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    Introduction to Diesel Exhaust: What Is Carbon Monoxide?

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    What is carbon monoxide? How does it kill? 

    Carbon monoxide is a gas that cannot be seen, tasted, or smelled. It is a byproduct of the incomplete burning of gasoline, wood, coal, oil, propane, or any other substance containing carbon.

    When carbon monoxide is inhaled, it attaches to hemoglobin, the protein molecule in red blood cells that carries oxygen to our brain and vital organs. Carbon monoxide binds over 200 times more aggressively to hemoglobin than does oxygen. As more and more hemoglobin is taken over by the carbon monoxide, less and less is available for oxygen. At a certain point, even if there is still oxygen in the air, the person suffocates.

    Low exposure to carbon monoxide causes headaches, dizziness, drowsiness, and nausea. Higher exposure leads to convulsions, coma, and death.[1]

    Carbon monoxide can be lethal to human beings when it exceeds 0.1 percent (1/10 of one percent) of the atmosphere. This means that 4,000 parts of carbon monoxide in 1,000,000 parts of atmosphere can be fatal. The higher the amount of carbon monoxide in the atmosphere the faster death occurs.[2]

    What is a diesel engine? How is it different from a gasoline engine?

    Both diesel and gasoline engines convert fuel into energy through a series of small combustions. The major difference between diesel and gasoline engines is the way these combustions happen. In a gasoline engine, the fuel is mixed with air in the carburetor. This fuel-air mix is then compressed by pistons and ignited by sparks from spark plugs. In a diesel engine the air is compressed first and then the fuel is injected. Because air heats up when it is compressed, the fuel ignites without the need for a spark. Diesel engines do not need carburetors and they use a heavier, more oily, gas. The diesel combustion process is more efficient that the gasoline combustion process. When the diesel engine is properly tuned, it produces less toxic exhaust and gets better gas mileage than a gasoline engine.

    Gasoline engine exhaust contains between 7 percent and 12 percent carbon monoxide, which is deadly to human beings. It is more deadly because the fuel and the air combine in the carburetor first and then create the spark for the combustion. This process does not burn all the fuel efficiently. The fuel that is not fully burned comes out in the exhaust in the form of toxic chemicals.

    On the other hand, a properly tuned diesel engine produces exhaust that contains about 1 percent carbon monoxide. This is the case because the fuel is burned much more efficiently, especially when the engine is idling. That is why truck drivers can leave their trucks on all night without fear and why diesel-powered vehicles and equipment are favored in mining or enclosed situations.


    [1] “Carbon monoxide poisoning” at http://en.wikipedia.org/wiki/Carbon_monoxide_poisoning.

    [2] Y. Henderson and H.W. Haggard, Noxious Gases (Reinhold Publishing, 1943), p.168 (Table 2) as cited by Friedrich Berg, “Diesel Gas Chambers: Ideal for Torture—Absurd for Murder, Part 1 at http://www.nazigassings.com/dieselgaschambera.html.