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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Fire Safety => Topic started by: MC on October 19, 2007, 08:52:00 AM
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During a fire risk assessment at a clients property , it was noted on the previous FRA that they had concerns that there was no provisions for fighting electrical fires on each floor level. The property already has 1 x Foam and 1 x Water type on each level. Surely if in the event of a fire and the power was isolated , this would not be classed as an electrical fire, and the current extinguishers would be sufficient.
Many Thanks
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Problem you have is how does one know if the power is off. With electrical equipment one has always to make the assumption that it is live. In the spur of the moment it would be difficult to expect the average person to make a considered assessment as to whether it is safe or otherwise to use a media other than that as recommended.
When the alligators are snapping at your a@@e, it is difficult to remember that the reason you went into the pool in the first place was to pull the plug out .
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As part of the risk assessment you will identify electrical fires as a significant hazard and mitigate this risk by requiring Portable appliance testing to minimise the chances of a fire starting, minimise combustibles around it to prevent spread and in my opinion install a CO2 extinguisher to extinguish a fire. Water and foam are all well and good but the reality is the general workforce will not know how to isolate the buildings supply or be able to do it quick enough, and asking the general workforce to get under a table with a burning computer on top of it is unrealistic. In a modern world I would go with CO2 to complement Foam extinguishers.
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And not forgetting to have a number of nominated staff trained in the use of the fire extinguishers.
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I can't help remembering a demonstration at Moreton involving a 70mm jet and a 30,000 V grid. Even with the jet at maximum power no current at all passed back down the jet. Isn't it the case that we all get a little hysterical about the risk of electrocution from small electrical fires?
Or am I mistaken?
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Yes I agree we probably do get a bit hysterical about the risk, however the general rule of electrics and water don't mix has been well accepted and to try and change it for fire extinguishers will just spread confusion.
However the Moreton demo does come in useful when people start questioning the use of sprinkler protection with electrics and the use of water mist for computer suites.
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I can't help remembering a demonstration at Moreton involving a 70mm jet and a 30,000 V grid. Even with the jet at maximum power no current at all passed back down the jet. Isn't it the case that we all get a little hysterical about the risk of electrocution from small electrical fires?
Or am I mistaken?
The matter of the electrical conductivity of water is very well known to all and sundry. Pure water is non conductive. The conductivity is dependant on the level of impurities contained in the water and the distance from the electrical source. The higher the impurities the more conductive it is. The conductivity of sea water is greater than fresh water because of the higher level of impurities eg. salt.
The Morton demo is obviously safe because the branch is a distance away from the grid and the water is fresh and relatively clean. If you started to move towards the grid or used sea water you would measure an increase in conductivity at the branch and as you got closer it would eventually be fatal.
To use a water extinguisher on electrical equipment from a distance may be OK but who wants to try it?
Sprinklers may not neccessarily be a hazard because the conductivity of a spray or water droplets would be very low. The hazzard comes from the water getting into electrical equipment, just as it would by using jets.
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Many thanks for your help
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Late to the debate, but it must be remembered some electrical equipment can retain a charge after being switched off. Water & foam extinguishers in the main are not marked as suitable for electrical fires (with one or two smaller manufacturers being an exception) and thus you are going out on a limb if you use them against manufacturers guidance. In an emergency it's not always possible to be sure you've isolated the power & not always easy to do without risking putting the fire between you & the exit, or by talking to long (& plunging the place into darkness or EL levels only) by going to the main consumer unit.
Someone obviously messed up as what's the point in having water and foam together as you are duplicating cover. Where there is a live electrical risk you need, if you are going to tackle it, an extinguisher marked as fit for the risk, i.e. the lightning flash symbol, should be supplied. After all we are not splitting hairs over what's more effective, we are talking a mortal risk here that has been recognised in extinguisher design since the 1900's.
For safety's sake go with a non-conductive agent.
