Dry ice in a rotomolded cooler: yes, but don't seal it

Dry ice in a rotomolded cooler will absolutely keep food frozen for a week — those thick walls are exactly what dry ice needs. But you have to handle it smarter than you would with regular ice.

The big one: do not seal the cooler. Dry ice sublimates into CO2 gas, and if a rotomolded cooler is fully latched, pressure builds up until something gives. That something is usually the lid or the latch, and it happens with a bang. Crack the lid a few inches or leave the drain plug open. If you’re putting it in a car, crack a window too — CO2 pooling in a sealed cabin is a real asphyxiation risk, not a theoretical one.

Don’t let dry ice touch the cooler walls directly. It’s cold enough to crack the plastic on some models, and it will frostburn whatever food it touches. Lay down cardboard or a towel as a barrier, then put the dry ice on top of your frozen food. Keep it in a block, not pellets, so it lasts. And handle it with insulated gloves — bare skin contact gives you freezer burn in seconds, not minutes.

A 10-pound block in a good rotomolded cooler will keep a full load frozen for a week, easy, as long as you’re not opening it every hour. Thawed stuff that touches the dry ice will freeze solid again, which sounds convenient