OK so not DIY but some here do find such info interesting.

I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

Out of the 16 I have tested 8 of them have either had the MCB to the
smokes turned off and the battery removed, the mains disconnected at the
smoke and the battery removed or the smoke heads have been removed.


I accept that the tenants have probably done some of this DIY themselves
to save buying a new battery.

However the most disturbing one is a flat that a tenant moved into 4
weeks ago. The mains had been disconnected from the smoke, taped up and
shoved into the ceiling as well as the battery having been removed.
Almost certainly like that when she moved in 4 weeks ago.

--
Adam

On 22/11/2018 19:14, ARW wrote:
OK so not DIY but some here do find such info interesting.

I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

Out of the 16 I have tested 8 of them have either had the MCB to the
smokes turned off and the battery removed, the mains disconnected at the
smoke and the battery removed or the smoke heads have been removed.


I accept that the tenants have probably done some of this DIY themselves
to save buying a new battery.

However the most disturbing one is a flat that a tenant moved into 4
weeks ago. The mains had been disconnected from the smoke, taped up and
shoved into the ceiling as well as the battery having been removed.
Almost certainly like that when she moved in 4 weeks ago.

If they are linked burning toast in one flat will set them all off.

--
Max Demian

On Thursday, 22 November 2018 19:14:09 UTC, ARW wrote:
I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

I don't know how much smoke detectors have changed, but my five never have false alarms. I have to go around testing them intentionally.

Or perhaps my cooking's got better.

Owain

On 22/11/2018 19:14, ARW wrote:
OK so not DIY but some here do find such info interesting.

I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

Out of the 16 I have tested 8 of them have either had the MCB to the
smokes turned off and the battery removed, the mains disconnected at the
smoke and the battery removed or the smoke heads have been removed.


I accept that the tenants have probably done some of this DIY themselves
to save buying a new battery.

However the most disturbing one is a flat that a tenant moved into 4
weeks ago. The mains had been disconnected from the smoke, taped up and
shoved into the ceiling as well as the battery having been removed.
Almost certainly like that when she moved in 4 weeks ago.


It's a sad reflection on both landlord and tenants. I can only hope the
EICR is for a new owner/agent who wants to do better and not just 'cos
the insurer wants one.

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

On 22/11/18 21:37, wrote:
On Thursday, 22 November 2018 19:14:09 UTC, ARW wrote:
I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

I don't know how much smoke detectors have changed, but my five never have false alarms. I have to go around testing them intentionally.

Or perhaps my cooking's got better.

Owain


The only thing that sets mine off is plumbing soldering. Or very
occasionally if I griddle-pan chargrill several chicken breasts and
forget to open a door for the duration.

--
Email does not work

On 22/11/2018 21:45, Tim Watts wrote:
On 22/11/18 21:37, wrote:
On Thursday, 22 November 2018 19:14:09 UTC, ARWÂ* wrote:
I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

I don't know how much smoke detectors have changed, but my five never
have false alarms. I have to go around testing them intentionally.

Or perhaps my cooking's got better.

Owain


The only thing that sets mine off is plumbing soldering. Or very

Yup same here...

and all 4 are interlinked. Fortunately I fitted a mute/test/identify
switch next to the CU, so I now have people programmed to mute them when
I am plumbing! (it keeps them muted for about 10 mins as well)

--
Cheers,

John.

/================================================== ===============\
| Internode Ltd - http://www.internode.co.uk |
|-----------------------------------------------------------------|
| John Rumm - john(at)internode(dot)co(dot)uk |
\================================================= ================/

On Thursday, 22 November 2018 21:40:58 UTC, Robin wrote:
On 22/11/2018 19:14, ARW wrote:
OK so not DIY but some here do find such info interesting.

I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

Out of the 16 I have tested 8 of them have either had the MCB to the
smokes turned off and the battery removed, the mains disconnected at the
smoke and the battery removed or the smoke heads have been removed.


I accept that the tenants have probably done some of this DIY themselves
to save buying a new battery.

However the most disturbing one is a flat that a tenant moved into 4
weeks ago. The mains had been disconnected from the smoke, taped up and
shoved into the ceiling as well as the battery having been removed.
Almost certainly like that when she moved in 4 weeks ago.


It's a sad reflection on both landlord and tenants. I can only hope the
EICR is for a new owner/agent who wants to do better and not just 'cos
the insurer wants one.


I suspect it's one of those systems that false alarms too frequently for the tenants to tolerate it. There are such systems out there. Last one I saw they had difficulty accessing the 'turn it off' function too. People get seriously fed up & detectors get disabled.

The companies that put systems in don't always do it adequately in this respect, leaving an LL that doesn't know how to solve it. Some systems are genuinely not livable with.

I'd ask the tenants about it and maybe flag this as a likely explanation, recommending it be made livable.


NT

On Friday, 23 November 2018 01:27:56 UTC, wrote:
On Thursday, 22 November 2018 21:40:58 UTC, Robin wrote:
On 22/11/2018 19:14, ARW wrote:
OK so not DIY but some here do find such info interesting.

I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

Out of the 16 I have tested 8 of them have either had the MCB to the
smokes turned off and the battery removed, the mains disconnected at the
smoke and the battery removed or the smoke heads have been removed.


I accept that the tenants have probably done some of this DIY themselves
to save buying a new battery.

However the most disturbing one is a flat that a tenant moved into 4
weeks ago. The mains had been disconnected from the smoke, taped up and
shoved into the ceiling as well as the battery having been removed.
Almost certainly like that when she moved in 4 weeks ago.


It's a sad reflection on both landlord and tenants. I can only hope the
EICR is for a new owner/agent who wants to do better and not just 'cos
the insurer wants one.


I suspect it's one of those systems that false alarms too frequently for the tenants to tolerate it. There are such systems out there. Last one I saw they had difficulty accessing the 'turn it off' function too. People get seriously fed up & detectors get disabled.

The companies that put systems in don't always do it adequately in this respect, leaving an LL that doesn't know how to solve it. Some systems are genuinely not livable with.

I'd ask the tenants about it and maybe flag this as a likely explanation, recommending it be made livable.


NT

Frequent false alarms lead to people ignoring them too.
Years ago ISTR an incident where people in a tower block ignored the fire alarm for this reason, it was a real fire and someone was killed.

On Thu, 22 Nov 2018 20:50:03 +0000, Max Demian wrote:

However the most disturbing one is a flat that a tenant moved into
4
weeks ago. The mains had been disconnected from the smoke, taped
up and
shoved into the ceiling as well as the battery having been
removed.
Almost certainly like that when she moved in 4 weeks ago.

Implying that the Land Lord didn't check the detector as part of any
"pre delivery inspection".

If they are linked burning toast in one flat will set them all off.

Which depending on the buildings construction (and modifications)
might be a good thing... However such a system has to be fairly
immune to false alarms from burning toast, or the smokes will get
disabled. If the kitchen opens into the hallway the chances are it
won't be immune to false alarms. A hallway detector needs to be a
smoke based one not temperature.

--
Cheers
Dave.

Weird indeed. Seems people will do anything to save a few pounds rather than
worry about safety.
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.!
"ARW" wrote in message
...
OK so not DIY but some here do find such info interesting.

I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

Out of the 16 I have tested 8 of them have either had the MCB to the
smokes turned off and the battery removed, the mains disconnected at the
smoke and the battery removed or the smoke heads have been removed.