On a historical note in the 40's & 50's Nu Swifts Universal (Royal Navy) Extinguisher with a jet/spray nozzle was sold as safe up to 500V and British Rail replaced Halon with Foam (although that has been overturned since in most of their former & remaining properties with CO2 being added)
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I can't help remembering a demonstration at Moreton involving a 70mm jet and a 30,000 V grid. Even with the jet at maximum power no current at all passed back down the jet. Isn't it the case that we all get a little hysterical about the risk of electrocution from small electrical fires?
Or am I mistaken?
The matter of the electrical conductivity of water is very well known to all and sundry. Pure water is non conductive. The conductivity is dependant on the level of impurities contained in the water and the distance from the electrical source. The higher the impurities the more conductive it is. The conductivity of sea water is greater than fresh water because of the higher level of impurities eg. salt.
The Morton demo is obviously safe because the branch is a distance away from the grid and the water is fresh and relatively clean. If you started to move towards the grid or used sea water you would measure an increase in conductivity at the branch and as you got closer it would eventually be fatal.
To use a water extinguisher on electrical equipment from a distance may be OK but who wants to try it?
Yes, we do all know the conductive qualities of water. The explanation we were given for the lack of charge was that even a large jet under high pressure is still not a continuous line of water. The jet is beginning to break up as soon as it leaves the branch (even if not apparent to the naked eye). I am also assuming that the water contained in extinguishers is clean. (Again, am I mistaken?)
Is there any evidence or is it just 'something that everyone knows'?
I'm even less sure now that someone has mentioned the codes date back to 1900. Understanding of electricity was considerably less then. Could it be that the codes have just never been changed (rather like the 20m rule for turning circles -B5 max distance for horses walking backwards).
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Water used in extinguishers is 'as it comes' from the water supply on site -it could be mains fed, been stored in a tank first, been through lead pipes or anything.
It's certainly not pure and can contain all sorts of stuff. That is why with Water extinguishers designed especially for electrical fires, such as the Amerex Water Mist extinguisher, you are only supposed to use Distilled Water from sealed containers.
Extinguishers to EN3 (or more precisely their discharge) go through a 35kV conductivity test - if they fail they have conducted along the stream and they are marked as unsafe on electrical equipment.
Even those that pass (water & foam sprays usually) are not normally marked with the 'electrically safe' pictogram as there are too many factors that still present a risk not least the risk from pooled agent.
And although not the main factor they will cause more secondary damage to the electrical appliance than even powder does.
As extinguishers are now so ridiculously cheap these days (unless you are mug enough to use certain of the big national's for supply) is it worth splitting hairs over - just bung some CO2's in or if you aren't protecting escape stairs/corridors &/or a hotel/hospital/care home then replace the lot with factory sealed 2 kilo ABC Powders and save a fortune on purchase price and annual maintenance (which you wouldn't need)
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Of course it all begs the question 'where are you going to be free of electrical risks in any room. There are sockets, wall lights, and many other electrical pieces of equipment. So, should we only have dry powder or CO2 in buildings and no water based extinguishers. What a nightmare that would cause.....I rather like AFFF foam spray extinguishers instead of water. Lighter to handle, give a wider coverage, less likely to conduct electricty back to the user. Of course MCB's will add considerable protection as opposed to conventional fuses. Don't we all have a marvellous knack of making a science out of everything...sigh
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Quick point of concern is 'electrical fires' as for as long as I have ever studied the subject I have never found electricity to be combustible. What is mean t is much moire accurately described as a fire where live electricity is also present. Electricity can provide the spark, or heat, due to a fault to start a fire, but cannot be fuel for one.
if electical risks are identified then the risk assessment should not only look at the fire fighting provision, as that is further down the control measure lsit than removing the risk. Removal of the risk can be dealt with reasonably easily by ensuring that electrical circuits are protected by RCDs, these are designed to prevent the fire starting through electrical faults and to protect persons from electrocution should they come into contact with live circuits.
