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UK diy (uk.d-i-y) For the discussion of all topics related to diy (do-it-yourself) in the UK. All levels of experience and proficency are welcome to join in to ask questions or offer solutions. |
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#1
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unvented gas fire
Probably not a DIY topic but I think there will be folks out there who
have an opinion. I need to move my gas fire to a new location as I'm rearranging the room layout. I'm limited as to where a balanced flue can go, and unless somebody has a good idea I don't think I will be able to use the existing chimney. The chimney is a line of hollow bricks going up the cavity wall ca 1980. I've seen several models of flueless fires which claim to be 100% efficient and deliver up to 3.5 KW, which would be adequate. I find it hard to accept the idea of filling up the room with CO2 as being a good thing, though I guess they must be approved and considered safe. Comments anyone? |
#2
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unvented gas fire
andyv wrote:
Probably not a DIY topic but I think there will be folks out there who have an opinion. I need to move my gas fire to a new location as I'm rearranging the room layout. I'm limited as to where a balanced flue can go, and unless somebody has a good idea I don't think I will be able to use the existing chimney. The chimney is a line of hollow bricks going up the cavity wall ca 1980. I've seen several models of flueless fires which claim to be 100% efficient and deliver up to 3.5 KW, which would be adequate. I find it hard to accept the idea of filling up the room with CO2 as being a good thing, though I guess they must be approved and considered safe. Comments anyone? They are safe given that they are fitted with a catalytic(sp?) converter, similar to those in cars. That said, I still wouldn't have one in a room without good ventilation, and by good ventilation I mean an unobstructed 9 inch by 6 inch permanent vent (not a sliding louvre type), overkill yes, but I doubt if it would be noticable with the heat that flueless fires give out. |
#3
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unvented gas fire
andyv wrote: Probably not a DIY topic but I think there will be folks out there who have an opinion. I need to move my gas fire to a new location as I'm rearranging the room layout. I'm limited as to where a balanced flue can go, and unless somebody has a good idea I don't think I will be able to use the existing chimney. The chimney is a line of hollow bricks going up the cavity wall ca 1980. I've seen several models of flueless fires which claim to be 100% efficient and deliver up to 3.5 KW, which would be adequate. I find it hard to accept the idea of filling up the room with CO2 as being a good thing, though I guess they must be approved and considered safe. Comments anyone? The catalytic converters should deal with any CO that's produced - that's the real nasty stuff. I guess the CO2 would be no different to a gas hob running..... |
#4
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unvented gas fire
andyv wrote:
Probably not a DIY topic but I think there will be folks out there who have an opinion. I need to move my gas fire to a new location as I'm rearranging the room layout. I'm limited as to where a balanced flue can go, and unless somebody has a good idea I don't think I will be able to use the existing chimney. The chimney is a line of hollow bricks going up the cavity wall ca 1980. I've seen several models of flueless fires which claim to be 100% efficient and deliver up to 3.5 KW, which would be adequate. I find it hard to accept the idea of filling up the room with CO2 as being a good thing, though I guess they must be approved and considered safe. Comments anyone? ventilation, i would be in agreement with phil on the overkill vent!, obviously you will have a window in the room that opens too. out of interest i would like a look at the manufacturers installation instructions if you do go ahead and fit one of these, just to find out if there is yet a 'common' way of installing/venting/room size etc |
#5
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unvented gas fire
I'm still undecided, but it's an interesting comment about gas cookers
as these usually vent straight into the kitchen. Not everybody has an extractor. A regular gas fire, such as I now have also probably vents some of its exhaust into the room too. |
#6
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unvented gas fire
The news groups are fine for getting some ideas about this, but I'd be
astounded if the installation notes for these appliances didn't exactly specify the minimum ventilation requirements, probably in relation to the size of the room they're installed in. |
#7
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unvented gas fire
andyv wrote:
I'm still undecided, but it's an interesting comment about gas cookers as these usually vent straight into the kitchen. Not everybody has an extractor. yes, but only for limited time. Running one all day is not smart. I wouldnt install an unvented fire myself. They arent as safe as vented, but more to the point youre breathing in the fumes day in day out. I've been to a few places with old ones installed and cant say I liked the atmosphere too much. They will also deposit a fair amount of damp of course. I think you could do better. NT |
#8
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unvented gas fire
OK I think I have a viable idea. See what you think.
