Fire extinguisher rating for Class A fires

[billthefire]

After using the formula of 1 water extinguisher per every 200 square metres to calculate the number of 13A rated fire extinguishers required, how is this formula affected by the installation of a water sprinkler system?

[FSO]

I was recently involved with a premises that did not have any portable extinguishers due to having a top of the range misting system fitted. Also a L1 system was fitted alongside AOVs and very good passive protection.
The risk assessment for the property (Resi care for naughty children), deemed it would be safer this way due to possible interfering with the extinguishers.

This was deemed acceptable providing contingency was put in place in the event of system maintenence and downtime. There were fire blankets in the kitchens.

First one I have ever come across.

Jay

[Chris Houston]

Bill,

On the assumption that you do not have "naughty children" you should provide fire extinguisher in exactly the same way as before.  

1 - your insurer will probably demand this
2 - you probably would prefer to put out a waste paper basket fire before it get's big enough for sprinklers to activate
3 - people will probably instinctivly try and put out tiny fires so you should give them the correct equipment to do this
4 - If someone's clothing is on fire, you need to be able to react to this - although a fire blanket will be the prefered option
5 - I think, but stand to be corrected, that the RR(FS)O requires occupiers to provide first aid fire fighting equipment.

[FSO]

Article 13 does indeed say that the RP must provide appropriate fire fighting equipment.

Of course this is the RRO being fluffy again and putting it down to the RP to risk assess what is appropriate.

However I do agree with Chris (apologies if my previous post was misleading) that it is still a good idea to have extinguishers fitted to the recommended standard for the above reasons.

Jay

[jokar]

Regarding FSO post above. what happens when the sprinklers are down for maintenance or repair, is there a contigency in place?

I agree with Chris although his point 5 is not strictly correct as Article 13 states where necessary with competent people, to paraphrase.  That is probably why using the FRA methodology FFE was excluded from the premises FSO describes.

[FSO]

Regarding FSO post above. what happens when the sprinklers are down for maintenance or repair, is there a contigency in place?

Indeed Jokar very valid point.

As mentioned in the previous post they had to prove contingency in those circumstances.

The staff did not seem very confident in the system due to no experience of it though.

[Dragonmaster]

Article 4(f)(ii) - General Fire Precautions require measures to mitigate the effects of a fire. Whilst a water mist system will acheive this, what about a small fire, say in a litter bin. Do you really want to wait for the mist system to activate (meaning an increase in the fire size) and use a lot more water causing a lot more damage?

We would always expect to find FFE in any premises, especially where there are staff, but accept that their locations were restricted to staff controlled areas e.g. office, staff bedroom, behind the bar in a pub etc

[FSO]

As you quite rightly say Dragonmaster Article 4(f)(ii) is already achieved through a water mist system. Remember the RR(FS)O is concerned with life safety only not property protection. That is for the insurance companies and property owners to worry about.
Where there are plenty of well maintained protection measures in place and a good management strategy (just like in my example), I would be happy that everybody could be evacuated in plenty of time.
Although FFE is very useful for extinguishing small fires we do not advise them in a private dwelling but appluade domestic sprinklers. I know there is a bit of difference in regard to training etc, but if there there are plenty of good protection measures in place why put people at risk.

I am an IO for a FRS and would love to see FFE everywhere complemented by sprinklers etc...

However in this non perscriptive risk based world that we now live in, could you be justified in asking for extra when technically that extra is not always needed?

I am sure that this has been discussed on here somewhere else, but it always gets me thinking.

Commercial sector vs FRS again ;-)

Jay

[Ken Taylor]

From the FRS point of view getting them out safely always seems to be the ultimate aim - but as far as employers are concerned, they usually like to see minimum disruption to business and a workplace remaining usable after an incident. Whilst there may well be legally acceptable FRAs without recourse to FFEs, the employer and his insurer's assessments of acceptable risk should take a wider perspective. If one of the extinguishers is out of action or declared u/s on inspection, the effect in terms of overall fire cover is likely to be small and a prudent employer will have a stock of spares for early replacement. If the sprinklers are down, the likely temporary replacement to enable work to safely continue is a supply of extinguishers.

