Q: Carbon monoxide question

Thanks for your interesting scientific question. Actually, sort of unexpectedly, as the research turned out the principal hazard to the public (i.e., you) from CO (as measured by both mortality and morbidity statistics) has turned out to be the chronic exposure to CO that tens of millions of people experience, not the acute incidents, causing death, that you read about in the newspaper or hear on the news.

That is, a principle scientific finding has that sub-lethal, long term (chronic) exposure to CO, in polluted cities (or that you are contemplating in the garage) is causes permanent, or at least long term, damage to the cardiovascular system as well as the tissues in certain organs. You can readily learn about this "chronic" versus "acute" distinction, and the death toll attributable to each category of exposure, on the Internet.

With regard to your specific question, yes, you could definitely die from acute exposure over 2 hours in a closed in garage (and probably a lot less time than that if the motor is running continuously). Ideally, the acceptable level of exposure to this deadly molecule is close to zero PPM. Consequently, you would be unwise to knowingly occupy a "closed in" or confined space where you are sure the gas is being produced

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