The existing fire has a chimney which runs up the cavity wall into the loft. Here it runs in a concrete pipe and exhausts out through a vent in the apex of the roof. What if I was to fit an extractor fan into the piped section in the loft? I could then have the room downstairs turning over the air and sucking out the excess CO2 just as if it was going out of the window or a conventional vent in the wall. I'd have a grating on the wall hidden behind furniture. I don't fancy an extractor fan in the room itself unless anybody can point me to an ultra quiet one. Also it may even be possible to get a switch which operates when the gas is flowing so the fan is automatically turned on. |
#9
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unvented gas fire
andyv wrote:
OK I think I have a viable idea. See what you think. The existing fire has a chimney which runs up the cavity wall into the loft. Here it runs in a concrete pipe and exhausts out through a vent in the apex of the roof. What if I was to fit an extractor fan into the piped section in the loft? I could then have the room downstairs turning over the air and sucking out the excess CO2 just as if it was going out of the window or a conventional vent in the wall. I'd have a grating on the wall hidden behind furniture. I don't fancy an extractor fan in the room itself unless anybody can point me to an ultra quiet one. Also it may even be possible to get a switch which operates when the gas is flowing so the fan is automatically turned on. If you install a vent in the living room wall, and leave the existing flue open, you can do away with the extractor fan altogether as the air will naturally flow up the chimney (it will even without a vent, hold a lit match in front of it if you don't believe me!) The manufacturers insist on their safety as do British standards and gods knows what other governing bodies, but when push comes to shove, the waste products from that fire are going to end up in that room at some stage in whatever form and over a long period of time, I can't see how this is going to be benificial to either the room or it's occupants. You'll find that a permanent vented room as mentioned above will make it a lot more comfortable, and dryer too considering the water produced by burning gas. |
#10
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unvented gas fire
OK I just found a government report on this at
http://www.hse.gov.uk/research/rrpdf/rr023.pdf Basically what it says is that when they had several of these fires tested, they ended up with CO2 in excess of permitted occupational exposure levels. These were admittedly tested at extreme conditions but it doesn't fill me with much confidence.. |
#11
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unvented gas fire
andyv wrote:
OK I just found a government report on this at http://www.hse.gov.uk/research/rrpdf/rr023.pdf Basically what it says is that when they had several of these fires tested, they ended up with CO2 in excess of permitted occupational exposure levels. These were admittedly tested at extreme conditions but it doesn't fill me with much confidence.. CO2 isn't toxic. It's when there is no oxygen left in the room that the fire takes in the CO2 and produces CO - carbon monoxide. With good ventilation this can never happen, although breathing in CO2 isn't much fun, it won't kill you outright. As you say, the testing conditions would probably *never* occur in real life - how many rooms are completely sealed and air tight? A few vents, probably one in each side if it's possible for cross-flow ventilation, although not imperative would certainly make it more comfortable. |
#12
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unvented gas fire
On Mon, 10 Apr 2006 14:22:23 GMT, "Phil L"
wrote: |andyv wrote: | OK I just found a government report on this at | http://www.hse.gov.uk/research/rrpdf/rr023.pdf | | Basically what it says is that when they had several of these fires | tested, they ended up with CO2 in excess of permitted occupational | exposure levels. These were admittedly tested at extreme conditions | but it doesn't fill me with much confidence.. | |CO2 isn't toxic. Not strictly true. http://en.wikipedia.org/wiki/Carbon_dioxide When inhaled in high concentrations (about 5% by volume), it is toxic to humans and other animals. This is sometimes known as choke damp, an old mining industry term, and was the cause of death at Lake Nyos in Cameroon, where an upwelling of CO2-laden lake water in 1986 covered a wide area in a blanket of the gas, killing nearly 2000.. |It's when there is no oxygen left in the room that the fire takes in the CO2 |and produces CO - carbon monoxide. See above: -- Dave Fawthrop dave hyphenologist co uk Google Groups is IME the *worst* method of accessing usenet. GG subscribers would be well advised get a newsreader, say Agent, and a newsserver, say news.individual.net. These will allow them: to see only *new* posts, a killfile, and other goodies. |
