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Buddy Portable Catalytic Heater
On 12 Nov 2005 19:18:03 -0600, Dave wrote:
On Sun, 13 Nov 2005 00:57:33 GMT, Brian Whatcott said: ? Have you tried a paper bag over the head for CO2 enrichment? Doesn't answer the question. The paper bag over the head will increase the CO2 as a percentage of the mixture and reduce the percentage of O2, rather than leaving both constant.. The question I thought I was addressing is the safety of room exhausted heaters. This was to note that we don't just flake out and die, but tend to get a respiratory alert when the CO2 proportion gets high. Presumably why the things are allowed under most codes. Brian Whatcott Altus OK |
Buddy Portable Catalytic Heater
Dave wrote:
On Sat, 12 Nov 2005 22:42:24 GMT, Rosalie B. said: Actually an excess of CO2 can be a problem, it's just a problem at a higher concentration than CO is. The IDLH (immediately dangerous to life and health) limit for CO2 is 40,000 ppm whereas CO has an IDLH of 1200 ppm CO2 is regarded as a simple asphixiant, just like an excess of nitrogen or any other inert gas. You're exhibiting the same confusion. The difference between CO2 and CO is that CO2 may displace oxygen in the air, reducing the oxygen concentration below the level required to sustain life. It is, as you say, an asphixiant, but is not a poison. I suspect that the assumption behind the figures you The figures I quoted came from NIOSH, and the ppm (parts per million) are in air. NIOSH's Immediately Dangerous to Life and Health mean just that -- 40,000 ppm would kill you even though that would be only ..04% if I've got my decimals correct. You could still have enough oxygen (20%) in air to sustain life even with that amount of carbon dioxide in the air, but you would have symptoms including headache, dizziness, restlessness, paresthesia; dyspnea (breathing difficulty); sweating, malaise (vague feeling of discomfort); increased heart rate, cardiac output, blood pressure; coma; asphyxia; convulsions; or frostbite (if it was liquid, or dry ice) quote is that the remaining gas other than the CO2 is air. Unless I'm mistaken, you could live for an indefinite period breathing a mixture of 80% CO2 and 20% O2, just as you could live for an indefinite period breathing 80% helium and 20% O2. CO2, being inert, doesn't combine with anything in your blood's hemoglobin to block oxygen transport. No you couldn't live for any period of time with that amount of CO2 in the air like you could with helium which is really an inert gas. It is a simple asphyxiant but you don't have to have 81% of it in the air to die from it. It screws up your brain's notice to the body to breathe. Any gas that displaces oxygen down below about 19% will asphyxiate you whether it is poisonous or not. For instance Freon or an excess of nitrogen will both do it. CO on the other hand, is a true poison in that even if there is enough oxygen in the air to sustain life, the CO would prevent the blood from transporting the oxygen from the lungs to the brain and other organs. Yes you can be poisoned by CO even in the presence of plenty of O2. Of course it is also true that any burning or other oxidation produces CO2, but when there's insufficient O2 to form CO2, the CO will be formed instead. Other poisonous gases are chlorine, and of course cyanide. Matter of fact, O2 at high pressure and concentration is poisonous, leading to convulsions and ultimately death.. Most of the time what happens with O2 in excess of 23.5% is that there is so much danger of fire (asphalt becomes combustible in pure oxygen). The context I'm familiar with is diving, where part of the decompression process when you've been breathing helium oxygen mixture involves switching to pure O2 at the 60 ft. stop to reduce the partial pressure of the helium and flush it out of your system. Can't switch at lower depths because of the risk of O2 poisoning at higher pressures. OK - I was thinking of industrial uses of pure oxygen. Big tanks of pure oxygen like they have in hospitals or places where they do a lot of oxyacetylene welding can cause fire problems. grandma Rosalie |
Buddy Portable Catalytic Heater
Would you mind explaining the occasion of your CO2 poisoning? I suspect that
you meant CO poisoning, just want to clarify or learn something new. BF "ahoy" wrote in message ... The mining people used to say men could work best at 23% oxygen, could work poorly but still keep going at 15% and at 13% they were taken out. When I was on oxygen after C02 poisoning they had someone in attendance to remove the mask every so often as the autonomic (?) brain stem part of your system that makes breathing automatic relies on the percentages being in proportion. Carbon dioxide level is the meter that tells you it's time to take another breath it seems. On Sun, 13 Nov 2005 01:54:33 GMT, Rosalie B. wrote: Dave wrote: On Sat, 12 Nov 2005 22:42:24 GMT, Rosalie B. said: Actually an excess of CO2 can be a problem, it's just a problem at a higher concentration than CO is. The IDLH (immediately dangerous to life and health) limit for CO2 is 40,000 ppm whereas CO has an IDLH of 1200 ppm CO2 is regarded as a simple asphixiant, just like an excess of nitrogen or any other inert