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How long to remain in shelter-in place room

DHS recommends that individuals allow ten square feet of floor space per person in order to provide sufficient air to prevent carbon dioxide build up for up to hours assuming normal breathing rate while resting. Many chemical releases would be diluted within few hours, so the direction to shelter-in-place would likely be made for short time period while chemical cloud dissipates.

Last Updated: 08/28/2019

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