Translations:Adventist Youth Honors Answer Book/Recreation/Wilderness Living/43/en
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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.
