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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Fire Safety => Topic started by: saddlers on June 09, 2008, 10:54:15 AM
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Can anyone point me towards any relevant guidance on the suitability of sprinkler heads in commercial kitchens and the effect on fat fires. I know this may be a stupid question, but I seem to be struggling to quickly locate any guidance. Does the guidance lean more towards providing a localised suppression system, such as Ansul system.
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Ideally you would want both sprinklers and Ansul, but don't avoid putting sprinklers in kitchens just because there is deep frying going on. The fire brigade won't hesitate to apply water in large quantities to kichens on fire, if you are worrying about an injury risk to people in the kitchen - then don't by the time the sprinkers have activated they will not be standing about in the kitchen.
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Thanks Chris, my mind was saying that by the time the system activates, no-one should be close enough to be at risk, but bizarrely I have never come across this scenario before, so thought I would get a more informed opinion.
Input is really appreciated
Thanks
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I think they might put different temperature bulbs in kitchens, but I know I wouldn't be hanging around in a room that was 68 degrees hot. If I was, I'd be hoping for some water to start coming from the ceiling!
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I work for a company who instal Ansul systems, email me and i can give you our technical teams number, maybe they can help you with guidance material.
MC
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It might be worth looking at a water mist system. Due to the small size of the droplets this should not create a problem with the fat fire.
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My some years old and possibly out of date notes on sprinklers says:
(a) operating temp of head to be not more than 30deg C above the highest expected ambient
(b) where there are ovens and/or hot process ventilating hoods, sprinklers within 3m (plan) to be either the same as any sprinklers fitted to the oven or hood, or 141deg C, whichever is the lower.
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Generally commercial kitchens do not represent such a high fire risk as to warrant the installation of sprinklers in their own right. However it the building has sprinklers elsewhere for what ever reason- size, height, engineered solution etc then the sprinklers should also cover the kitchens.
If you are looking at the kitchen in isolation as a fire risk in an otherwise unsprinklered building then the ansul is the way to go. In fact even if there are existing sprinklers an ansul system for the cooking range would be a great way of reducing risk.
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High pressure water mist systems have been installed in many hundreds of kitchen applications. The advantage they offer over the Ansul system is speed of extinguishment, rapid cooling, clean and environmentally friendly. I have recently seen one company that has developed a stand alone pumped system that sits in nothing larger than a bread bin! it works and has passed live tests with the LPC and is going through the accreditation process. In the past these systems have relied on a one shot cylinder system arrangement.
One question I have for the Ansul folks. What does the end user do with the oil waste/foam mix when they dispose of it? A lot of restaurants, etc. have their used oil taken away to be made in to Bio fuel, once contaminated the oil is useless to them.
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I'm unconvinced that there is any significant environmental impact difference beween ansul and water. In the grand scheme of things this appears to be negligible to me.
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I would like to take this opportunity remind you of the forum rules regarding multiple posts....
*CivvyFSO runs off laughing
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And also of the spelling of 'negligible'.
*CivvyFSO slips
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Did I ever mention: one of the fun things about being Forum Admin is the fact I can change history? :lol:
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and you thought 1984 was fiction
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By changing history you may be influencing and changing the future too- scary.
if you hadnt changed history I would not have posted this and instead would have been in time to put a fiver on a cert at the bookies and I could have been on my way to being rich. So you owe me.
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Or did I save you a fiver?
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Chris, when a water mist system is used the water converts to steam (telling you how to suck eggs); this cools the oil and does not contaminate it. If there is any water left in the oil when it cools this will 'flash off' when the oil is heated again. In effect it is possible to continue to use the oil. When cooking oil is used in a fryer the flash point and auto ignition temperature gets lower and lower. This is caused by a build up in Free Fatty Acids (FFA's). It has been proven scientifically that FFA's are substantially reduced when water mist is applied.
In a nut shell, Ansul is a chemical that contaminates the oil; as such the oil must be replaced. How does the restaurant dispose of it? There are thousands of Ansul systems in use, so potentially the environmental impact could be huge. On top of the oil disposal you have to use chemicals to deep clean the fryer and kitchen, you also have to replace the oil when it is not necessary. No I am not an Echo warrior, live in a tent or drive a bio fuelled combi van. I take regular baths (at least once a year) and have normally named children, not Trix Frufru or Eco Star Boy.
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I know all this and still think its negligable. Kitchens use fossil fuels to generate heat, they produce varying amounts of waste oil/plastic/food. Having to dispose of some contaminated oil (most go through loads of oil anyway) as a one off event is such a drop in the ocean compared to the larger negative effect of even just that one kitchen and in the grand scheme of things, industrial kitchens are pretty low down the priority list of environmental problems.
How far to we take this? How do we measure it? How much fuel is used to make and tranport each systems components, how green are the factories where they were made? What was the carbonfootprint of the R&D to develop these systems? How recyclable are the system components?
I would guess that any system need only extinguish 1 fire to bring 100 times moreenvironmental benefit than all r&d, transport, disposal and all others negative effects. But I can't confirm this with and formulae. So I don't think splitting hairs between systems is necessary. Unless of course we can measure it. Can you?
Chris
(composter, recycler, greenpeace member and general environmental good guy)
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I know all this and still think its negligable. Kitchens use fossil fuels to generate heat, they produce varying amounts of waste oil/plastic/food. Having to dispose of some contaminated oil (most go through loads of oil anyway) as a one off event is such a drop in the ocean compared to the larger negative effect of even just that one kitchen and in the grand scheme of things, industrial kitchens are pretty low down the priority list of environmental problems.
How far to we take this? How do we measure it? How much fuel is used to make and tranport each systems components, how green are the factories where they were made? What was the carbonfootprint of the R&D to develop these systems? How recyclable are the system components?
I would guess that any system need only extinguish 1 fire to bring 100 times moreenvironmental benefit than all r&d, transport, disposal and all others negative effects. But I can't confirm this with and formulae. So I don't think splitting hairs between systems is necessary. Unless of course we can measure it. Can you?
Chris
(composter, recycler, greenpeace member and general environmental good guy)
Mr Houston for Prime Minister I say
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I was under the impression that cooking oil that had been on fire had an unpleasant taste that tainted the food and that this prevented it being used again? Or is this wrong? The local chippy say they get through about 50 gallons a week- though that was in a biofuel discussion so may not be factual.it seems a lot to me.
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Chris, I agree..
Kurnal, its the oil vapour that burns once it reaches its flash point not the oil unless the oil is extremely disgusting and has a scum on it that acts as a wick. Bring on global warming if it gives us better summers and colder winters....
Is there anybody out there who knows how many Ansul systems are discharged each year in the UK i.e recharging systems?