This approach is described as a "passive" system because once initial conditions are set inside the flask, a continuing presence of helium and good insulation is all that is required to maintain those conditions.

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Ms. TRAIL ZEA: The roof is down to the plywood and it caved in--the roof is caved in on the baby's room, so the baby's crib is all full of roof and insulation.

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There were no inside-out insulation abrasions and no all-cause abrasions.

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