 05/10/2020 13:20, newshound wrote:
On 05/10/2020 12:05, nightjar wrote:
On 05/10/2020 11:38, newshound wrote:
On 04/10/2020 22:21, JohnP wrote:
newshound wrote in


Grenfell should have had a Dry Riser.

No, Grenfell should *not* have had that disastrous cladding.

A fire resistant window to the flat where the fire started would have
avoided it getting to the cladding.

True, though I am not sure how easy that is to engineer. OK, wired
glass would work, but that's not so nice for residential accomodation.
I guess "bulletproof" glass would provide 30 minute or better
resistance, but would standard sealed double glazing work even in
metal frames? (I'm not sure exactly what did fail).

AIUI the plastic frames melted, allowing the glass to drop out.

Fire rated windows are commercially available in 30 mins 60 mins, 120
mins and even 180 mins ratings. This is one company offering fire rated
windows:

https://www.fireratedwindows.co.uk/

There are various ways to get fire resistant glass. This is one:

https://www.vetrotech.com/en-gb/contraflam

Very interesting, thanks. Not cheap, though, I guess. And I'm sure it
will come out in the enquiry how the whole refurb was based on minimum
quotes.

Does this perhaps mean that for blocks still insulated with "dangerous"
panels one option would be just to replace the windows with fire
resistant ones?

GB Wrote in message:
On 04/10/2020 17:38, Andrew wrote:
On 04/10/2020 16:52, GB wrote:
On 04/10/2020 16:21, Andrew wrote:
On 04/10/2020 13:44, GB wrote:
On 04/10/2020 12:58, Chris Hogg wrote:
On Sun, 4 Oct 2020 12:34:51 +0100, nightjar wrote:

On 04/10/2020 12:15, JohnP wrote:
A school has just gone up in flames in my area. Usual photos of
it burning
inside whilst water is put on the outside. Usual cries for
sprinklers - but
these can be vandalised and could cause problems.

I know about dry risers - usually to Landing Hose Unions - but
what about a
simple array of pipes in the roof space with open nozzles. In the
event of
a fire then the Fire Engine hooks up and dowses the fire from the
inside
using the fixed nozzles - no need to enter the building. Notre
Dame would
have possibly been saved if such a simple system was in place.

Any thoughts? It seems a compromise to a full sprinkler system
but has the
advantage of not being automatic and able to flood the building.


Unlike a sprinkler system, which releases water only in the
vicinity of
the fire, that would release water throughout the building. Fine
if the
whole building is on fire, but it could result in unnecessary water
damage if the fire were only localised.

There are dry sprinkler systems. They contain compressed air or
nitrogen, but they still need a detector head to activate. That
releases
the gas which, in turn, activates a valve that allows water to
enter the
system.

IIRC large electrical installations such as large switch rooms in
basements etc have CO2 cylinders installed and ready to be discharged
in case of fire, thereby depriving the fire of oxygen but not
electrocuting anyone by throwing water around. But there's the danger
of suffocation if the system goes off and there's someone trapped
nearby.


I had an MRI scan recently, and the room had a very, very heavy
steel door that appeared air tight. I assume that was to protect the
rest of the building if the helium boiled?



https://www.webmd.com/a-to-z-guides/...-of-its-kind#1


"Accompanying nurse from the wards attempted to bring an unchecked
oxygen cylinder into the magnet room despite being briefed beforehand
in relation to safety around the MRI and specifically the oxygen
cylinder. After being stopped by radiographers from taking cylinder
any closer to the machine and potentially causing serious harm to
both patient and equipment the nurse was unapologetic and did not
seem to understand the gravity of the situation despite all the prior
warnings." :-

https://www.google.co.uk/url?sa=t&rc...hyTEdneFyr Yc



Some M&S pants have a little tiny metal badge attached. Mine did, on
the day I had a pelvic MRI scan. The radiologist didn't notice it, and
I forgot about it. It's some sort of alloy and probably weighs a gram.

It didn't ping into the magnet, so probably non-ferrous. It didn't
heat up from the RF radiation. But, it did cast a shadow on the scans.
Fortunately, the radiologist had some scissors handy, and it only took
an extra 15 minutes to redo the scans.

Circumcision or castration ?. :-)

I was worried at the time, but it was just a badge-ectomy.



You kept quiet about the Prince Albert then?
--
Jimk


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

"Brian Gaff \(Sofa\)" wrote in
:

Thing is, I went to school in the 1960s and my secondary school had
sprinklers all over it. Seems a bit odd if some still do not have them
to me, maybe it was very old.
Brian


Many modern schools are such flimsy buildings that they probably wouldn't
support the pipes!

On 05/10/2020 20:40, newshound wrote:
On 05/10/2020 16:48, nightjar wrote:
On 05/10/2020 13:20, newshound wrote:
On 05/10/2020 12:05, nightjar wrote:
On 05/10/2020 11:38, newshound wrote:
On 04/10/2020 22:21, JohnP wrote:
newshound wrote in


Grenfell should have had a Dry Riser.

No, Grenfell should *not* have had that disastrous cladding.

A fire resistant window to the flat where the fire started would
have avoided it getting to the cladding.