#13
Posted to uk.d-i-y
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unvented gas fire
Dave Fawthrop wrote:
"Phil L" wrote: |andyv wrote: | OK I just found a government report on this at | http://www.hse.gov.uk/research/rrpdf/rr023.pdf | | Basically what it says is that when they had several of these fires | tested, they ended up with CO2 in excess of permitted occupational | exposure levels. These were admittedly tested at extreme conditions | but it doesn't fill me with much confidence.. | |CO2 isn't toxic. Not strictly true. http://en.wikipedia.org/wiki/Carbon_dioxide It is true, CO2 is non-toxic. To say it is toxic is like saying that water is toxic because you can drown in it. |It's when there is no oxygen left in the room that the fire takes in the CO2 |and produces CO - carbon monoxide. Shorely shome mishtake here. If there's no oxygen in the room, the fire will go out. CO2 doesn't burn. |
#14
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unvented gas fire
Chris Bacon wrote:
Dave Fawthrop wrote: "Phil L" wrote: andyv wrote: OK I just found a government report on this at http://www.hse.gov.uk/research/rrpdf/rr023.pdf Basically what it says is that when they had several of these fires tested, they ended up with CO2 in excess of permitted occupational exposure levels. These were admittedly tested at extreme conditions but it doesn't fill me with much confidence.. CO2 isn't toxic. Not strictly true. http://en.wikipedia.org/wiki/Carbon_dioxide It is true, CO2 is non-toxic. To say it is toxic is like saying that water is toxic because you can drown in it. Correct, carbon dioxide is in our lungs nearly all the time, given that we inhale oxygen and exhale carbon dioxide. It's when there is no oxygen left in the room that the fire takes in the CO2 and produces CO - carbon monoxide. Shorely shome mishtake here. If there's no oxygen in the room, the fire will go out. CO2 doesn't burn. There's always /some/ oxygen in the room, it's just that high concentrations of CO2 cause the hydrocarbons in the gas to not burn properly, when this occurs the gas produces CO instead of CO2....it doesn't actually *turn* CO2 into CO, but CO2 does cause the production of CO, given that it's presence is in place of oxygen. |
#15
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unvented gas fire
On Mon, 10 Apr 2006 16:48:46 +0100, Chris Bacon
wrote: |Dave Fawthrop wrote: | "Phil L" wrote: | |andyv wrote: | | OK I just found a government report on this at | | http://www.hse.gov.uk/research/rrpdf/rr023.pdf | | | | Basically what it says is that when they had several of these fires | | tested, they ended up with CO2 in excess of permitted occupational | | exposure levels. These were admittedly tested at extreme conditions | | but it doesn't fill me with much confidence.. | | | |CO2 isn't toxic. | | Not strictly true. | http://en.wikipedia.org/wiki/Carbon_dioxide | |It is true, CO2 is non-toxic. To say it is toxic is like saying |that water is toxic because you can drown in it. If you read what you snipped 5% CO2 is lethal which leaves about 15% oxygen http://en.wikipedia.org/wiki/Air If you took the trouble to read the rest of http://en.wikipedia.org/wiki/Carbon_dioxide and followed the internal links, you would find the reason in great detail. .. -- Dave Fawthrop dave hyphenologist co uk Google Groups is IME the *worst* method of accessing usenet. GG subscribers would be well advised get a newsreader, say Agent, and a newsserver, say news.individual.net. These will allow them: to see only *new* posts, a killfile, and other goodies. |
#16
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unvented gas fire
Dave Fawthrop wrote:
On Mon, 10 Apr 2006 14:22:23 GMT, "Phil L" wrote: |andyv wrote: | OK I just found a government report on this at | http://www.hse.gov.uk/research/rrpdf/rr023.pdf | | Basically what it says is that when they had several of these fires | tested, they ended up with CO2 in excess of permitted occupational | exposure levels. These were admittedly tested at extreme conditions | but it doesn't fill me with much confidence.. | |CO2 isn't toxic. Not strictly true. http://en.wikipedia.org/wiki/Carbon_dioxide When inhaled in high concentrations (about 5% by volume), it is toxic to humans and other animals. This is sometimes known as choke damp, an old mining industry term, and was the cause of death at Lake Nyos in Cameroon, where an upwelling of CO2-laden lake water in 1986 covered a wide area in a blanket of the gas, killing nearly 2000.. Next question is at what level does it have some effect on health. I dont know. NT |