I accept that the tenants have probably done some of this DIY themselves
to save buying a new battery.

However the most disturbing one is a flat that a tenant moved into 4 weeks
ago. The mains had been disconnected from the smoke, taped up and shoved
into the ceiling as well as the battery having been removed. Almost
certainly like that when she moved in 4 weeks ago.

--
Adam

I don't think he said they are. Often it depends on the construction of the
building. Some blocks are designed so any fire in one flat is isolated by
the doors and windows of that build. IE what should have happened at
Grenville but was cocked up by the refurbishers.
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.!
"Max Demian" wrote in message
...
On 22/11/2018 19:14, ARW wrote:
OK so not DIY but some here do find such info interesting.

I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

Out of the 16 I have tested 8 of them have either had the MCB to the
smokes turned off and the battery removed, the mains disconnected at the
smoke and the battery removed or the smoke heads have been removed.


I accept that the tenants have probably done some of this DIY themselves
to save buying a new battery.

However the most disturbing one is a flat that a tenant moved into 4
weeks ago. The mains had been disconnected from the smoke, taped up and
shoved into the ceiling as well as the battery having been removed.
Almost certainly like that when she moved in 4 weeks ago.

If they are linked burning toast in one flat will set them all off.

--
Max Demian

On Thu, 22 Nov 2018 21:45:22 +0000, Tim Watts wrote:

I don't know how much smoke detectors have changed, but my five
never
have false alarms. I have to go around testing them intentionally.

Likewise, though I just put my ear defenders on (they are painfully
lound) and press the test switch on the Locate/Test/Silence switch
box and walk around rather than poking each one with a stick.

Or perhaps my cooking's got better.

The only thing that sets mine off is plumbing soldering. Or very
occasionally if I griddle-pan chargrill several chicken breasts and
forget to open a door for the duration.

Hum, kitchen ones ought to the "rate of rise" rather than "smoke"
detectors.
--
Cheers
Dave.

On 22/11/2018 20:50, Max Demian wrote:
On 22/11/2018 19:14, ARW wrote:
OK so not DIY but some here do find such info interesting.

I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke
in the hallway (as per regs when they were built in 1994)

Out of the 16 I have tested 8 of them have either had the MCB to the
smokes turned off and the battery removed, the mains disconnected at
the smoke and the battery removed or the smoke heads have been removed.


I accept that the tenants have probably done some of this DIY
themselves to save buying a new battery.

However the most disturbing one is a flat that a tenant moved into 4
weeks ago. The mains had been disconnected from the smoke, taped up
and shoved into the ceiling as well as the battery having been
removed. Almost certainly like that when she moved in 4 weeks ago.

If they are linked burning toast in one flat will set them all off.



No. Not interlinked. These are mains powered smokes in the flats
internal hallway. One smoke per flat.

The communal hallways are a different matter. ie they DO have
interlinked mains powered smoke alarms. A pity that they all have low
voltage batteries and the smokes are above the new suspended ceiling
that was installed 12 months ago. All you can hear when you walk down
the corridor is the smokes bleeping.

I will soon be installing a new 60 detector 8 zone bi wire fire alarm
system for the communal hallways.



--
Adam

On 23/11/2018 14:27, Dave Liquorice wrote:
On Thu, 22 Nov 2018 21:45:22 +0000, Tim Watts wrote:

I don't know how much smoke detectors have changed, but my five
never
have false alarms. I have to go around testing them intentionally.

Likewise, though I just put my ear defenders on (they are painfully
lound) and press the test switch on the Locate/Test/Silence switch
box and walk around rather than poking each one with a stick.

Or perhaps my cooking's got better.

The only thing that sets mine off is plumbing soldering. Or very
occasionally if I griddle-pan chargrill several chicken breasts and
forget to open a door for the duration.

Hum, kitchen ones ought to the "rate of rise" rather than "smoke"
detectors.



Domestic kitchens would normally be fixed temperature heat detectors and
not smoke alarms or rate of rise heat detectors.

--
Adam

On 22/11/2018 21:40, Robin wrote:
On 22/11/2018 19:14, ARW wrote:
OK so not DIY but some here do find such info interesting.

I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke
in the hallway (as per regs when they were built in 1994)

Out of the 16 I have tested 8 of them have either had the MCB to the
smokes turned off and the battery removed, the mains disconnected at
the smoke and the battery removed or the smoke heads have been removed.


I accept that the tenants have probably done some of this DIY
themselves to save buying a new battery.

However the most disturbing one is a flat that a tenant moved into 4
weeks ago. The mains had been disconnected from the smoke, taped up
and shoved into the ceiling as well as the battery having been
removed. Almost certainly like that when she moved in 4 weeks ago.


It's a sad reflection on both landlord and tenants.Â* I can only hope the
EICR is for a new owner/agent who wants to do better and not just 'cos
the insurer wants one.



Both would get the same report.



--
Adam

On Friday, 23 November 2018 18:35:25 UTC, ARW wrote:
I will soon be installing a new 60 detector 8 zone bi wire fire alarm
system for the communal hallways.

I wasn't sure if it was all in one building. As it is, has the landlord considered a full building fire alarm system with C-Tec Hush Buttons in each flat?

https://www.c-tec.com/fire-alarm-anc...-protocol.html

Provides an individual HMO dwelling with its own 2-minute silence facility (to BS 5839-6/12.2b) & 15-minute isolate facility (to BS 5839-6/12.2a).

Effectively stops the tenants permanently disabling any detectors as any faults will show up on the panel (and if the panel has an autodialler the landlord can be informed immediately and take appropriate action).

Unless fire compartmentation supports a 'stay put' policy then a full building fire alarm is probably required to get everyone out.

Sounder volume at the bedhead is likely to be an issue with a communal-areas-only system too.

Owain

On Fri, 23 Nov 2018 08:07:18 +0000 (GMT), "Dave Liquorice"
wrote:

On Thu, 22 Nov 2018 20:50:03 +0000, Max Demian wrote:

However the most disturbing one is a flat that a tenant moved into
4
weeks ago. The mains had been disconnected from the smoke, taped
up and
shoved into the ceiling as well as the battery having been
removed.
Almost certainly like that when she moved in 4 weeks ago.

Implying that the Land Lord didn't check the detector as part of any
"pre delivery inspection".

If they are linked burning toast in one flat will set them all off.

Which depending on the buildings construction (and modifications)
might be a good thing... However such a system has to be fairly
immune to false alarms from burning toast,


An alarm from burning toast is not a false alarm but the detector
doing its job and alerting the occupants that it has detected the
products of combustion (not necessarily smoke).

or the smokes will get
disabled. If the kitchen opens into the hallway the chances are it
won't be immune to false alarms. A hallway detector needs to be a
smoke based one not temperature.

Therein lies problem, Mrs Smith is a bit forgetfully and often singes
the bacon or overcooks the toast. Mr Jones the student doesn't
understand that letting the baked beans sit on the hob for 60 mins
will write off another saucepan and set off the alarms. Mr Williams
who works nights is seriously ****ed off by being constantly woken by
these events so whacks the detector until it stops making a noise. Mr
Abdul smokes a Hookah which regularly sets off the alarm because some
well meaning idiot put a detector in the lounge.etc. No one has yet
discovered a reliable "Hey this really is a fire you need to do
something!" alarm.

