carbon monoxide

[doc henderson]

was about to comment in @Old Greenhorn in the Topic: Stupid idea? Using attic heat? .  decided to make a separate conversation, since winter is the time carbon monoxide poisoning is most common.  The world is made up of gasses, and nature designed a way to let animals walk around and get gas exchange (out of the water)  We have cellular energy processes that require electron transport to create energy in the cell.  the mitochondria is the "powerhouse of the cell"  and to process sugar into energy, we need to have a terminal electron receptor.  in our world and chemistry this is Oxygen.  O2.  We use O2 to help extract energy from sugar and create water H2O and carbon dioxide CO2.   In the process we turn ADP into ATP and this is the energy currency of the cell.  carbon monoxide is what happens when carbon containing energy sources are not fully or efficiently burned.  It occurs in nature, and is made by nearly all combustion processes.  the newer more efficient boilers are so efficient, that the flues are pvc pipe, and if the pipe breaks, the level of CO is so low that is rarely causes a problem.  Our CO level in humans is 0 to 5%, in smokers it is normal to be up to 10%.  We have all seen the pulse ox machines that read our "oxygen" levels and it is normal to be 97%.  anything over about 88 to 90 is ok.  but the machine really reads the % of saturated Hemoglobin.  Hg.  The problem is that CO binds 200 times more tightly than O2 to hemoglobin.  this is why we call is an asphyxiation.  The antidote is high concentration O2 to overwhelm the chemistry by a concentration gradient.  Yu Hg may be 97% saturated as it leaves the lungs, but when it returns it is about 75%.  so it cannot fully unload all the O2.  If you have Hg that is 50% bound by CO and 50% bound by O2, the pulse ox reads 100%.  50% CO is lethal.  gas engines, or heaters that should be vented outside are the most common problems.  be safe!