On Thu, 31 May 2012 00:59:40 -0700 (PDT), Jonathan wrote:

Our smoke detectors are very sensitive. Would sprinklers be triggered
by the same mechanism, resulting in a wet house whenever the toast is
burnt!

Unlikely. They are a small glass bubble holding the water back, this
bubble is full of a liquid that expands when it gets hot shattering
the bubble and thus letting the water out. From the films I've seen
of commercial sprinkler systems the fire has to be quite large (in
domestic terms) before they go off and when they do it will be new
furnishing and decorating for at least that room. Possibly
replastering and new floor as well if it's chipboard...

http://www.staysafeuk.com/domestic-sprinklers.html

"... activate within four minutes ..."
"... about 150 liters/min ..."

A domestic fire will have quite a hold within four minutes, there
will be a lot of smoke about. A typical smoke alarm will have gone
off a lot earlier to alert any occupants to "Get Out, Stay Out, Get
the Brigade out". Buildings and contents can be replaced you don't
need to "save" them. Educating people to have a "fire plan" and to
get the F out when the alarm sounds be that in the home or work
place.

150l is a large bath full of water, every minute... I wonder where
this water comes from? Most domestic supplies can't deliver that sort
of flow, so how effective at extinguishing a fire large enough to
trigger the sprinkler is a domestic sprinkler?

One also assumes that these sprinkler systems will have an external
water flow driven bell and a link to a service centre that can call
the Fire Brigade out. If you did have a fire that triggered the
sprinklers just after you gone on your two weeks to Malaga, without
such systems there wouldn't be much, possibly no, indication that the
inside is being drenched....

Then of course how vulnerable will they be to being knocked?
Sprinklers are normally installed high up not the relatively low 8'
ceiling of a house.

Strikes me of politicians/bureaucrats reacting to "some one died"
with "we must do something". Personally linked smoke/heat alarms are
enough, along with decent public education. That would have far
greater benefit to society but far harder to measure so the
bureaucrats won't like it as they can't justify their existence.

Do any of the Fire Services still have the chip pan fire demo
vehicles that they used to take around Fetes, Gala Days and County
Shows? It's no use telling people how to safely deal with a chip pan
fire it'll just go in one ear and out the other. Show 'em, in quite
dramatic terms, what happens when you do it wrong. OK I guess the
open chip pan is getting to be a thing of the past these days but it
will still highlight the dangers of fire. Most people these days do
not have any real experience of fire, most homes no longer have open
fires, people don't have bonfires to dispose of waste (garden or
otherwise), kids don't make camp fires.

--
Cheers
Dave.

Dave Liquorice wrote
Jonathan wrote

Our smoke detectors are very sensitive. Would sprinklers
be triggered by the same mechanism, resulting in a wet
house whenever the toast is burnt!

Unlikely. They are a small glass bubble holding the water back, this
bubble is full of a liquid that expands when it gets hot shattering
the bubble and thus letting the water out. From the films I've seen
of commercial sprinkler systems the fire has to be quite large (in
domestic terms) before they go off and when they do it will be new
furnishing and decorating for at least that room. Possibly
replastering and new floor as well if it's chipboard...

http://www.staysafeuk.com/domestic-sprinklers.html

"... activate within four minutes ..."
"... about 150 liters/min ..."

A domestic fire will have quite a hold within four minutes,

Not necessarily, depends on where the fire happens.

there will be a lot of smoke about.

Not necessarily, depends on where the fire happens.

A typical smoke alarm will have gone off a lot earlier to alert
any occupants to "Get Out, Stay Out, Get the Brigade out".

And it is cost effective to mandate those.

Buildings and contents can be replaced you don't need to
"save" them. Educating people to have a "fire plan" and to
get the F out when the alarm sounds be that in the home
or work place.

150l is a large bath full of water, every minute...
I wonder where this water comes from?

The mains.

Most domestic supplies can't deliver that sort of flow,
so how effective at extinguishing a fire large enough
to trigger the sprinkler is a domestic sprinkler?

Presumably someone has measured that.

Corse it gets tricky with domestic fat fires which are in
fact one of the most common fires in domestic situations.

One also assumes that these sprinkler systems will
have an external water flow driven bell and a link
to a service centre that can call the Fire Brigade out.

Most don't with domestic sprinkler systems.

If you did have a fire that triggered the sprinklers just
after you gone on your two weeks to Malaga, without
such systems there wouldn't be much, possibly no,
indication that theinside is being drenched....

Sure, but that's no worse than a burst pipe.

Then of course how vulnerable will they be to being knocked?

Not very at all.

Sprinklers are normally installed high up
not the relatively low 8' ceiling of a house.

Sure, but the worst that happens is things get very wet.

Strikes me of politicians/bureaucrats reacting to
"some one died" with "we must do something".

They arent even mandated in rental property.

Personally linked smoke/heat alarms are
enough, along with decent public education.

Not even linked.

That would have far greater benefit to society but far harder to measure
so the bureaucrats won't like it as they can't justify their existence.

Do any of the Fire Services still have the chip pan fire demo vehicles
that they used to take around Fetes, Gala Days and County Shows?

Yes, ours still do. And have fire brigade open days where they do that too.

And do it at the bigger workplaces too.