Do not think that a fire risk assessment means that only fire fighting/detection/signage are the available control measures. Dangerous, dangerous to stay on that line of thought. A fire rsik assessment is to identify risks and to suitable controls. Removal of the hazard/risk is always the best option and clearly the safest. So the RCD should be used first and extinguishers safe for use on live circuits only if this is not practicable. No electrical circuitry should be so unsound as not to be suitable for RCd fitment, indeed I suggest that the circuitry was probably not examined?
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Provided an electrical installation has been designed, installed and regulary tested in accordance with the IEE Regs (BS7671) then the risk of it being the cause of a fire is pretty low. Regular inspection/test needs specialised knowledge and equipment, so anyone carrying out a FRA on a premises should ask to see the latest Test Certificate for the electrical installation. If there isn't one the absence is a significant finding and should be appropriately commented on in the FRA.
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Provided an electrical installation has been designed, installed and regulary tested in accordance with the IEE Regs (BS7671) then the risk of it being the cause of a fire is pretty low. Regular inspection/test needs specialised knowledge and equipment, so anyone carrying out a FRA on a premises should ask to see the latest Test Certificate for the electrical installation. If there isn't one the absence is a significant finding and should be appropriately commented on in the FRA.
Don't overlook the portable appliances, including the ones that the staff have brought in from home.
Thermographic testing is a nice bonus to a full test.
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. So, should we only have dry powder or CO2 in buildings and no water based extinguishers. What a nightmare that would cause.....I rather like AFFF foam spray extinguishers instead of water. Lighter to handle, give a wider coverage, less likely to conduct electricty back to the user.
Strangely enough that's what most of the rest of the world, especially Europe, do. The ABC Powder extinguisher is the most commonly used, with CO2 for specialist risks - the US retain the APW (stored pressure water) in certain types of establishment where once a soda acid would have hung, but Powder is still most common. Plain water is rare in non US influenced countries, foam is rare too, any water based extinguishers that are in use (mostly in France) are water additive (in practice are akin to AFFF spray as are B-rated).
We are almost unique in our wide usage of the full range of agents, only former UK influenced countries like some South East Asian & Australasian ones seem to follow our pattern.
If you were not too bothered about property protection of electrical equipment then 'electrically safe' rated AFFF spray extinguishers in theory could cover most general risks with electrical kit available, after all:
- When AFFF 'light water' was first introduced in the UK as a 9 litre non aspirated spray by Thomas Glover in the early 80's it was marked specifically for electrical fires (although this was dropped by the mid 80's from labels)
- When British Railways saw in 1988/1990 that their vast use of Halon extinguishers should cease they chose, via Thorn, Thomas Glover AFFF extinguishers in 0.9, 1.75, 5.5 & 7.5 litre models to replace all uses of Halon and also all water extinguishers. So where a fire point of 8 litre water and 1.5 kg Halon was, a 7.5 litre AFFF replaced both. 1.5 & 5.5 kilo Halons on both derv & high voltage electrical trains with AFFF. CO2 never extended beyond it's traditional uses of kitchens/buffet cars, signal boxes, high voltage switchgear/substations, etc
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I cannot come to terms with dry powder extinguishers being operated inside buildings unless they are very big sheds with little delicate equipment.
Apart from the contamination of everything with dust, the tenability of the room is reduced both in terms of visibility and the choking effecy of the powder in addition to any productes of combustion.
For the typical workplace environment it isnt worth providing CO2 if all youve got is a pc in an office. But if you have a range of computers or other electrical equipment, printers, copiers and the like, and in particular if data stored on the equipment is of value then the CO2 gives you the best chance of
1- localising the fire to the point of origin, eg if the power supply of the pc is on fire only the use of a CO2 gives you any chance at all of putting out the fire AND saving the data off the hard drive
2- Not having to clean up one heck of a mess afterwards whether water, foam or powder. Downtime and consequential losses minimised with the use of clean CO2.
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Out of interest the least damaging extinguishant for a HDD is deionised water, which can be used to fill standard water extinguishers. CO2 will cause serious damage due to its extreme cold.