True, though I am not sure how easy that is to engineer. OK, wired
glass would work, but that's not so nice for residential
accomodation. I guess "bulletproof" glass would provide 30 minute or
better resistance, but would standard sealed double glazing work even
in metal frames? (I'm not sure exactly what did fail).

AIUI the plastic frames melted, allowing the glass to drop out.

Fire rated windows are commercially available in 30 mins 60 mins, 120
mins and even 180 mins ratings. This is one company offering fire
rated windows:

https://www.fireratedwindows.co.uk/

There are various ways to get fire resistant glass. This is one:

https://www.vetrotech.com/en-gb/contraflam

Very interesting, thanks. Not cheap, though, I guess. And I'm sure it
will come out in the enquiry how the whole refurb was based on minimum
quotes.

Does this perhaps mean that for blocks still insulated with "dangerous"
panels one option would be just to replace the windows with fire
resistant ones?

From a technical point of view, it probably would. However, it is
unlikely it would allay the residents' fears.

--
Colin Bignell

JohnP wrote:
"Brian Gaff \(Sofa\)" wrote in
:

Thing is, I went to school in the 1960s and my secondary school had
sprinklers all over it. Seems a bit odd if some still do not have them
to me, maybe it was very old.
Brian


Many modern schools are such flimsy buildings that they probably wouldn't
support the pipes!

We had a brick-clad school here burn to the ground years ago.
Around 1974 or so.

It turns out the wall insulation was flammable. Oops.

No amount of water could put out that fire. It raced
through the walls and false ceiling at breakneck speed.
The firemen mounted a roof attack, but they had to retreat
because their estimate of what would be a safe place to
saw open the roof, was way off. They got off the roof
before it collapsed, so they were well clear of that
fortunately. No close call. But once they did the maths,
there was no place to mount a second attack.

The school might well have had sprinklers, but all they
would do is wet the sheetrock walls, and not touch the
fire inside the walls at all.

The next day, all they had left to do, was knock down the
few remaining sections of intact brick wall.

Just as important as sprinklers, is enforcing some kind
of building code. I guess nobody had a look inside
the walls, to see what was in there.

They built a school to replace it (they don't always do that).
The new school had brick cladding, because, you know, it
doesn't burn :-/

Paul

GB wrote:
I had an MRI scan recently, and the room had a very, very heavy steel
door that appeared air tight. I assume that was to protect the rest of
the building if the helium boiled?

No. It was to protect the rest of the building if
you accidentally developed superpowers whilst your
atomic nuclei were being magnetically resonanated.

#Paul

On 06/10/2020 09:30, nightjar wrote:
On 05/10/2020 20:40, newshound wrote:


Does this perhaps mean that for blocks still insulated with
"dangerous" panels one option would be just to replace the windows
with fire resistant ones?

From a technical point of view, it probably would. However, it is
unlikely it would allay the residents' fears.

True. But I would be happy to live in one if a good proportion of
windows had been replaced, or if it was a block with decent stairwell
forced ventilation. I'd have smoke detectors, and would get out at any
sign of fire or alarm.

On 06/10/2020 08:54, JohnP wrote:
"Brian Gaff \(Sofa\)" wrote in
:

Thing is, I went to school in the 1960s and my secondary school had
sprinklers all over it. Seems a bit odd if some still do not have them
to me, maybe it was very old.
Brian


Many modern schools are such flimsy buildings that they probably wouldn't
support the pipes!


Which was the argument against water bombing the burning Notre Dame
from a helicopter

On 06/10/2020 11:17, Paul wrote:
JohnP wrote:
"Brian Gaff \(Sofa\)" wrote in
:
Thing is, I went to school in the 1960s and my secondary school had
sprinklers all over it. Seems a bit odd if some still do not have them
to me, maybe it was very old.
Â*Brian


Many modern schools are such flimsy buildings that they probably
wouldn't support the pipes!

We had a brick-clad school here burn to the ground years ago.
Around 1974 or so.

It turns out the wall insulation was flammable. Oops.

No amount of water could put out that fire. It raced
through the walls and false ceiling at breakneck speed.
The firemen mounted a roof attack, but they had to retreat
because their estimate of what would be a safe place to
saw open the roof, was way off. They got off the roof
before it collapsed, so they were well clear of that
fortunately. No close call. But once they did the maths,
there was no place to mount a second attack.

The school might well have had sprinklers, but all they
would do is wet the sheetrock walls, and not touch the
fire inside the walls at all.

The next day, all they had left to do, was knock down the
few remaining sections of intact brick wall.

Just as important as sprinklers, is enforcing some kind
of building code. I guess nobody had a look inside
the walls, to see what was in there.

They built a school to replace it (they don't always do that).
The new school had brick cladding, because, you know, it
doesn't burn :-/

Â*Â* Paul

There have been more than one total-loss fires in the UK
involving quite new blocks of flats. Either they had
incorrect fire-stopping where pipes pass through floors
or missing/inadequate cavity fire barriers, or both.

Plasterboard/sheetrock should have 60 minute fire resistance
(depending on construction), so it comes back to ****-poor
supervision of people making holes for pipes and cables,
notably works done long after construction. The best
building codes in the world won't stop an electricion or
network installer destroying the fire integrity long after
it was built.