It's no use telling people how to safely deal with a chip pan
fire it'll just go in one ear and out the other. Show 'em, in quite
dramatic terms, what happens when you do it wrong. OK I guess
the open chip pan is getting to be a thing of the past these days

It isnt with domestic fires, its still the major source of domestic fires.

but it will still highlight the dangers of fire. Most people
these days do not have any real experience of fire,

Most didn't even in the past.

most homes no longer have open fires,

Very few of those ever burnt the house down.

people don't have bonfires to dispose
of waste (garden or otherwise),

We do.

kids don't make camp fires.

Ours do.

When I was building the house, I was silly enough to let
the kids burn the small tree that I had to dig up because
it was where the house was going to go. I didn't realise
how keen kids were about fires. Had a hell of a problem
finding much scrap wood around after that.

On 31/05/2012 10:11, Dave Liquorice wrote:
On Thu, 31 May 2012 00:59:40 -0700 (PDT), Jonathan wrote:

Our smoke detectors are very sensitive. Would sprinklers be triggered
by the same mechanism, resulting in a wet house whenever the toast is
burnt!

Unlikely. They are a small glass bubble holding the water back, this
bubble is full of a liquid that expands when it gets hot shattering
the bubble and thus letting the water out. From the films I've seen
of commercial sprinkler systems the fire has to be quite large (in
domestic terms) before they go off and when they do it will be new
furnishing and decorating for at least that room. Possibly
replastering and new floor as well if it's chipboard...

http://www.staysafeuk.com/domestic-sprinklers.html

"... activate within four minutes ..."
"... about 150 liters/min ..."

A domestic fire will have quite a hold within four minutes, there
will be a lot of smoke about. A typical smoke alarm will have gone
off a lot earlier to alert any occupants to "Get Out, Stay Out, Get
the Brigade out". Buildings and contents can be replaced you don't
need to "save" them. Educating people to have a "fire plan" and to
get the F out when the alarm sounds be that in the home or work
place.

150l is a large bath full of water, every minute... I wonder where
this water comes from? Most domestic supplies can't deliver that sort
of flow, so how effective at extinguishing a fire large enough to
trigger the sprinkler is a domestic sprinkler?

The Fire Protection Association suggest a design flow rate of 60l/min
for a domestic installation. It would be normal to supply a sprinkler
system from stored water, in case the mains supply is, for some reason,
not available when the sprinkler system is needed.

One also assumes that these sprinkler systems will have an external
water flow driven bell and a link to a service centre that can call
the Fire Brigade out. If you did have a fire that triggered the
sprinklers just after you gone on your two weeks to Malaga, without
such systems there wouldn't be much, possibly no, indication that the
inside is being drenched....

Sprinkler systems usually activate a local alarm and can send a signal
to a remote location, if that is specified in the design. However, you
can also have a limit set on the total volume of water released, either
with flow measuring devices linked to valves or simply by having a
storage tank that does not automatically refill.

Then of course how vulnerable will they be to being knocked?
Sprinklers are normally installed high up not the relatively low 8'
ceiling of a house....

The frames around the glass bulb are generally very strong and you can
also get flush fitting spray heads.

Colin Bignell

Nightjar wrote
Dave Liquorice wrote
Jonathan wrote

Our smoke detectors are very sensitive. Would sprinklers
be triggered by the same mechanism, resulting in a wet
house whenever the toast is burnt!

Unlikely. They are a small glass bubble holding the water back, this
bubble is full of a liquid that expands when it gets hot shattering
the bubble and thus letting the water out. From the films I've seen
of commercial sprinkler systems the fire has to be quite large (in
domestic terms) before they go off and when they do it will be new
furnishing and decorating for at least that room. Possibly
replastering and new floor as well if it's chipboard...

http://www.staysafeuk.com/domestic-sprinklers.html

"... activate within four minutes ..."
"... about 150 liters/min ..."

A domestic fire will have quite a hold within four minutes, there
will be a lot of smoke about. A typical smoke alarm will have gone
off a lot earlier to alert any occupants to "Get Out, Stay Out, Get
the Brigade out". Buildings and contents can be replaced you don't
need to "save" them. Educating people to have a "fire plan" and to
get the F out when the alarm sounds be that in the home or work place.

150l is a large bath full of water, every minute... I wonder where
this water comes from? Most domestic supplies can't deliver that sort
of flow, so how effective at extinguishing a fire large enough to
trigger the sprinkler is a domestic sprinkler?

The Fire Protection Association suggest a design flow rate of 60l/min
for a domestic installation. It would be normal to supply a sprinkler
system from stored water, in case the mains supply is, for some reason,
not available when the sprinkler system is needed.

Very few of ours are, they are just supplied with mains pressure water.

One also assumes that these sprinkler systems will have an external
water flow driven bell and a link to a service centre that can call
the Fire Brigade out. If you did have a fire that triggered the
sprinklers just after you gone on your two weeks to Malaga, without
such systems there wouldn't be much, possibly no, indication that the
inside is being drenched....

Sprinkler systems usually activate a local alarm and can send a signal
to a remote location, if that is specified in the design. However, you
can also have a limit set on the total volume of water released, either
with flow measuring devices linked to valves or simply by having a
storage tank that does not automatically refill.

Then of course how vulnerable will they be to being knocked?
Sprinklers are normally installed high up not the relatively low 8'
ceiling of a house....

The frames around the glass bulb are generally very strong and you can
also get flush fitting spray heads.

On Thu, 31 May 2012 10:11:30 +0100 (BST), "Dave Liquorice"
wrote:

Then of course how vulnerable will they be to being knocked?
Sprinklers are normally installed high up not the relatively low 8'
ceiling of a house.

Domestic ones are retracted into the ceiling and a flush cap over
them. They drop down and sprinkle.