gas. You're exhibiting the same confusion. The difference between CO2 and CO is that CO2 may displace oxygen in the air, reducing the oxygen concentration below the level required to sustain life. It is, as you say, an asphixiant, but is not a poison. I suspect that the assumption behind the figures you The figures I quoted came from NIOSH, and the ppm (parts per million) are in air. NIOSH's Immediately Dangerous to Life and Health mean just that -- 40,000 ppm would kill you even though that would be only .04% if I've got my decimals correct. You could still have enough oxygen (20%) in air to sustain life even with that amount of carbon dioxide in the air, but you would have symptoms including headache, dizziness, restlessness, paresthesia; dyspnea (breathing difficulty); sweating, malaise (vague feeling of discomfort); increased heart rate, cardiac output, blood pressure; coma; asphyxia; convulsions; or frostbite (if it was liquid, or dry ice) quote is that the remaining gas other than the CO2 is air. Unless I'm mistaken, you could live for an indefinite period breathing a mixture of 80% CO2 and 20% O2, just as you could live for an indefinite period breathing 80% helium and 20% O2. CO2, being inert, doesn't combine with anything in your blood's hemoglobin to block oxygen transport. No you couldn't live for any period of time with that amount of CO2 in the air like you could with helium which is really an inert gas. It is a simple asphyxiant but you don't have to have 81% of it in the air to die from it. It screws up your brain's notice to the body to breathe. Any gas that displaces oxygen down below about 19% will asphyxiate you whether it is poisonous or not. For instance Freon or an excess of nitrogen will both do it. CO on the other hand, is a true poison in that even if there is enough oxygen in the air to sustain life, the CO would prevent the blood from transporting the oxygen from the lungs to the brain and other organs. Yes you can be poisoned by CO even in the presence of plenty of O2. Of course it is also true that any burning or other oxidation produces CO2, but when there's insufficient O2 to form CO2, the CO will be formed instead. Other poisonous gases are chlorine, and of course cyanide. Matter of fact, O2 at high pressure and concentration is poisonous, leading to convulsions and ultimately death.. Most of the time what happens with O2 in excess of 23.5% is that there is so much danger of fire (asphalt becomes combustible in pure oxygen). The context I'm familiar with is diving, where part of the decompression process when you've been breathing helium oxygen mixture involves switching to pure O2 at the 60 ft. stop to reduce the partial pressure of the helium and flush it out of your system. Can't switch at lower depths because of the risk of O2 poisoning at higher pressures. OK - I was thinking of industrial uses of pure oxygen. Big tanks of pure oxygen like they have in hospitals or places where they do a lot of oxyacetylene welding can cause fire problems. grandma Rosalie |
Buddy Portable Catalytic Heater
"BF" wrote:
Would you mind explaining the occasion of your CO2 poisoning? I suspect that you meant CO poisoning, just want to clarify or learn something new. BF "ahoy" wrote in message .. . The mining people used to say men could work best at 23% oxygen, could work poorly but still keep going at 15% and at 13% they were taken out. 23% oxygen is too much. Normally it is 20% or 21% at the most. 19% is marginal. Oxygen content should be less than 23% but maintained at levels greater than 18%. 15% is WAY too little. Candles go out at about 16 percent; 15 percent is the approximate beginning level of dangerous hypoxia (lack of adequate body oxygen) with increasing, unrecognized grogginess. At 12 or 13 percent the situation is critical, and in 7 to 8 percent oxygen death is rapid. When I was on oxygen after C02 poisoning they had someone in attendance to remove the mask every so often as the autonomic (?) brain stem part of your system that makes breathing automatic relies on the percentages being in proportion. Carbon dioxide level is the meter that tells you it's time to take another breath it seems. Carbon dioxide in outdoor air averages about 400 mg/liter or parts per million. Carbon dioxide toxicity symptoms apparently appear at around 15,000 parts per million or 1.5% and above. OSHA has a Threshold Limit Value-Time Weighted Average (TLV-TWA), which is the time-weighted average concentration for a normal 8-hour workday and 40-hour workweek, to which nearly all workers may be repeatedly exposed, day after day, without adverse effect. The TLV-TWA for carbon dioxide is 5,000 parts per million (.5% or half a percent.) Carbon Dioxide (CO2) is the body's regulator of the breathing function. Any increase above the normal levels will cause accelerated breathing and heart rate. A concentration of 10% can cause respiratory paralysis and death within a few minutes. On Sun, 13 Nov 2005 01:54:33 GMT, Rosalie B. wrote: Dave wrote: On Sat, 12 Nov 2005 22:42:24 GMT, Rosalie B. said: Actually an excess of CO2 can be a problem, it's just a problem at a higher concentration than CO is. The IDLH (immediately dangerous to life and health) limit for CO2 is 40,000 ppm whereas CO has