No one has followed up my point hat we should not be looking at the best extinguisher to deal with a fire involving live electricity, but should be removingt he current through correct risk assessment, by so doing the risks of electrical faults starting a fire are also delt with.
FORGET WHICH TYPE OF EXTINGUISHER DO A PROPER RISK ASSESSMENT AND IDENTIFY THE MOST APPROPRIATE CONTROL MEASURES. A Fire Risk assessessment is not a sales technique for extingusiher companies (i.e. you need a CO2 in every area along with your water based ones - pah!), it should be identifying each hazard, the sevrity of risk and the control measures. Live electrical equipment in case of a fire - OK well how do we remove the hazard and risks? Fite RCDs. Elecrtical faults may cause a fire, OK how dow e remove thr hazards and the risks? RCDs. Not CO2 extinguishers. Computer hard drive may be damaged through fire, or use of extinguishers, OK remove the risk altogether by having off site back ups, or regular on sit CD/DVD back up removed from premises each day etc. Again the type of extinguisher should not be the control first identified. Risk assessment is about determining the risks, the people and property likely to be affected and then the control measures best suited to them. Practicable being the test, not how whether the individual carrying out the risk assessment has a connection with another fire safety company (extinguisher sales), which is often the case, or has only knowledge of fire safety solutions - in which case they should not be carrying out risk assessments of any premises as the remit needs to look beyond those. Remember that, if the premises' electrical circuitry is not protected by RCDs then there is a risk to the persons and property through fire and electrocution, so not placing that control is missing a major point! If it is then why recommend extinguishers which should be unecessary?
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Sorry web connection problems meant I thought the post hadn't uploaded, so clicked for what turned out to be repeat - edited to this!
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I'm glad I sparked a useful debate. (Pause for laughter)
BTW I am only considering whether or not one could use an ordinary water extinguisher on a photocopier, for example, not advocating the use of jets in a sub-station.
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Out of interest the least damaging extinguishant for a HDD is deionised water, which can be used to fill standard water extinguishers. CO2 will cause serious damage due to its extreme cold.
No one has followed up my point hat we should not be looking at the best extinguisher to deal with a fire involving live electricity, but should be removingt he current through correct risk assessment, by so doing the risks of electrical faults starting a fire are also delt with.
FORGET WHICH TYPE OF EXTINGUISHER DO A PROPER RISK ASSESSMENT AND IDENTIFY THE MOST APPROPRIATE CONTROL MEASURES. A Fire Risk assessessment is not a sales technique for extingusiher companies (i.e. you need a CO2 in every area along with your water based ones - pah!), it should be identifying each hazard, the sevrity of risk and the control measures. Live electrical equipment in case of a fire - OK well how do we remove the hazard and risks? Fite RCDs. Elecrtical faults may cause a fire, OK how dow e remove thr hazards and the risks? RCDs. Not CO2 extinguishers. Computer hard drive may be damaged through fire, or use of extinguishers, OK remove the risk altogether by having off site back ups, or regular on sit CD/DVD back up removed from premises each day etc. Again the type of extinguisher should not be the control first identified. Risk assessment is about determining the risks, the people and property likely to be affected and then the control measures best suited to them. Practicable being the test, not how whether the individual carrying out the risk assessment has a connection with another fire safety company (extinguisher sales), which is often the case, or has only knowledge of fire safety solutions - in which case they should not be carrying out risk assessments of any premises as the remit needs to look beyond those. Remember that, if the premises' electrical circuitry is not protected by RCDs then there is a risk to the persons and property through fire and electrocution, so not placing that control is missing a major point! If it is then why recommend extinguishers which should be unecessary?
You can't tell business professionals how to run their business. Risk assess what you find and don't start advising whether to store information on-site or off-site! That is not our concern.
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Yes it is!!!!!!!!!
You have completely missed the point. Godsake where is the professionalism in the industry?