On 24/11/2018 17:49, Peter Parry wrote:
On Fri, 23 Nov 2018 08:07:18 +0000 (GMT), "Dave Liquorice"
wrote:

On Thu, 22 Nov 2018 20:50:03 +0000, Max Demian wrote:

However the most disturbing one is a flat that a tenant moved into
4
weeks ago. The mains had been disconnected from the smoke, taped
up and
shoved into the ceiling as well as the battery having been
removed.
Almost certainly like that when she moved in 4 weeks ago.

Implying that the Land Lord didn't check the detector as part of any
"pre delivery inspection".

If they are linked burning toast in one flat will set them all off.

Which depending on the buildings construction (and modifications)
might be a good thing... However such a system has to be fairly
immune to false alarms from burning toast,


An alarm from burning toast is not a false alarm but the detector
doing its job and alerting the occupants that it has detected the
products of combustion (not necessarily smoke).

....but only of interest to the owner of the toaster, not the entire
building.

--
Max Demian

On 23/11/2018 07:04, harry wrote:
On Friday, 23 November 2018 01:27:56 UTC, wrote:
On Thursday, 22 November 2018 21:40:58 UTC, Robin wrote:
On 22/11/2018 19:14, ARW wrote:
OK so not DIY but some here do find such info interesting.

I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

Out of the 16 I have tested 8 of them have either had the MCB to the
smokes turned off and the battery removed, the mains disconnected at the
smoke and the battery removed or the smoke heads have been removed.


I accept that the tenants have probably done some of this DIY themselves
to save buying a new battery.

However the most disturbing one is a flat that a tenant moved into 4
weeks ago. The mains had been disconnected from the smoke, taped up and
shoved into the ceiling as well as the battery having been removed.
Almost certainly like that when she moved in 4 weeks ago.


It's a sad reflection on both landlord and tenants. I can only hope the
EICR is for a new owner/agent who wants to do better and not just 'cos
the insurer wants one.


I suspect it's one of those systems that false alarms too frequently for the tenants to tolerate it. There are such systems out there. Last one I saw they had difficulty accessing the 'turn it off' function too. People get seriously fed up & detectors get disabled.

The companies that put systems in don't always do it adequately in this respect, leaving an LL that doesn't know how to solve it. Some systems are genuinely not livable with.

I'd ask the tenants about it and maybe flag this as a likely explanation, recommending it be made livable.


NT

Frequent false alarms lead to people ignoring them too.
Years ago ISTR an incident where people in a tower block ignored the fire alarm for this reason, it was a real fire and someone was killed.


The fire alarm went off on Monday when I was changing an emergency light
at a hotel. Everyone ignored it as they thought it was me that had set
the alarm off!!!!!!

Not one person (other than me) looked at the fire panel. Burnt toast in
the staff room was the cause.

--
Adam

On Saturday, 24 November 2018 17:49:47 UTC, Peter Parry wrote:
On Fri, 23 Nov 2018 08:07:18 +0000 (GMT), "Dave Liquorice"
wrote:
On Thu, 22 Nov 2018 20:50:03 +0000, Max Demian wrote:


However the most disturbing one is a flat that a tenant moved into
4
weeks ago. The mains had been disconnected from the smoke, taped
up and
shoved into the ceiling as well as the battery having been
removed.
Almost certainly like that when she moved in 4 weeks ago.

Implying that the Land Lord didn't check the detector as part of any
"pre delivery inspection".

If they are linked burning toast in one flat will set them all off.

Which depending on the buildings construction (and modifications)
might be a good thing... However such a system has to be fairly
immune to false alarms from burning toast,


An alarm from burning toast is not a false alarm but the detector
doing its job and alerting the occupants that it has detected the
products of combustion (not necessarily smoke).

it's a false alarm because there is no fire, no reason for the occupants to evacuate.

or the smokes will get
disabled. If the kitchen opens into the hallway the chances are it
won't be immune to false alarms. A hallway detector needs to be a
smoke based one not temperature.

Therein lies problem, Mrs Smith is a bit forgetfully and often singes
the bacon or overcooks the toast. Mr Jones the student doesn't
understand that letting the baked beans sit on the hob for 60 mins
will write off another saucepan and set off the alarms. Mr Williams
who works nights is seriously ****ed off by being constantly woken by
these events so whacks the detector until it stops making a noise. Mr
Abdul smokes a Hookah which regularly sets off the alarm because some
well meaning idiot put a detector in the lounge.etc. No one has yet
discovered a reliable "Hey this really is a fire you need to do
something!" alarm.

Yes they have. They're called heat alarms. The reason we also use ionisation & optical detectors is because they detect real fires much earlier in the process, giving much improved odds of survival. The downside is false alarms.

Perhaps the way forward might be a building-wide heat alarm system with local ionisation alarms that only warn locally. Maybe.

The other somewhat obvious thing is to position the alarms correctly, something many simply don't do. Advice to do that even got deleted from the wiki. Even an ionisation alarm doesn't false alarm in a kitchen if positioned well.


NT

On Saturday, 24 November 2018 19:32:06 UTC, ARW wrote:
On 23/11/2018 07:04, harry wrote:
On Friday, 23 November 2018 01:27:56 UTC, tabby wrote:
On Thursday, 22 November 2018 21:40:58 UTC, Robin wrote:
On 22/11/2018 19:14, ARW wrote:


OK so not DIY but some here do find such info interesting.

I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

Out of the 16 I have tested 8 of them have either had the MCB to the
smokes turned off and the battery removed, the mains disconnected at the
smoke and the battery removed or the smoke heads have been removed.


I accept that the tenants have probably done some of this DIY themselves
to save buying a new battery.

However the most disturbing one is a flat that a tenant moved into 4
weeks ago. The mains had been disconnected from the smoke, taped up and
shoved into the ceiling as well as the battery having been removed.
Almost certainly like that when she moved in 4 weeks ago.


It's a sad reflection on both landlord and tenants. I can only hope the
EICR is for a new owner/agent who wants to do better and not just 'cos
the insurer wants one.


I suspect it's one of those systems that false alarms too frequently for the tenants to tolerate it. There are such systems out there. Last one I saw they had difficulty accessing the 'turn it off' function too. People get seriously fed up & detectors get disabled.

The companies that put systems in don't always do it adequately in this respect, leaving an LL that doesn't know how to solve it. Some systems are genuinely not livable with.

I'd ask the tenants about it and maybe flag this as a likely explanation, recommending it be made livable.


NT

Frequent false alarms lead to people ignoring them too.
Years ago ISTR an incident where people in a tower block ignored the fire alarm for this reason, it was a real fire and someone was killed.


The fire alarm went off on Monday when I was changing an emergency light
at a hotel. Everyone ignored it as they thought it was me that had set
the alarm off!!!!!!

Not one person (other than me) looked at the fire panel. Burnt toast in
the staff room was the cause.

which indicates that they've stopped taking the system's (many false) alarms seriously.

On 24/11/2018 23:43, wrote:
On Saturday, 24 November 2018 19:32:06 UTC, ARW wrote:
On 23/11/2018 07:04, harry wrote:
On Friday, 23 November 2018 01:27:56 UTC, tabby wrote:
On Thursday, 22 November 2018 21:40:58 UTC, Robin wrote:
On 22/11/2018 19:14, ARW wrote:


OK so not DIY but some here do find such info interesting.