[Chris Houston]

but if there there are plenty of good protection measures in place why put people at risk.

In what way is providing a fire extinguisher putting someones live at risk?!

Why do you not recommend them in people's homes?  I think you should!

When someone sees a small fire in their house, what do you think they will do? Walk away and phone the brigade, or try and put it out?  My experience is that most will try and put it out with what ever they have.  What better thing to have than a fire extinguisher?!

[AnthonyB]

Beware when trying to mathematically distribute extinguishers as you can come unstuck. The old days of 'x gallons water extinguisher for every z yards of floor' & ''a lbs of powder for b sq ft of liquid on fire' have gone as have when every water extinguisher was 13A.

Most decent 9 litre waters are now 21A, You can get 6 litre water additive extinguishers with a 34A rating, 6 litre foam additives with a 27A 183B rating, etc.

You take your floor area in sq metres, multiply by 0.065 and it gives your floor fire rating. You need to reach this figure with your extinguisher provision and using higher rated extinguishers reduces the number you need (good for client, bad for 'sell as many as I can con them into' suppliers), although you musn't forget the 30m rule (travel distance) or the caveat advising against using loads of small rated extinguishers or a small number of high rated extinguishers.

BS 5306-8 doesn't have a formula for down-rating provision where other active fire precautions are used and instead states specialist advice is required.

One example of reduced provision was in a large sprinklered warehouse with FLT's zipping around. It was decided that for the stored goods to be involved the fire would have to be well developed and better left to the sprinklers, so no point in providing the large number of A-rated extinguishers around the warehouse that would normally be required. Instead extinguishers were confined to likely sources of origin, such as each FLT, the charging station etc. More traditional provision was placed in the admin areas.

[FSO]

We will not advise people to have extinguishers within their home unless they are fully trained to use them. The reason why we do this is down to many accounted injuries caused by people becoming emotionally commited to trying to protect their property. The best advice we can give is the usual get out, stay out, get the fire service out. I would never advise anybody to tackle a fire as I would have their personal safety in mind. Let the insurers worry about the damage.
I understand that employers and insurers may take a different view to me, but obviously that is their desicion.

I would be happy with a good automatic system providing there were other measures to protect people, eg AFD,good passive protection and a good justified risk assessment.

I have personal experience of a fire fatality, where an employee decided he would return back into the premises and fight the fire using FFE. This person was trained to a good standard, but sometimes you cannot take away the 'Human Factor' out of the equation.

Obviously I understand there are many varying scenarios and situations out there where this idea would not be suitable, however I like healthy debate.

Thank you for your opinions.

Jay

[John Webb]

There is some arguement for having more extinguishers of 'small' (ie 6 litre) capacity rather than fewer of large (9/10 litre). It goes something like this:
(a) The smaller extinguisher is easier for one person to move due to it's smaller size and weight.
(b) People should always be told that there should be two of them together if any use of FFE is to be attempted.
(c) Two extinguishers applied simultaneously will achieve a higher rate of application of extinguishent than each used on its own, and thus has a greater prospect of putting out the fire before the extinguishers are empty.

The last point is one which I have hardly ever seen mentioned in training literature or films.

[Chris Houston]

Sorry to hear of the fatalisty, but I think anyone who left a building and then went back in to tackle appears not to be very well trained.

Essex fire service adviced that 90% of fires are put out without fire service involvement, I concur with this.  The reality is that fires happen all the time and people tend to deal with them without dialing 999.

People will use buckets of water and what ever comes to hand without being trained on how to tackle a fire in that manner.  A significant proportion of people, especially vulnerable ones who seem to be at a higher risk of fire, don't have insurance.

[kurnal]

I have often reduced provision of class A portable extinguishers in large sprinklered buildings subject to the knowledge and approval of the insurers.
In a large building balancing the formula class A rating with the manual handling considerations of large extinguishers and the total number required leads to silly levels of provision. I always try and stick to the 30m rule and often drop it to 50% provision- no more than two similar extinguishers at a fire point, no part of the floor area more than 30 m from a fire point, where possible fire points to include alarm call points and fire action notices. I have seen fire points with 6 or more identical extinguishers- wheres the point in that?