Would it be better to hold your breath after smelling the presence of it or quickly inhale and exhale to get rid of it in your system(body)?

EDIT: Changed from carbon monoxide to cigarette smoke.

  • $\begingroup$ Carbon monoxide is odorless, so you won't be smelling it unless it's mixed with something else. Exhaling won't remove it from your system because it binds to hemoglobin. $\endgroup$
    – C_Z_
    Jan 28, 2016 at 15:40

1 Answer 1


You don't smell carbon monoxide in cigarette smoke. It's odorless. (And not exactly the part of cigarette smoke I would be worried about.)

You smell the other components of cigarette smoke. Which are not odorless.

Holding your breath and getting out of the smoke seems the way to go. Even better would be exhaling, then holding your breath until you are clear.[1]

Carbon monoxide, as well as other components of cigarette smoke like nicotine, are very good at getting into your blood stream quickly. Plus, when at rest, we inhale / exhale at only a fraction of our lung capacity. By (deeply) inhaling (your alternative course of action), you would just get more of the smoke into your lungs than you already have.

[1]: The trick with holding your breath is of course that, if you run out of breath while still in the middle of the smoke, you can't help but inhaling deeply...

  • $\begingroup$ What is your response to the answer given by @CactusWoman above ? $\endgroup$
    – Viv
    Jan 28, 2016 at 16:18
  • $\begingroup$ @Viv: What do you think I should respond? CO is odorless, I said so myself. Exhaling won't remove any CO already in your blood, that's true as well. But exhaling will remove (most of) the smoke still in your lungs. Besides, the generic advice would be a) a single lungfull of cigarette smoke won't kill you, and b) don't go where there is cigarette smoke if you are so worried...?!? Or is there a different, unspoken question underneath all this? $\endgroup$
    – DevSolar
    Jan 28, 2016 at 16:30
  • $\begingroup$ I do fully agree with your answer that holding your breath is a good option. But the answer of @CactusWoman of the chemicals binding to hemoglobin made me more intrigued that your "better" option of exhaling would clearly not make much difference. So I was pondering if there an actual better way than your general advice/your answer. $\endgroup$
    – Viv
    Jan 28, 2016 at 16:42
  • 2
    $\begingroup$ @Viv: As I said, exhaling is for getting rid of what's in your lungs, not yet in your bloodstream. Not exhaling gives those molecules more time to cross over into your bloodstream, while at the same time lengthening the time until you need to inhale again, so it's a situational trade-off. Since you can't do an ad-hoc chemical scrubbing of your blood, exhaling while getting into fresh air is your best bet. $\endgroup$
    – DevSolar
    Jan 28, 2016 at 16:44

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