I am doing an EICR on a block of 38 rented flats all owned by the same
company. One and two bed flats with just a single mains powered smoke in
the hallway (as per regs when they were built in 1994)

Out of the 16 I have tested 8 of them have either had the MCB to the
smokes turned off and the battery removed, the mains disconnected at the
smoke and the battery removed or the smoke heads have been removed.


I accept that the tenants have probably done some of this DIY themselves
to save buying a new battery.

However the most disturbing one is a flat that a tenant moved into 4
weeks ago. The mains had been disconnected from the smoke, taped up and
shoved into the ceiling as well as the battery having been removed.
Almost certainly like that when she moved in 4 weeks ago.


It's a sad reflection on both landlord and tenants. I can only hope the
EICR is for a new owner/agent who wants to do better and not just 'cos
the insurer wants one.


I suspect it's one of those systems that false alarms too frequently for the tenants to tolerate it. There are such systems out there. Last one I saw they had difficulty accessing the 'turn it off' function too. People get seriously fed up & detectors get disabled.

The companies that put systems in don't always do it adequately in this respect, leaving an LL that doesn't know how to solve it. Some systems are genuinely not livable with.

I'd ask the tenants about it and maybe flag this as a likely explanation, recommending it be made livable.


NT

Frequent false alarms lead to people ignoring them too.
Years ago ISTR an incident where people in a tower block ignored the fire alarm for this reason, it was a real fire and someone was killed.


The fire alarm went off on Monday when I was changing an emergency light
at a hotel. Everyone ignored it as they thought it was me that had set
the alarm off!!!!!!

Not one person (other than me) looked at the fire panel. Burnt toast in
the staff room was the cause.

which indicates that they've stopped taking the system's (many false) alarms seriously.


They all came downstairs, saw me and just assumed that I had set the
alarm off.

--
Adam

On Sat, 24 Nov 2018 15:42:20 -0800 (PST), wrote:

On Saturday, 24 November 2018 17:49:47 UTC, Peter Parry wrote:
On Fri, 23 Nov 2018 08:07:18 +0000 (GMT), "Dave Liquorice"
wrote:
On Thu, 22 Nov 2018 20:50:03 +0000, Max Demian wrote:


However the most disturbing one is a flat that a tenant moved into
4
weeks ago. The mains had been disconnected from the smoke, taped
up and
shoved into the ceiling as well as the battery having been
removed.
Almost certainly like that when she moved in 4 weeks ago.

Implying that the Land Lord didn't check the detector as part of any
"pre delivery inspection".

If they are linked burning toast in one flat will set them all off.

Which depending on the buildings construction (and modifications)
might be a good thing... However such a system has to be fairly
immune to false alarms from burning toast,


An alarm from burning toast is not a false alarm but the detector
doing its job and alerting the occupants that it has detected the
products of combustion (not necessarily smoke).

it's a false alarm because there is no fire, no reason for the occupants to evacuate.

or the smokes will get
disabled. If the kitchen opens into the hallway the chances are it
won't be immune to false alarms. A hallway detector needs to be a
smoke based one not temperature.

Therein lies problem, Mrs Smith is a bit forgetfully and often singes
the bacon or overcooks the toast. Mr Jones the student doesn't
understand that letting the baked beans sit on the hob for 60 mins
will write off another saucepan and set off the alarms. Mr Williams
who works nights is seriously ****ed off by being constantly woken by
these events so whacks the detector until it stops making a noise. Mr
Abdul smokes a Hookah which regularly sets off the alarm because some
well meaning idiot put a detector in the lounge.etc. No one has yet
discovered a reliable "Hey this really is a fire you need to do
something!" alarm.

Yes they have. They're called heat alarms.

Neither fixed point trigger nor rate of rise heat alarms are adequate
for protecting occupants from common causes of fire. They belong only
in kitchens, utility rooms and garages where fires are likely to
start quickly and other detectors cannot be used. Rate of rise
detectors can also suffer nuisance alarms if for example they are
positioned above oven doors where the out rush of hot air when the
oven door is opened can cause them to trigger.

The reason we also use ionisation & optical detectors is because they detect real fires
much earlier in the process, giving much improved odds of survival. The downside is false alarms.

Neither optical nor ionisation detectors detect fires. Both detect
products of combustion. Quite often victims of fires are found away
from the source of the fire. Very few people burn to death, the fumes
(Carbon Monoxide in particular) kill them first and the influence of
heat is of minor importance.

Perhaps the way forward might be a building-wide heat alarm system with local ionisation alarms that only warn locally. Maybe.

Heat alarms trigger at about 60 deg C (fixed point) or for rate of
rise detectors by about 8 deg C per minute rise. Neither are useful
for life protection in common areas because by the time the fire is
sufficiently developed to trigger temperature alarms it will already
be producing lethal levels of fumes. Hence their only use is in small
confined areas such as kitchens where fires are likely to start and
either ionisation or optical alarms will routinely produce
unacceptable numbers of nuisance alarms or become compromised over
time by atmospheric contamination.

The other somewhat obvious thing is to position the alarms correctly, something many simply don't do.
Advice to do that even got deleted from the wiki. Even an ionisation alarm doesn't false alarm in a kitchen if positioned well.

Positioning is important but unless a kitchen is only used to warm
food and nothing will ever get burned an ionisation alarm is wholly
unsuitable in a kitchen no matter where it is installed. In a normal
two story construction the critical sensor is the one placed on the
ceiling at the top of the stairs. That will trigger first in about
80-90% of cases no matter where the fire starts. Even quite badly
placed alarms will work in most cases, just not as quickly as they
could.

Unfortunately fire protection by combustion detectors is one of the
fields where too many people believe that more = better and fail to
understand that if there are too many (and too many is a small number)
nuisance alarms then occupants will both ignore and later disable the
alarms. "I've put lots of sensors in so its much safer" often really
means "I've put lots of sensors in so its much less safe but I've
created a really good illusion of safety".

On 25/11/2018 13:14, Peter Parry wrote:

Unfortunately fire protection by combustion detectors is one of the
fields where too many people believe that more = better and fail to
understand that if there are too many (and too many is a small number)
nuisance alarms then occupants will both ignore and later disable the
alarms. "I've put lots of sensors in so its much safer" often really
means "I've put lots of sensors in so its much less safe but I've
created a really good illusion of safety".


I agree with the message in the para. above. but wonder if some might
take it as an argument against multiple detectors per se. Eg I took the
view that smoke detectors were best placed in the usual circulation
spaces which here gave 3 (above stairs, rear landing and downstairs
gall) and in rooms where electrical kit was routinely left on and
unattended which gave another 3. Most people think that's a lot in a 3
bed terrace house. The more so as 2 are only 2m apart. But there's a
closed door between them so I reckoned it was a price worth paying for
earlier warnings. And we've had perhaps 3 nuisance alarms in 10+ years
- and that includes those from neighbours' summer barbecues


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

On Sun, 25 Nov 2018 14:20:21 +0000, Robin wrote:

On 25/11/2018 13:14, Peter Parry wrote:

Unfortunately fire protection by combustion detectors is one of the
fields where too many people believe that more = better and fail to
understand that if there are too many (and too many is a small number)
nuisance alarms then occupants will both ignore and later disable the
alarms. "I've put lots of sensors in so its much safer" often really
means "I've put lots of sensors in so its much less safe but I've
created a really good illusion of safety".