A risk, through fire, to the business is the loss of all their information. Business continuity may be destroyed along with their premises. If you are carrying out a risk assessment then this HAS to be taken into account, not to do so would be misconduct. If I was that business I would sue for sure.
So in your misguided RA world I would find that there is a risk to the business and then musn't think about advising my customer about it? I do not think so lawman.
If a business professional employs a professional, to fire risk assess their premises, they will expect a report on the hazards and risks found and control measures that are suitable. Nothing less would be sufficient, or acceptable. Should they, as business 'professionals. decide not to adopt the controls then that is their responsibilty and choice, but they MUST be informed of the MOST SUITABLE AND PRACTICABLE control measures.
I hate to think what sort of risk assessment you would carry out,something along the lines of "oh sorry mate I didn't tell you about the risks, that weren't in areas where fires safety solutions could be used as controls, because you are a business professional". Sounds oh so professional itself doesn't it? No it doesn't. I imagine your sales lealfets for any fire risk assessments would be worded as
'Assessments on the risks to your premsies and the people within them, excepting any areas of hazard and risk that you will already know about and be considering as business professionals. We will only be offering controls covering areas in which we think we can and these will mainly be where a fire safety solution can be used, such as buying some extinguishers off us'
I do hope so as that should ensure that you can't further the damage to the professionalism of the industry.
Lawman - Risk assess what YOU find and don't tell your customer how to best control them, great idea !!!!- please don't buy shared in this man's company - that's my risk assessment and control on it.
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Whilst I personally always include an overview of fire safety related business continuity issues in a fire risk assessment carried out under the RRO I do not regard it as mandatory- indeed I would be grateful if you would point out which article of the fire safety order says that I should?
Business continuity and disaster recovery are specalist areas of which fire safety is but one small element. I am happy to comment on this and any other fire related manner but I am clear that when I sell a fire risk assessment it is usually to meet the requirements of the fire safety legislation unless the client asks for something else.
For example just completed a specific risk assessment on electrical risks on a 20 acre industrial site focussed purely on business continuity and without regard to life safety issues. But that is unusual.
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There is no legal requirement to do so, kurnal. However if contracted to provide a Fire Risk Assessment to fail to note suitable control measures to any risk found would be professional negligence, not covered by the RRO. I am pleased that you do include business continuity, though cannot provide you with any legal requirement to do so under the RRO. Having said that there is nothing in the RRO says YOU need to identify any controls for risks, as legally these are still the responsibility of the responsible person, who is the business professional!
That you advise on the BC is an example of good practice, but if a customer employs you to give them a risk assessment, simply because they have to have one by law, does not excuse ignoring risks that fall outside the RRO as the customer should, rightly, expect that a professional would tell them anyway. The law of negligence would apply should that customer suffer a total loss and have not been advised about the risks to their business continuity. When carrying out a paid service the payer should expect that they recieve a full service. Nothing less.
The ignorance of the importance of business continuity displayed by The Lawman is indefensible. Anyone who sells Fire Risk Assessment without considering that there is more to this, for the customer, than the legal requirement, should not be trading.
Can you see the legal eagle's position? Well here is a possible law suit for negligence in risk assessment against The Lawman:
A business has collapsed due to a fire. They had employed The Lawman as Risk Assessor and had taken on all the recommended fire safety controls. However a lightning strike stated a fire, during a period when the premises were unoccupied. The fire alarm operated and all the extinguishers were available, however there was no one to use them and it took the fire service 15 minutes to arrive. The premises were well alight and were lost. The company, an internet/mail order supplier had no stock on site but lost all their customer details and website software. They were forced into administration and 10 people lost their jobs. Their insurance company, lawyers on behalf of the unemployed staff and adminstrators are suing as they have found out that there had ben a fire risk assessment. In this no mention was made of the risks to their business, or potential controls, by the damage that a fire could have on their business information. The Lawman is relying on the RRO as the reason that he did not make any recommendation about business continuity, as it does not cover this and after all the management were the professionals.
