Extinguishers in sprinklered buildings

[kurnal]

Hi everybody
Just sorting out a strategy for a clients 48,000 sq m warehouse with 12m high racking, mixed stock in cardboard cartons. Its got life safety sprinklers in order to protect the business continuity and stock ( but not in rack sprinklers).
(yes I know but I have inherited it like this).

I recognise the importance of also providing fire extinguishers for knock down of small fires before they become big enough for the sprinklers to operate but the client would prefer not to  have to invest in what works out at something between one 3120A or  240 13A units !

I can't think of a good reason not to follow BS5306 in this case- especially in view of the RRO. Does anybody have an alternate view please?
Thanks

[Chris Houston]

No.  I think you should provide as many extinguishers as you would have to without the sprinklers.  

Less mess with an extinguisher should there be a fire
Cheaper to refill a sprinkler
A human with a fire extinguisher might react quicker than a sprinkler system
Your insurers might require it
What better way of demonstrating you have protected your employees other than to provide it as per the BS

Also, see below!

http://news.bbc.co.uk/1/hi/england/leicestershire/4445808.stm

[AnthonyB]

I would gather that you do not have hose reels or an easy way of installing them.

You still need to provide extinguishers as sprinklers have never had a discounting factor on numbers and in dealings with enforcement bodies over very big sprinklered warehouses they've required the correct number that became v expensive for one occupier (especially based on where he was buying his from)

If the risk & environment doesn't preclude the use of Powder then use a good make of ABC Powder (70%+ MAP content) as these have a 43A rating.

Even if the risk and environment lends itself more to water based extinguishers I can half your extinguisher numbers in one fell swoop - use 27A rated extinguishers.

One of the reasons that the extinguisher floor requirements were changed from Capacity v Floor area was because different technology and agents had very different results (as seen with different blends of powder or comparing 2 gallon chemical foam with 2 gallon mechanical foam) and thus the fire rating system was born.

As long as you meet the 30 metre rule you can use a lesser number of higher rated extinguishers to achieve your floor rating. 27A rated 6 litre foam extinguishers are available that combine a synthetic AFFF with a wetting agent to give the high rating - one supermarket chain halved the extinguishers in it's stores nationwide when it moved over to EN3 models by doing this.

based on your floor rating you could reduce your extinguishers fom 240 to 116 usiing 27A rated units that would cost under 7k
Using 43A rated Powder it would shrink to 73 extinguishers at under 4.5k

If you want to more about finding these extinguishers rather than purely technical questions, please PM me

[jasper]

I also usually spec extinguishers to be attached to the fork-lifts (if they have them) as these are mobile sources of ignition

[AnthonyB]

Good point & one that is being adressed more and more. Depending on the type of truck either AFFF or Powder is used, although I did see one place using CO2 extinguishers with transport brackets on their electric FLT's - a bit bulky, but now a viable option with the return of the 1kilo CO2

[Apollo_SG]

what we do as a practise is to remove the one of the levels in the rack and plant a cabinet to house both extinguisher + hosereel.

it is important for the client to know that your level of fire safety is formulated by

a) facilities for 1st aid fire-fighting (extinguishers + hosereel)
b) facilities for automatic fire protection (sprinklers)
c) facilities for automatic fire alarm + notification
d) facilities for fire-fighter search + rescue
e) facilities for evacuation (Exit signs, tactiles + emergency lighting)
f)  his fire mitigation policies.

most unreported fire are suppressed at incipient stages. and rack fire can and do grow substantial faster then ultra fast fires, due to the flue effect created between the racking shelves. re works by Lund University & NFPA.

I'm not sure what "life safety sprinklers" you have in mind but most of the industrial racking buildings are designed more to protect properties due to the large enclosed space, low occupancy, but general high consequential cost if the fire grows beyond the protected area of your sprinklers.

For us, we would propose ESFR sprinklers as a standard, because of it's inherent ability to suppress & extinguish fire.

[ian gough]

I can't see why legally you need to bother with any extinguishers - certainly not in view of existing fire safety legislation. Property protection, however, is another matter.

[Paul]

I wonder which insurance comany gave the ok to no fire extinguishers??  Surley not!!!

[AnthonyB]

Extinguishers have always been required to secure means of escape as oppose to property protection. Thats why they appeared in fire certificates whereas sprinklers (mainly a property protection installation) do not.

Again we see the decay of fire safety legislation being used to lower standards to save money.

[kurnal]

Thanks to you all for an interesting range of thought provoking replies.
My understanding of the RRO is that the role of fire fighting equipment has a new emphasis- its no longer just something you pick up and use to help support your use of the means of escape, the RRO approach is to recognise that if, by the use of FFE  you can stop a small fire becoming a big one this will protect:
Other building users- there will no longer be a fire from which need to escape
Firefighters- they won't have to risk their lives fighting the fire that you have extinguished
The environment- much less smoke and pollution from run off.
Business continuity  

So to some extent I can agree with Ians view that an employer has probably contributed to alll of these objectives ( and the old means of escape as well)  by providing a sprinkler system.
But how far do we go after this. Do we want a fire to grow to the extent of operating the sprinklers over say its assumed maximum area of operation? No, in my view we should be looking to provide extinguishers to ensure that the staff, who may possibly detect a fire long before even a fast response sprinkler head or a smoke detector operates, to intervene in the incipient stages.
And here is the crux in my opinion. Areas that are occupied by a reasonable number of staff- process, packing, despatch etc and who are using equipment to do their jobs are likely to be on the spot of an outbreak. BS5306 coverage is the answer here.
But in the warehouse picking area, there are  few risks, long travel distances and occasional occupancy but high value stock risk. Extinguishers every 200sq m cannot be good economics if theres only a 1 in 100 chance of there being someone around to operate it.

Thaks Jasper for your point about the FLT and I think that might be the answer I was looking for if it can be done- - the extinguisher travels round with the staff who may need to operate it, with extinguishers also each exit.  Elsewhere the sprinklers keep watch.
How does that sound?

Many thanks

[ian gough]

PSmith, I can't/wont tell you which one - but it's happened!

In high rack storage (and 12m is increasingly not exactly 'high-rack' any longer) fire extinguishers are pretty useless on their own. I say this because of the speed of flame spread up a rack and the distance employees may have to travel to find the fire (if their policy allows for this) and then safely fight it. In reality, only a hose reel will tackle a fire in the circumstances Kurnal describes - but then how practical is that for the building described?