I agree with the message in the para. above. but wonder if some might
take it as an argument against multiple detectors per se. Eg I took the
view that smoke detectors were best placed in the usual circulation
spaces which here gave 3 (above stairs, rear landing and downstairs
gall) and in rooms where electrical kit was routinely left on and
unattended which gave another 3. Most people think that's a lot in a 3
bed terrace house. The more so as 2 are only 2m apart. But there's a
closed door between them so I reckoned it was a price worth paying for
earlier warnings. And we've had perhaps 3 nuisance alarms in 10+ years
- and that includes those from neighbours' summer barbecues

When you are doing the installation yourself how many detectors you
use is your choice and you can add or subtract them as you wish. In
rented properties or for non-DIY installs it isn't as easy (or as
cheap).

The official guidance is still based upon presumptions from decades
ago when the two primary causes of domestic fires were chip pans and
smokers. Chip pans were usually heated on a hob and when they caught
fire the occupant often picked the burning pan up and ran towards the
door with it. After a bit they realised this hurt a lot so dropped
the pan making sure the fire and fuel were widely spread. Open pans
full of hot oil are less common these days but fires in the kitchen
are still the leading cause of domestic fires. Smokers still occupy
second place but cause far less fatalities because of the rules on
furnishing materials. The usual cause of death was Dad coming home
from the pub, sitting on the settee to light his fag and falling
asleep allowing it to drop down the side of the sofa and igniting the
sofa materials. The cyanide fumes these fires produced usually killed
the smoker before they ever realised there was a fire.

It doesn't pay to rely too heavily on smoke alarms alone, currently
about 20% of mains powered alarms will fail to detect a fire
sufficiently serious for fire service assistance to be needed. For
battery alarms the figure is about 40% (the difference being that
many battery powered detectors have no batteries fitted).

There is always going to be a balance between nuisance alarms and
detection. That balance will vary depending upon the occupants and
their activities. However, that is too complicated for simple
guidance which errs on the side of too many detectors and ignores the
fact that users will disable intrusive alarms. No simple guidance can
factor in that the occupant of one room can only sleep with ear plugs
and may miss an alarm outside their bedroom door or that another is
deaf or that another is a keen but not always effective cook.

Fortunately for DIYers the ideal balance of detectors can be achieved
on a case by case basis. Smoke dynamics and understanding that hot
air rises are easy to research at the superficial level need for
planning detector locations and an effective installation is easier
for a competent DIYer than it is for most professionals as they know
the way the house including occupants work.

On Sunday, 25 November 2018 13:14:40 UTC, Peter Parry wrote:
On Sat, 24 Nov 2018 15:42:20 -0800 (PST), tabbypurr wrote:
On Saturday, 24 November 2018 17:49:47 UTC, Peter Parry wrote:
On Fri, 23 Nov 2018 08:07:18 +0000 (GMT), "Dave Liquorice"
wrote:
On Thu, 22 Nov 2018 20:50:03 +0000, Max Demian wrote:


However the most disturbing one is a flat that a tenant moved into
4
weeks ago. The mains had been disconnected from the smoke, taped
up and
shoved into the ceiling as well as the battery having been
removed.
Almost certainly like that when she moved in 4 weeks ago.

Implying that the Land Lord didn't check the detector as part of any
"pre delivery inspection".

If they are linked burning toast in one flat will set them all off.

Which depending on the buildings construction (and modifications)
might be a good thing... However such a system has to be fairly
immune to false alarms from burning toast,


An alarm from burning toast is not a false alarm but the detector
doing its job and alerting the occupants that it has detected the
products of combustion (not necessarily smoke).

it's a false alarm because there is no fire, no reason for the occupants to evacuate.

or the smokes will get
disabled. If the kitchen opens into the hallway the chances are it
won't be immune to false alarms. A hallway detector needs to be a
smoke based one not temperature.

Therein lies problem, Mrs Smith is a bit forgetfully and often singes
the bacon or overcooks the toast. Mr Jones the student doesn't
understand that letting the baked beans sit on the hob for 60 mins
will write off another saucepan and set off the alarms. Mr Williams
who works nights is seriously ****ed off by being constantly woken by
these events so whacks the detector until it stops making a noise. Mr
Abdul smokes a Hookah which regularly sets off the alarm because some
well meaning idiot put a detector in the lounge.etc. No one has yet
discovered a reliable "Hey this really is a fire you need to do
something!" alarm.

Yes they have. They're called heat alarms.

Neither fixed point trigger nor rate of rise heat alarms are adequate
for protecting occupants from common causes of fire. They belong only
in kitchens, utility rooms and garages where fires are likely to
start quickly and other detectors cannot be used. Rate of rise
detectors can also suffer nuisance alarms if for example they are
positioned above oven doors where the out rush of hot air when the
oven door is opened can cause them to trigger.

The reason we also use ionisation & optical detectors is because they detect real fires
much earlier in the process, giving much improved odds of survival. The downside is false alarms.

Neither optical nor ionisation detectors detect fires. Both detect
products of combustion. Quite often victims of fires are found away
from the source of the fire. Very few people burn to death, the fumes
(Carbon Monoxide in particular) kill them first and the influence of
heat is of minor importance.

Perhaps the way forward might be a building-wide heat alarm system with local ionisation alarms that only warn locally. Maybe.

Heat alarms trigger at about 60 deg C (fixed point) or for rate of
rise detectors by about 8 deg C per minute rise. Neither are useful
for life protection in common areas because by the time the fire is
sufficiently developed to trigger temperature alarms it will already
be producing lethal levels of fumes. Hence their only use is in small
confined areas such as kitchens where fires are likely to start and
either ionisation or optical alarms will routinely produce
unacceptable numbers of nuisance alarms or become compromised over
time by atmospheric contamination.

The other somewhat obvious thing is to position the alarms correctly, something many simply don't do.
Advice to do that even got deleted from the wiki. Even an ionisation alarm doesn't false alarm in a kitchen if positioned well.

Positioning is important but unless a kitchen is only used to warm
food and nothing will ever get burned an ionisation alarm is wholly
unsuitable in a kitchen no matter where it is installed. In a normal
two story construction the critical sensor is the one placed on the
ceiling at the top of the stairs. That will trigger first in about
80-90% of cases no matter where the fire starts. Even quite badly
placed alarms will work in most cases, just not as quickly as they
could.

Unfortunately fire protection by combustion detectors is one of the
fields where too many people believe that more = better and fail to
understand that if there are too many (and too many is a small number)
nuisance alarms then occupants will both ignore and later disable the
alarms. "I've put lots of sensors in so its much safer" often really
means "I've put lots of sensors in so its much less safe but I've
created a really good illusion of safety".

You and most people are wrong on one point. Ionisation alarms can cover kitchens with no significant false alarms IF positioned correctly. Obviously 'correctly' there means something different than for other alarm types or in other locations.


NT

On Sunday, 25 November 2018 16:44:42 UTC, Peter Parry wrote:

When you are doing the installation yourself how many detectors you
use is your choice and you can add or subtract them as you wish. In
rented properties or for non-DIY installs it isn't as easy (or as
cheap).

