sprinklers

[Guest]

At what height (floor to ceiling) do sprinklers become ineffective?

[Guest]

anything less than one metre

[Guest]

It depends what size of fire you can tolerate. If you want a rule of thumb, if you use normal (not fast response) heads, flame height will be half way from floor to ceiling before the head first operates. There is a vicious relationship between ceiling height and the point at which a heat detector (which is what the bulb or link in a sprinkler head is in effect). It is a 5/2 power law. On the other hand if the ceiling height is very high you can probably tolerate a larger fire in many circumstances because you are less likely to get flashover. An infinitely high ceiling is same as a fire in the open. You need to think of the fire safety objective and then decide.

[colin todd]

Oops I sent that last message. Was not trying to remainn anonymous. How come when you get these damn computer wallahs in to install a new server they mess everything up in all your existing settings. Would they like to fly in an aircraft that they have installled a new server in!!!!!!*******

[Chris Houston]

Colin,

Maybe your specification and audit of the work they did was faulty - have you considered employing a consultant to oversee the project? :lol:

[potter 2]

on the subject of sprinklers,i am just working on a school sprinkler presentation.I have info about accidental actuation being about 1 in 15 million chance.But has anyone got experience of deliberate actuation by vandal,has it occured in a school yet ,what was the outcome,was the student wet and therefore caught easy,Whats a good way to convince non-believers who think they will always be going off

[Chris Houston]

10 years ago all local authorities, and therefore most schools, bought their insurance from municipal mutual.  It went bust and Zurich Municipal took over.  Many of the staff remained.  Consequently the company I work for insure the vast majority of schools in the UK and have done for some time.  None of us are aware of a single incident where a sprinkler head has been vanadlised in a school.

If vanadlism is a worry, just intall recessed heads.

The insurance company will pay for the water damage anyway, read the other thread in the forum to see the other MAJOR benefits.

If sprinker systems are good enough for many of our finest museums and libraries in the UK, I'd say the are good enough for the schools.

[Guest]

The 1 in 15000000m is not accidental operation. Its the failure rate for sprinkler heads which I'm sure all will agree is pretty damn good really.
I am involved in a similar initiative for schools in my Brigade area.
There are many misconceptions about sprinklers as you know. As far as the issue about all going off at once, its just a question of education and explaining the principle of each head being an individual detector and the progressive nature of these types of sprinklers. This process has not been helped by ads that use sprinklers within them which show them all going off at once. The current LYNX shower gel advert being a case in point.
There is an excellent video on the WORMALD dvd that has been recently released. This really is a quite excellent disc and has loads of information on it.
If you want some further info on the approach I use then indicate in this thread and I'll get in touch. I'm not saying that my system is the best but I have secured agreements with all LEA's that I have spoken with.
Softly softly is the way I have found. Developing a partnership with interested parties and showing them the benefits around the table produces good results as is getting the right people to the table.
Good luck.

[Guest]

Sorry, meant to add that in my area there has not been any vandalism to the sprinklers. Wherever possible, concealed heads will be used. I am a member of the National Fire Sprinkler Network. We hold quarterly meetings around the country. There has never been any mention of vandalism anywhere. Period.
I guess from your post that you are from LA fire Authority. Does your Authority have a representative on this committee. Also think IRMP.

[potter 2]

dear guest,thanks for the offer,,please  send private e-mail with phone number,,access by my profile,look forward to speaking,, Chris ive e-mailed mark barry for assisstiance,,if hes still in your gang,,

[Chris Houston]

Mark's the man!

[Guest]

Chris, you wrote If sprinker systems are good enough for many of our finest museums and libraries in the UK, I'd say the are good enough for the schools

I would imagine that in your job, you visit a large No of Schools. So how can you compare the hostile environment of a School with the expected environment of a Library or Museum when it comes to deliberate actuation of sprinklers.

(Not a critisism - just a query)

Messy

[Chris Houston]

Messy,

Yes I can compare them:

Schools in the UK are subject to malicious fires on a very regular basis.  A typical UK school will have an arson attack every 12 years.  In the past 5 years the UK have lost £500 million of school to arsonists.   Clearly this is unacceptable and something ought to be done.  It's rare to visit a school that does not have to spend at least a few thousand pounds every year repairing vandalism.

Despite this, the collective experience of the department I work for (who have been insuring the vast majority of schools in the UK and have records going back over 26 years) are not aware of a single issue of vandalism to a sprinkler system in a school or anywhere else for that matter.

Vandalism can be avoided by recessed heads.  If there was an issue of vandalism, the damage would only be around the vandalised head, nothing could cause it all to go off as some people imagine.  And even if a system was damaged, the insureres would inevitably cover the bill.

I'm not aware of any recent malicious fires in Museums, although due to their valuable contents and buildings, they are often sprinkler protected.

[Chris Houston]

PS What I meant when I said if they were good enough for our finest museums, then they ought to be good enough for the schools is:  If our museum curators are happy with the unwanted activation risk, then our head teachers ought to be.  

I think the problem is that too many people have seen TV adds and films where they see all the heads going off at once, and they think that is what happens in a fire.

I had a customer tell me this week that he didn't want sprinkers in his organisation because it might drown the animals.  I had to tell him that by the time it had activated, they would most probably be char grilled.  Again, they assumed that all heads activate at once.

[Guest]

Potter2, sorry I havnt replied yet. Having trouble logging on but working on it.