How do you think the case will go?
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In practice the scope and extent of the risk assessment is defined in the contract of sale and the methods statement.
There are dangers in partly covering some issues- for example whilst I may pick up on a particular hazard arising from a process as part of the general fire risk assessment, this comment does not absolve the employer from his duty to carry out a holistic process risk assessment which will be beyond my field of expertise.
If I cover a hazard without this caveat I am leaving my limited comments open to misinterpretation as being broader based than they are. The same goes for business continuity planning. There is a professional institution covering this topic.
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In practice the scope and extent of the risk assessment is defined in the contract of sale and the methods statement.
There are dangers in partly covering some issues- for example whilst I may pick up on a particular hazard arising from a process as part of the general fire risk assessment, this comment does not absolve the employer from his duty to carry out a holistic process risk assessment which will be beyond my field of expertise.
If I cover a hazard without this caveat I am leaving my limited comments open to misinterpretation as being broader based than they are. The same goes for business continuity planning. There is a professional institution covering this topic.
Where would you stop?
Someone preparing a FRA under the Fire (Scotland) Act 2005 can not possibly be expected to advise business professionals how to run/manage their business affairs other than where fire safety is compromised.
I agree Kurnal, where you stray into an avenue you are not competent in you will soon open yourself up to being legally liable for incompetence.
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Yes there is a business continuity thread separate to the fire safety one, however you must identify that fire can destroy computer hardware, that is not something that you could claim to be outside your field of knowledge and also fire damage to other contents/parts of the premises. So there is absolutley no excuse in not then identifying the control measures to reduce/remove the risks associated with the fire hazard. Not telling the customer that fire can damage their business by destroying their information is negligent, no less. Whatever FRA is being carried out ignoring that you have idenitified other risks, than are required under legislation to be controlled by the responsible person, is not professional. I refer again to my potential case. Your defence is weak, very weak, unless your contracts specifically say that only legislative areas will eb looked at and any other risks that you doscover will be ignored. I can't see many people being happy with that. I am amazed that you think it is acceptable to know that your customer is at risk of losing their business, because no controls are in place for information storage in the event of a fire, and are happy that you aren't goingt ot ell them, worse still that you would refer to legislation designed to force a level of RA to hide n behind on the basis that only those forced areas are to be reported on. Disgraceful, absolutley disgraceful. I do hope you are making loads of money from your half-hearted and half-done RAs as the businesses you have worked for may be seeking compensation later. I fail to see why you can't accept that it is good practice, and demonstrably professional to boot, to tell your customer about risks (that are after all due to fire) but beyond the legislative requirements. I bet you never recommend any extinguishers/signs/alarms that aren't actually REQUIRED because to have more is better, or because you make more money from them. Go on think about giving absolute basic, nothing more than is actually legally required, advice and see whether you think that is right either?
I do like the way you read kurnal's comments as being fuly supportive of yours, actually I read them to be supporting mine. He says there is danger in partly covering something and that by saying something he does not absolve the business form responsibility, that is equally true of your FRA by the way - what he does not say is that he would therefore not tell them at all, quite the opposite form my reading. In the case of back ups for computer information you would not be partly covering the issue at all, a quick question will determine if the information is critical to the business and if they have off site back ups already. From that a RA and control suggestion to carry out back ups is fully covering the risk. Simple. Indeed if you at the FPA Business Fire Risk Assessment guidance business continuity is clearly a part. Maybe the law doesn't require consideration of this, but bet your life your customer would have thought you would - especially post event if you never mentioned it - litigation would be in their minds for sure and I have little doubt that most judges would agree with them.
Where do you stop? Well you stop when you have identified all the risks from fire and their possible controls, that is what you were there to do, if you spot risks not connected with fire you mention them with the 'not my science' caveat, but fire is.
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The Lawman
i'm still waiting for you to tell us about the fire you mentioned that " killed 4 kids, locally "
Conqueror.