Social Impacts of Disaster - FEMA

As Wilson (1987) emphasizes, an infiltration rate of 1.0 ACH does not imply that all the clean air will be gone in one hour. Rather, the proportion of contaminated air gradually rises until at the end of 1.0 tB hours, 63% of the original air has been replaced by contaminated air, while 95% of the original air has been replaced by the end of 3.0 ... ................
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