Translations:AY Honors/Wilderness Living/Answer Key/43/en

Finally, cut three or four vent holes in the ceiling. This will allow stale air to escape. The vent holes need only be 5 cm in diameter, but they must be made, or you will be re-breathing the C0₂ you exhaled previously. If you plan to light a candle inside, the vents are even more important, as they will allow carbon monoxide to escape.