The official guidance is still based upon presumptions from decades
ago when the two primary causes of domestic fires were chip pans and
smokers. Chip pans were usually heated on a hob and when they caught
fire the occupant often picked the burning pan up and ran towards the
door with it. After a bit they realised this hurt a lot so dropped
the pan making sure the fire and fuel were widely spread. Open pans
full of hot oil are less common these days but fires in the kitchen
are still the leading cause of domestic fires. Smokers still occupy
second place but cause far less fatalities because of the rules on
furnishing materials. The usual cause of death was Dad coming home
from the pub, sitting on the settee to light his fag and falling
asleep allowing it to drop down the side of the sofa and igniting the
sofa materials. The cyanide fumes these fires produced usually killed
the smoker before they ever realised there was a fire.

It doesn't pay to rely too heavily on smoke alarms alone, currently
about 20% of mains powered alarms will fail to detect a fire
sufficiently serious for fire service assistance to be needed. For
battery alarms the figure is about 40% (the difference being that
many battery powered detectors have no batteries fitted).

There is always going to be a balance between nuisance alarms and
detection. That balance will vary depending upon the occupants and
their activities. However, that is too complicated for simple
guidance which errs on the side of too many detectors and ignores the
fact that users will disable intrusive alarms. No simple guidance can
factor in that the occupant of one room can only sleep with ear plugs
and may miss an alarm outside their bedroom door or that another is
deaf or that another is a keen but not always effective cook.

Fortunately for DIYers the ideal balance of detectors can be achieved
on a case by case basis. Smoke dynamics and understanding that hot
air rises are easy to research at the superficial level need for
planning detector locations and an effective installation is easier
for a competent DIYer than it is for most professionals as they know
the way the house including occupants work.

I fit a lot more detectors than required for one simple reason. Whatever room/area a fire starts in, if there's a detector in there it's going to alarm much sooner than if there isn't. And time is critical to survival.

Ionisation is the type that detects the fastest on the whole. But if one produces repeat false alarms it needs replacing with something less hairtriggery. Failure to do so results in people ignoring then disabling. The legal requirements fail to address that, resulting in nonfunctioning systems sometimes.


NT

On 25/11/2018 18:11, wrote:
On Sunday, 25 November 2018 13:14:40 UTC, Peter Parry wrote:
On Sat, 24 Nov 2018 15:42:20 -0800 (PST), tabbypurr wrote:
On Saturday, 24 November 2018 17:49:47 UTC, Peter Parry wrote:
On Fri, 23 Nov 2018 08:07:18 +0000 (GMT), "Dave Liquorice"
wrote:
On Thu, 22 Nov 2018 20:50:03 +0000, Max Demian wrote:


However the most disturbing one is a flat that a tenant moved into
4
weeks ago. The mains had been disconnected from the smoke, taped
up and
shoved into the ceiling as well as the battery having been
removed.
Almost certainly like that when she moved in 4 weeks ago.

Implying that the Land Lord didn't check the detector as part of any
"pre delivery inspection".

If they are linked burning toast in one flat will set them all off.

Which depending on the buildings construction (and modifications)
might be a good thing... However such a system has to be fairly
immune to false alarms from burning toast,


An alarm from burning toast is not a false alarm but the detector
doing its job and alerting the occupants that it has detected the
products of combustion (not necessarily smoke).

it's a false alarm because there is no fire, no reason for the occupants to evacuate.

or the smokes will get
disabled. If the kitchen opens into the hallway the chances are it
won't be immune to false alarms. A hallway detector needs to be a
smoke based one not temperature.

Therein lies problem, Mrs Smith is a bit forgetfully and often singes
the bacon or overcooks the toast. Mr Jones the student doesn't
understand that letting the baked beans sit on the hob for 60 mins
will write off another saucepan and set off the alarms. Mr Williams
who works nights is seriously ****ed off by being constantly woken by
these events so whacks the detector until it stops making a noise. Mr
Abdul smokes a Hookah which regularly sets off the alarm because some
well meaning idiot put a detector in the lounge.etc. No one has yet
discovered a reliable "Hey this really is a fire you need to do
something!" alarm.

Yes they have. They're called heat alarms.

Neither fixed point trigger nor rate of rise heat alarms are adequate
for protecting occupants from common causes of fire. They belong only
in kitchens, utility rooms and garages where fires are likely to
start quickly and other detectors cannot be used. Rate of rise
detectors can also suffer nuisance alarms if for example they are
positioned above oven doors where the out rush of hot air when the
oven door is opened can cause them to trigger.

The reason we also use ionisation & optical detectors is because they detect real fires
much earlier in the process, giving much improved odds of survival. The downside is false alarms.

Neither optical nor ionisation detectors detect fires. Both detect
products of combustion. Quite often victims of fires are found away
from the source of the fire. Very few people burn to death, the fumes
(Carbon Monoxide in particular) kill them first and the influence of
heat is of minor importance.

Perhaps the way forward might be a building-wide heat alarm system with local ionisation alarms that only warn locally. Maybe.

Heat alarms trigger at about 60 deg C (fixed point) or for rate of
rise detectors by about 8 deg C per minute rise. Neither are useful
for life protection in common areas because by the time the fire is
sufficiently developed to trigger temperature alarms it will already
be producing lethal levels of fumes. Hence their only use is in small
confined areas such as kitchens where fires are likely to start and
either ionisation or optical alarms will routinely produce
unacceptable numbers of nuisance alarms or become compromised over
time by atmospheric contamination.

The other somewhat obvious thing is to position the alarms correctly, something many simply don't do.
Advice to do that even got deleted from the wiki. Even an ionisation alarm doesn't false alarm in a kitchen if positioned well.

Positioning is important but unless a kitchen is only used to warm
food and nothing will ever get burned an ionisation alarm is wholly
unsuitable in a kitchen no matter where it is installed. In a normal
two story construction the critical sensor is the one placed on the
ceiling at the top of the stairs. That will trigger first in about
80-90% of cases no matter where the fire starts. Even quite badly
placed alarms will work in most cases, just not as quickly as they
could.

Unfortunately fire protection by combustion detectors is one of the
fields where too many people believe that more = better and fail to
understand that if there are too many (and too many is a small number)
nuisance alarms then occupants will both ignore and later disable the
alarms. "I've put lots of sensors in so its much safer" often really
means "I've put lots of sensors in so its much less safe but I've
created a really good illusion of safety".

You and most people are wrong on one point. Ionisation alarms can cover kitchens with no significant false alarms IF positioned correctly. Obviously 'correctly' there means something different than for other alarm types or in other locations.




That goes against the advice from every manufacturer.


--
Adam

On 25/11/2018 18:11, wrote:

You and most people are wrong on one point. Ionisation alarms can cover kitchens with no significant false alarms IF positioned correctly. Obviously 'correctly' there means something different than for other alarm types or in other locations.



Do you do much cooking?


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

On Sunday, 25 November 2018 18:59:42 UTC, ARW wrote:
On 25/11/2018 18:11, tabbypurr wrote:

You and most people are wrong on one point. Ionisation alarms can cover kitchens with no significant false alarms IF positioned correctly. Obviously 'correctly' there means something different than for other alarm types or in other locations.

That goes against the advice from every manufacturer.

It certainly works well.
Commercial installers of course want to stick something in & forget it, and that's who such advice is aimed at. But an ionisation alarm needs moving until it no longer false alarms.
And since the kitchen is the prime fire risk area, I'd rather have it ionised than heated.