#17
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unvented gas fire
Dave Fawthrop wrote:
Chris Bacon wrote: |Dave Fawthrop wrote: | "Phil L" wrote: | |andyv wrote: | | OK I just found a government report on this at | | http://www.hse.gov.uk/research/rrpdf/rr023.pdf | | | | Basically what it says is that when they had several of these fires | | tested, they ended up with CO2 in excess of permitted occupational | | exposure levels. These were admittedly tested at extreme conditions | | but it doesn't fill me with much confidence.. | | | |CO2 isn't toxic. | | Not strictly true. | http://en.wikipedia.org/wiki/Carbon_dioxide | |It is true, CO2 is non-toxic. To say it is toxic is like saying |that water is toxic because you can drown in it. If you read what you snipped 5% CO2 is lethal which leaves about 15% oxygen http://en.wikipedia.org/wiki/Air If you took the trouble to read the rest of http://en.wikipedia.org/wiki/Carbon_dioxide and followed the internal links, you would find the reason in great detail. . So water is toxic, too. Whatever you want. |
#18
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unvented gas fire
On Tue, 11 Apr 2006 10:15:25 +0100, Chris Bacon
wrote: |Dave Fawthrop wrote: | Chris Bacon wrote: | | |Dave Fawthrop wrote: | | "Phil L" wrote: | | |andyv wrote: | | | OK I just found a government report on this at | | | http://www.hse.gov.uk/research/rrpdf/rr023.pdf | | | | | | Basically what it says is that when they had several of these fires | | | tested, they ended up with CO2 in excess of permitted occupational | | | exposure levels. These were admittedly tested at extreme conditions | | | but it doesn't fill me with much confidence.. | | | | | |CO2 isn't toxic. | | | | Not strictly true. | | http://en.wikipedia.org/wiki/Carbon_dioxide | | | |It is true, CO2 is non-toxic. To say it is toxic is like saying | |that water is toxic because you can drown in it. | | If you read what you snipped 5% CO2 is lethal which leaves about 15% | oxygen http://en.wikipedia.org/wiki/Air | | If you took the trouble to read the rest of | http://en.wikipedia.org/wiki/Carbon_dioxide and followed the internal | links, you would find the reason in great detail. | . | |So water is toxic, too. In huge quantities taken by mouth, Yes. |Whatever you want. Not me Wikipedia, or Google will get you lots of other URLs saying the same things. -- Dave Fawthrop dave hyphenologist co uk Google Groups is IME the *worst* method of accessing usenet. GG subscribers would be well advised get a newsreader, say Agent, and a newsserver, say news.individual.net. These will allow them: to see only *new* posts, a killfile, and other goodies. |
#19
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unvented gas fire
Chris Bacon wrote: Dave Fawthrop wrote: Chris Bacon wrote: |Dave Fawthrop wrote: | "Phil L" wrote: | |andyv wrote: | | OK I just found a government report on this at | | http://www.hse.gov.uk/research/rrpdf/rr023.pdf | | | | Basically what it says is that when they had several of these fires | | tested, they ended up with CO2 in excess of permitted occupational | | exposure levels. These were admittedly tested at extreme conditions | | but it doesn't fill me with much confidence.. | | | |CO2 isn't toxic. | | Not strictly true. | http://en.wikipedia.org/wiki/Carbon_dioxide | |It is true, CO2 is non-toxic. To say it is toxic is like saying |that water is toxic because you can drown in it. If you read what you snipped 5% CO2 is lethal which leaves about 15% oxygen http://en.wikipedia.org/wiki/Air If you took the trouble to read the rest of http://en.wikipedia.org/wiki/Carbon_dioxide and followed the internal links, you would find the reason in great detail. . So water is toxic, too. Whatever you want. Not really. Trying to breath a mixture of 15% oxygen, 5% helium (or some other inert gas), and 80% nitrogen will be fine. Replace the 5% helium with 5% CO2, and you will be fine. Of course, CO2 is a lot less toxic than many gasses, but it isn't entirely non-toxic. |
#20
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unvented gas fire
Dave Fawthrop wrote:
