You should absolutely seek medical treatment if you suspect you have been exposed to CO. I'm not trying to make light of that. My point is simply that CO is not actually as "clingy" as some in this thread are making it out to be.
I am a paramedic. We carry a portable CO meter on our "BLS bag" (the bag that gets brought in on the vast majority of calls), because more than once a "general illness" call has turned out to be CO poisoning.
Do you carry other equipment for personal protection like that (or the long version - what's in the bag!?)?
We are a combination fire/EMS agency, so I am also a firefighter, with all the gear that goes along with that.
As far as the bags go, we have three main bags:
-The "BLS" or "Airway" bag, which contains a lot of "basic" equipment (bandages, oxygen, some common meds, etc), as well as more advanced airway management equipment (laryngoscopes and endotracheal intubation tubes, etc).
-The "ALS" or "Med" bag, which contains all ~30 medications we carry, as well as IV fluids and all the necessary pointy things to get medications into people.
-The "Pediatric" or "Peds" bag, which contains most of the same stuff as the other two bags, just in smaller quantities, and sized for kids.
There are also a few other more specialized bags (the burn bag, the trauma bag, etc), and portable equipment (portable heart monitor[3], suction[4], etc)
[1]: Stock photo of a standard "class b" uniform: https://www.lansinguniform.com/wp-content/uploads/2014/05/Fi...
[2]: https://www.spservices.co.uk/images/products/pics/1407156050...
[3]: http://www.physio-control.com/ProductDetails.aspx?id=2147484...
[4]: https://www.boundtree.com/s-scort-iii-suction-unit-596400-ph...
Intuitively most people would think that just stopping to breathe CO is sufficient and breathing fresh air would displace it as quickly as with other common gasses (i.e. you may cough for a bit but recover in minutes) but the point is that CO is clingy.
EDIT: Elsewhere you agree with the assessment that the half-life under "fresh air" is somewhere around 4 hours, so I think you would agree that "just breathe fresh air for a bit" (implying minutes, maybe an hour) isn't a satisfactory treatment in serious cases.