NT

wrote in message
...
On Sunday, 25 November 2018 16:44:42 UTC, Peter Parry wrote:

When you are doing the installation yourself how many detectors you
use is your choice and you can add or subtract them as you wish. In
rented properties or for non-DIY installs it isn't as easy (or as
cheap).

The official guidance is still based upon presumptions from decades
ago when the two primary causes of domestic fires were chip pans and
smokers. Chip pans were usually heated on a hob and when they caught
fire the occupant often picked the burning pan up and ran towards the
door with it. After a bit they realised this hurt a lot so dropped
the pan making sure the fire and fuel were widely spread. Open pans
full of hot oil are less common these days but fires in the kitchen
are still the leading cause of domestic fires. Smokers still occupy
second place but cause far less fatalities because of the rules on
furnishing materials. The usual cause of death was Dad coming home
from the pub, sitting on the settee to light his fag and falling
asleep allowing it to drop down the side of the sofa and igniting the
sofa materials. The cyanide fumes these fires produced usually killed
the smoker before they ever realised there was a fire.

It doesn't pay to rely too heavily on smoke alarms alone, currently
about 20% of mains powered alarms will fail to detect a fire
sufficiently serious for fire service assistance to be needed. For
battery alarms the figure is about 40% (the difference being that
many battery powered detectors have no batteries fitted).

There is always going to be a balance between nuisance alarms and
detection. That balance will vary depending upon the occupants and
their activities. However, that is too complicated for simple
guidance which errs on the side of too many detectors and ignores the
fact that users will disable intrusive alarms. No simple guidance can
factor in that the occupant of one room can only sleep with ear plugs
and may miss an alarm outside their bedroom door or that another is
deaf or that another is a keen but not always effective cook.

Fortunately for DIYers the ideal balance of detectors can be achieved
on a case by case basis. Smoke dynamics and understanding that hot
air rises are easy to research at the superficial level need for
planning detector locations and an effective installation is easier
for a competent DIYer than it is for most professionals as they know
the way the house including occupants work.

I fit a lot more detectors than required for one simple reason.
Whatever room/area a fire starts in, if there's a detector in
there it's going to alarm much sooner than if there isn't.
And time is critical to survival.

Not necessarily. All my rooms except the dunnys and
bathrooms have at least one patio door to the outside
so even if it takes a while before an alarm goes off, its
trivial to just use the patio door to get out.

And even you would notice a fire starting in
a dunny or bathroom when you are in there.

Ionisation is the type that detects the fastest on the whole.
But if one produces repeat false alarms it needs replacing
with something less hairtriggery. Failure to do so results in
people ignoring then disabling. The legal requirements fail to
address that, resulting in nonfunctioning systems sometimes.

On 25/11/2018 18:18, wrote:
On Sunday, 25 November 2018 16:44:42 UTC, Peter Parry wrote:

When you are doing the installation yourself how many detectors you
use is your choice and you can add or subtract them as you wish. In
rented properties or for non-DIY installs it isn't as easy (or as
cheap).

The official guidance is still based upon presumptions from decades
ago when the two primary causes of domestic fires were chip pans and
smokers. Chip pans were usually heated on a hob and when they caught
fire the occupant often picked the burning pan up and ran towards the
door with it. After a bit they realised this hurt a lot so dropped
the pan making sure the fire and fuel were widely spread. Open pans
full of hot oil are less common these days but fires in the kitchen
are still the leading cause of domestic fires. Smokers still occupy
second place but cause far less fatalities because of the rules on
furnishing materials. The usual cause of death was Dad coming home
from the pub, sitting on the settee to light his fag and falling
asleep allowing it to drop down the side of the sofa and igniting the
sofa materials. The cyanide fumes these fires produced usually killed
the smoker before they ever realised there was a fire.

It doesn't pay to rely too heavily on smoke alarms alone, currently
about 20% of mains powered alarms will fail to detect a fire
sufficiently serious for fire service assistance to be needed. For
battery alarms the figure is about 40% (the difference being that
many battery powered detectors have no batteries fitted).

There is always going to be a balance between nuisance alarms and
detection. That balance will vary depending upon the occupants and
their activities. However, that is too complicated for simple
guidance which errs on the side of too many detectors and ignores the
fact that users will disable intrusive alarms. No simple guidance can
factor in that the occupant of one room can only sleep with ear plugs
and may miss an alarm outside their bedroom door or that another is
deaf or that another is a keen but not always effective cook.

Fortunately for DIYers the ideal balance of detectors can be achieved
on a case by case basis. Smoke dynamics and understanding that hot
air rises are easy to research at the superficial level need for
planning detector locations and an effective installation is easier
for a competent DIYer than it is for most professionals as they know
the way the house including occupants work.

I fit a lot more detectors than required for one simple reason. Whatever room/area a fire starts in, if there's a detector in there it's going to alarm much sooner than if there isn't. And time is critical to survival.

Ionisation is the type that detects the fastest on the whole. But if one produces repeat false alarms it needs replacing with something less hairtriggery. Failure to do so results in people ignoring then disabling. The legal requirements fail to address that, resulting in nonfunctioning systems sometimes.

I wonder why Aico one of the UKs biggest manufacturer of smoke alarms
are phasing out their ionisation smoke alarms then?




--
Adam

On 25/11/2018 18:18, wrote:
snip

Ionisation is the type that detects the fastest on the whole. But if one produces repeat false alarms it needs replacing with something less hairtriggery. Failure to do so results in people ignoring then disabling. The legal requirements fail to address that, resulting in nonfunctioning systems sometimes.



And your authority for that is?

Cf:

"Ionisation smoke alarms have traditionally been used throughout
properties for many years. Designed to react quickly to fast flaming
fires, ionisation smoke alarms are most sensitive to small particles.
When fires produce little or no smoke but the fuel is subject to rapid
combustion, the ionisation smoke alarm is the quickest to sense its
presence. These fires tend to originate from materials such as paper and
clothing. "


"Less prone to false alarms than ionisation, optical smoke alarms are
slightly quicker at detecting slow smouldering fires that tend to
produce a lot of smoke. Also known as photo-electric alarms, this quick
response time to smouldering fires is down to the optical smoke alarm's
high sensitivity to large particles in the air. The optical sensing
chamber effectively "sees" when smoke is present, as the large particles
block and cause an infrared light to scatter."

https://www.safelincs.co.uk/smoke-alarm-buying-guide/

+ similar views from others sources

And the main cause of death in domestic fires is smoke inhalation.

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

On Mon, 26 Nov 2018 06:15:17 +1100, cantankerous trolling geezer Rot Speed,
the auto-contradicting senile sociopath, blabbered, again:

I fit a lot more detectors than required for one simple reason.
Whatever room/area a fire starts in, if there's a detector in
there it's going to alarm much sooner than if there isn't.
And time is critical to survival.

Not necessarily.

ROTFLOL You just HAD to contradict again, eh, you abnormal senile idiot?