Not me Wikipedia, or Google will get you lots of other URLs saying the same things. CO2 isn't toxic inthat it will kill you by poisoning, it may kill you via the non-presence of oxygen but it's not toxic like carbon monoxide, I think this is all getting pedantic now anyway, we breath carbon dioxide every day from our birth to our deaths, if it was poisonous we wouldn't live very long. Carbon monoxide is poisonous and worse still it has cumulative effects, meaning that levels of it can build up in the bloodstream for weeks, months or even years unnoticed until one day it reaches the point where it causes death. |
#21
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unvented gas fire
On Tue, 11 Apr 2006 16:22:54 GMT, "Phil L"
wrote: |Dave Fawthrop wrote: | | Not me Wikipedia, or Google will get you lots of other URLs saying | the same things. | |CO2 isn't toxic inthat it will kill you by poisoning, it may kill you via |the non-presence of oxygen but it's not toxic like carbon monoxide, I think |this is all getting pedantic now anyway, we breath carbon dioxide every day |from our birth to our deaths, if it was poisonous we wouldn't live very |long. Some people should learn to use Google, and read what they find http://en.wikipedia.org/wiki/Carbon_dioxide Carbon dioxide content in fresh air is approximately 0.04%, and in exhaled air approximately 4.5%. When inhaled in high concentrations (about 5% by volume), ***it is toxic to humans and other animals.*** This is sometimes known as choke damp, an old mining industry term, and was the cause of death at Lake Nyos in Cameroon, where an upwelling of CO2-laden lake water in 1986 covered a wide area in a blanket of the gas, killing nearly 2000. Hemoglobin, the main oxygen-carrying molecule in red blood cells, can carry both oxygen and carbon dioxide, although in quite different ways. The decreased binding to oxygen in the blood due to increased carbon dioxide levels is known as the Haldane Effect, and is important in the transport of carbon dioxide from the tissues to the lungs. Conversely, a rise in the partial pressure of CO2 or a lower pH will cause offloading of oxygen from hemoglobin. This is known as the Bohr Effect. -- Dave Fawthrop dave hyphenologist co uk Google Groups is IME the *worst* method of accessing usenet. GG subscribers would be well advised get a newsreader, say Agent, and a newsserver, say news.individual.net. These will allow them: to see only *new* posts, a killfile, and other goodies. |
#22
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unvented gas fire
Dave Fawthrop wrote:
"Phil L" wrote: |Dave Fawthrop wrote: | Not me Wikipedia, or Google will get you lots of other URLs saying | the same things. | |CO2 isn't toxic inthat it will kill you by poisoning, it may kill you via |the non-presence of oxygen but it's not toxic like carbon monoxide Some people should learn to use Google, and read what they find http://en.wikipedia.org/wiki/Carbon_dioxide Hell's bells. *Still* running wide. Try these: http://tinyurl.com/fmqzb http://www.woodlandsltd.com/acatalog...inkers_45.html |
#23
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unvented gas fire
Dave Fawthrop wrote:
On Tue, 11 Apr 2006 16:22:54 GMT, "Phil L" wrote: Dave Fawthrop wrote: Not me Wikipedia, or Google will get you lots of other URLs saying the same things. CO2 isn't toxic inthat it will kill you by poisoning, it may kill you via the non-presence of oxygen but it's not toxic like carbon monoxide, I think this is all getting pedantic now anyway, we breath carbon dioxide every day from our birth to our deaths, if it was poisonous we wouldn't live very long. Some people should learn to use Google, and read what they find http://en.wikipedia.org/wiki/Carbon_dioxide what part of 'this is all getting pedantic now' did you not grasp? - the Op doesn't live in a dissused mine in outer mongolia, he lives in a house, the CO2 levels cannot get that high under these circumstances otherwise how would anyone *ever* die of monoxide poisoning? I don't know why you are seeking glory with this, you are just making yourself look foolish....AFWIW, Wiki is written by anyone, I could go and edit any page right now to prove any point I like, primary schoolkids know that we breath CO2 every day and it's not toxic, if it was there wouldn't be any need for primary schools because we wouldn't be here. |
#24
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unvented gas fire
primary schoolkids know that we breath CO2 every day and it's not
toxic, if it was there wouldn't be any need for primary schools because we wouldn't be here. The problem is not pedanticism. The problem is that the statement "CO2 is not toxic" is false. It is toxic. It is not displacement of oxygen that causes this toxicity. It is only toxic in concentrations that are unlikely to occur in a domestic setting. You call being correct pedantic. However, others can't allow such a false statement to continue unchallenged. Christian. |
