Be sure not to confuse CO2
(carbon dioxide) with CO (carbon monoxide). Seems to be happening in several threads lately.
is a byproduct of human respiration as well as combustion and occurs naturally in the atmosphere. It is only dangerous in high concentrations as it displaces the oxygen
. As you say, keeping a window or vent open slightly is enough to keep it from building up excessively when cooking or even sleeping (especially with four of us in such a tiny space).
CO is a highly toxic byproduct of combustion sometimes formed in small quantities along with the normal CO2
O. Since it can be fatal in low concentrations before you are even aware of its presence, a working carbon monoxide detector is a critical safety device, both in the trailer and at home.