--
Kerr-Mudd,John addressing senile Rot:
"Auto-contradictor Rod is back! (in the KF)"
MID:

In message , ARW
writes
On 25/11/2018 18:11, wrote:
Unfortunately fire protection by combustion detectors is one of the
fields where too many people believe that more = better and fail to
understand that if there are too many (and too many is a small number)
nuisance alarms then occupants will both ignore and later disable the
alarms. "I've put lots of sensors in so its much safer" often really
means "I've put lots of sensors in so its much less safe but I've
created a really good illusion of safety".
You and most people are wrong on one point. Ionisation alarms can
cover kitchens with no significant false alarms IF positioned
correctly. Obviously 'correctly' there means something different than
for other alarm types or in other locations.




That goes against the advice from every manufacturer.

We seem to be going round this again:-)

Slightly sideways and pertinent to why detectors may be disabled.....
battery life?
Set of 3 linked detectors. Batteries all failed within 2 weeks after
about 6 months use! PP3s are not cheap!

--
Tim Lamb

"ARW" wrote in message
...
On 25/11/2018 18:18, wrote:
On Sunday, 25 November 2018 16:44:42 UTC, Peter Parry wrote:

When you are doing the installation yourself how many detectors you
use is your choice and you can add or subtract them as you wish. In
rented properties or for non-DIY installs it isn't as easy (or as
cheap).

The official guidance is still based upon presumptions from decades
ago when the two primary causes of domestic fires were chip pans and
smokers. Chip pans were usually heated on a hob and when they caught
fire the occupant often picked the burning pan up and ran towards the
door with it. After a bit they realised this hurt a lot so dropped
the pan making sure the fire and fuel were widely spread. Open pans
full of hot oil are less common these days but fires in the kitchen
are still the leading cause of domestic fires. Smokers still occupy
second place but cause far less fatalities because of the rules on
furnishing materials. The usual cause of death was Dad coming home
from the pub, sitting on the settee to light his fag and falling
asleep allowing it to drop down the side of the sofa and igniting the
sofa materials. The cyanide fumes these fires produced usually killed
the smoker before they ever realised there was a fire.

It doesn't pay to rely too heavily on smoke alarms alone, currently
about 20% of mains powered alarms will fail to detect a fire
sufficiently serious for fire service assistance to be needed. For
battery alarms the figure is about 40% (the difference being that
many battery powered detectors have no batteries fitted).

There is always going to be a balance between nuisance alarms and
detection. That balance will vary depending upon the occupants and
their activities. However, that is too complicated for simple
guidance which errs on the side of too many detectors and ignores the
fact that users will disable intrusive alarms. No simple guidance can
factor in that the occupant of one room can only sleep with ear plugs
and may miss an alarm outside their bedroom door or that another is
deaf or that another is a keen but not always effective cook.

Fortunately for DIYers the ideal balance of detectors can be achieved
on a case by case basis. Smoke dynamics and understanding that hot
air rises are easy to research at the superficial level need for
planning detector locations and an effective installation is easier
for a competent DIYer than it is for most professionals as they know
the way the house including occupants work.

I fit a lot more detectors than required for one simple reason. Whatever
room/area a fire starts in, if there's a detector in there it's going to
alarm much sooner than if there isn't. And time is critical to survival.

Ionisation is the type that detects the fastest on the whole. But if one
produces repeat false alarms it needs replacing with something less
hairtriggery. Failure to do so results in people ignoring then disabling.
The legal requirements fail to address that, resulting in nonfunctioning
systems sometimes.

I wonder why Aico one of the UKs biggest manufacturer of smoke alarms are
phasing out their ionisation smoke alarms then?

Some European countries, including France,[23] and some US
states and municipalities have banned the use of domestic ionic
smoke alarms because of concerns that they are not reliable
enough as compared to other technologies.[24] Where an
ionizing smoke detector has been the only detector, fires in
the early stages have not always been effectively detected.
https://en.wikipedia.org/wiki/Smoke_detector#Ionization

On 25/11/2018 20:55, Tim Lamb wrote:
In message , ARW
writes
On 25/11/2018 18:11, wrote:
Unfortunately fire protection by combustion detectorsÂ* is one of the
fields where too many people believe that more = better and fail to
understand that if there are too many (and too many is a small number)
nuisance alarms then occupants will both ignore and later disable the
alarms. "I've put lots of sensors in so its much safer" often really
means "I've put lots of sensors in so its much less safe but I've
created a really good illusion of safety".
Â*You and most people are wrong on one point. Ionisation alarms can
cover kitchens with no significant false alarms IF positioned
correctly. Obviously 'correctly' there means something different than
for other alarm types or in other locations.




That goes against the advice from every manufacturer.

We seem to be going round this again:-)

Slightly sideways and pertinent to why detectors may be disabled.....
battery life?
Set of 3 linked detectors. Batteries all failed within 2 weeks after
about 6 months use! PP3s are not cheap!

Seems a bit odd if they were alkaline.

Anyhow, have you considered NiMH? I've been running linked detectors
with NiMH PP3s for the c.8 years since the original Alkaline expired.
I've had to replace one or 2 of the NiMHs (from Lidl) but so long as I
can manage the ladders every 6 months[1] it's economical.

What I'm dithering over, with the detectors approaching their end of
life, are the pros and cons of alkaline battery vs rechargeable lithium.
The choice'd be easier if I knew my expiry date but that just shifts
it to another decision...


[1] for pre-emptive recharges: something that I don't begrudge after
the time it started beeping at 02:00 after a heavy night
--
Robin
reply-to address is (intended to be) valid

On 25/11/2018 20:55, Tim Lamb wrote:
In message , ARW
writes
On 25/11/2018 18:11, wrote:
Unfortunately fire protection by combustion detectorsÂ* is one of the
fields where too many people believe that more = better and fail to
understand that if there are too many (and too many is a small number)
nuisance alarms then occupants will both ignore and later disable the
alarms. "I've put lots of sensors in so its much safer" often really
means "I've put lots of sensors in so its much less safe but I've
created a really good illusion of safety".
Â*You and most people are wrong on one point. Ionisation alarms can
cover kitchens with no significant false alarms IF positioned
correctly. Obviously 'correctly' there means something different than
for other alarm types or in other locations.




That goes against the advice from every manufacturer.

We seem to be going round this again:-)

Slightly sideways and pertinent to why detectors may be disabled.....
battery life?
Set of 3 linked detectors. Batteries all failed within 2 weeks after
about 6 months use! PP3s are not cheap!


Lack of mains power?

I would expect 5 years for a normal mains powered with battery back up
smoke detector before the battery goes flat.


PP3s are about a quid unless you buy them at a petrol station.

--
Adam

In message , ARW
writes
On 25/11/2018 20:55, Tim Lamb wrote:
Slightly sideways and pertinent to why detectors may be
disabled..... battery life?
Set of 3 linked detectors. Batteries all failed within 2 weeks after
about 6 months use! PP3s are not cheap!


Lack of mains power?

I didn't install them! Trip is on at consumer unit.

I would expect 5 years for a normal mains powered with battery back up
smoke detector before the battery goes flat.

That's more like it.


PP3s are about a quid unless you buy them at a petrol station.

Huh. Tell Tesco.


--
Tim Lamb

On Sunday, 25 November 2018 21:44:03 UTC, ARW wrote:
PP3s are about a quid unless you buy them at a petrol station.

Exactly a quid from a quid shop, but I'm not sure I'd trust my life to them..

Messrs CPC's GP High Power Alkaline are £9.51/10

Ultralife Lithium Manganese 10 year shelf life are £6.75 *each*

Plus the VAT, of course.

Owain