#25
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unvented gas fire
Christian McArdle wrote:
primary schoolkids know that we breath CO2 every day and it's not toxic, if it was there wouldn't be any need for primary schools because we wouldn't be here. The problem is not pedanticism. The problem is that the statement "CO2 is not toxic" is false. It is toxic. It is not displacement of oxygen that causes this toxicity. Toxic means it poisons you, so if we all have it around us all the time, how do we manage to live for 70 years? - why does it not kill us slowly like lead or other elements? It is only toxic in concentrations that are unlikely to occur in a domestic setting. Which is what we were talking about....and the pedantics started creeping in around here. You call being correct pedantic. However, others can't allow such a false statement to continue unchallenged. Because they're being pedantic...everything is toxic *given the right volumes and concentrations* - it was obvious to anyone with even half a degree of common sense that it was to this room, with the unvented gas fire inside it that I was referring, unless I'm expected to end each sentence with, "in the context of this room, with the unvented gas fire inside it" |
#26
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unvented gas fire
On Wed, 12 Apr 2006 16:38:35 +0000, Phil L wrote:
Christian McArdle wrote: primary schoolkids know that we breath CO2 every day and it's not toxic, if it was there wouldn't be any need for primary schools because we wouldn't be here. The problem is not pedanticism. The problem is that the statement "CO2 is not toxic" is false. It is toxic. It is not displacement of oxygen that causes this toxicity. Toxic means it poisons you, so if we all have it around us all the time, how do we manage to live for 70 years? - why does it not kill us slowly like lead or other elements? AIUI there are at least two aspect to toxicity. How much (or what concentration) will kill you in a given short time. How much can you be exposed to regularly and have no long term ill effects. I believe that CO2 needs something around 15% plus in air to kill you in hours. (IIRC the concentrations in Apollo 13 got over 10% before they managed to get the LiOH filters working.) Clearly exposure values of less than 0.5% are both unavoidable and inconsequential. I'm informed that 4000ppm of CO is fatal in minutes. The safe exposure limit is 50ppm. AIUI even water has a toxicity (IIRC something like 10 litres in less than 60minutes is fatal). -- Ed Sirett - Property maintainer and registered gas fitter. The FAQ for uk.diy is at http://www.diyfaq.org.uk Gas fitting FAQ http://www.makewrite.demon.co.uk/GasFitting.html Sealed CH FAQ http://www.makewrite.demon.co.uk/SealedCH.html Choosing a Boiler FAQ http://www.makewrite.demon.co.uk/BoilerChoice.html |
#27
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unvented gas fire
Ed Sirett wrote:
On Wed, 12 Apr 2006 16:38:35 +0000, Phil L wrote: Christian McArdle wrote: primary schoolkids know that we breath CO2 every day and it's not toxic, if it was there wouldn't be any need for primary schools because we wouldn't be here. The problem is not pedanticism. The problem is that the statement "CO2 is not toxic" is false. It is toxic. It is not displacement of oxygen that causes this toxicity. Toxic means it poisons you, so if we all have it around us all the time, how do we manage to live for 70 years? - why does it not kill us slowly like lead or other elements? AIUI there are at least two aspect to toxicity. How much (or what concentration) will kill you in a given short time. How much can you be exposed to regularly and have no long term ill effects. I believe that CO2 needs something around 15% plus in air to kill you in hours. (IIRC the concentrations in Apollo 13 got over 10% before they managed to get the LiOH filters working.) Clearly exposure values of less than 0.5% are both unavoidable and inconsequential. I'm informed that 4000ppm of CO is fatal in minutes. The safe exposure limit is 50ppm. AIUI even water has a toxicity (IIRC something like 10 litres in less than 60minutes is fatal). So there's no possibility of carbon dioxide killing people in a domestic house, with an unvented gas fire? - pretty much what I said. Even the tests on them have proven that it doesn't get anywehere close to the 'permitted levels' boundary. |
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