an IDLH of 1200 ppm CO2 is regarded as a simple asphixiant, just like an excess of nitrogen or any other inert gas. You're exhibiting the same confusion. The difference between CO2 and CO is that CO2 may displace oxygen in the air, reducing the oxygen concentration below the level required to sustain life. It is, as you say, an asphixiant, but is not a poison. I suspect that the assumption behind the figures you The figures I quoted came from NIOSH, and the ppm (parts per million) are in air. NIOSH's Immediately Dangerous to Life and Health mean just that -- 40,000 ppm would kill you even though that would be only .04% if I've got my decimals correct. You could still have enough oxygen (20%) in air to sustain life even with that amount of carbon dioxide in the air, but you would have symptoms including headache, dizziness, restlessness, paresthesia; dyspnea (breathing difficulty); sweating, malaise (vague feeling of discomfort); increased heart rate, cardiac output, blood pressure; coma; asphyxia; convulsions; or frostbite (if it was liquid, or dry ice) quote is that the remaining gas other than the CO2 is air. Unless I'm mistaken, you could live for an indefinite period breathing a mixture of 80% CO2 and 20% O2, just as you could live for an indefinite period breathing 80% helium and 20% O2. CO2, being inert, doesn't combine with anything in your blood's hemoglobin to block oxygen transport. No you couldn't live for any period of time with that amount of CO2 in the air like you could with helium which is really an inert gas. It is a simple asphyxiant but you don't have to have 81% of it in the air to die from it. It screws up your brain's notice to the body to breathe. Any gas that displaces oxygen down below about 19% will asphyxiate you whether it is poisonous or not. For instance Freon or an excess of nitrogen will both do it. CO on the other hand, is a true poison in that even if there is enough oxygen in the air to sustain life, the CO would prevent the blood from transporting the oxygen from the lungs to the brain and other organs. Yes you can be poisoned by CO even in the presence of plenty of O2. Of course it is also true that any burning or other oxidation produces CO2, but when there's insufficient O2 to form CO2, the CO will be formed instead. Other poisonous gases are chlorine, and of course cyanide. Matter of fact, O2 at high pressure and concentration is poisonous, leading to convulsions and ultimately death.. Most of the time what happens with O2 in excess of 23.5% is that there is so much danger of fire (asphalt becomes combustible in pure oxygen). The context I'm familiar with is diving, where part of the decompression process when you've been breathing helium oxygen mixture involves switching to pure O2 at the 60 ft. stop to reduce the partial pressure of the helium and flush it out of your system. Can't switch at lower depths because of the risk of O2 poisoning at higher pressures. OK - I was thinking of industrial uses of pure oxygen. Big tanks of pure oxygen like they have in hospitals or places where they do a lot of oxyacetylene welding can cause fire problems. grandma Rosalie grandma Rosalie |
Buddy Portable Catalytic Heater
"BF" wrote in
: Would you mind explaining the occasion of your CO2 poisoning? I suspect that you meant CO poisoning, just want to clarify or learn something new. BF CO2 is just as poisoning as CO. "We breathe out CO2 so it must be ok", they'll retort if you mention it. We breathe out a little CO2, not the output of a catalytic heater or CO2 extinguisher. I've seen Navy sailors with CO2 extinguishers overcome fighting a grease fire in the galley. The fire went out about the same time as the sailors....from CO2 and lack of oxygen. Please don't run UNVENTED heaters of any fuel inside the boat....Please? -- Larry |
Buddy Portable Catalytic Heater
Dave wrote:
On Sun, 13 Nov 2005 01:54:33 GMT, Rosalie B. said: Any gas that displaces oxygen down below about 19% will asphyxiate you whether it is poisonous or not. For instance Freon or an excess of nitrogen will both do it. No doubt about that. I was simply addressing the characterization of CO2 as a "poison." Anything in the world is a poison in the wrong quantities. Even water. So it is really immaterial whether CO2 is a poison or if it just asphyxiates you by displacing oxygen. In the case of CO, that really will severely impact your health at much lower levels than CO2, so I suppose one could call it a poison. Your 19% figure, by the way, is based on breathing at atmospheric pressure. When I was diving helium we would go below that level, with the percentage depending on the depth. Are you diving with a portable catalytic space heater? grandma Rosalie |
Buddy Portable Catalytic Heater
On Sun, 13 Nov 2005 01:54:33 GMT, Rosalie B.
wrote: ///NIOSH's Immediately Dangerous to Life and Health mean just that -- 40,000 ppm would kill you even though that would be only .04% if I've got my decimals correct. You could still have enough oxygen (20%) in air to sustain life /// grandma Rosalie Think of proportions this way: 40 thousand parts per million - is like 40 parts per thousand - is like 4 parts per hundred or 4% Brian Whatcott Altus OK |
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