Aerosols persistence

Because of the complexity of the actual structures, the emphasis in modeling has been on obtaining an average representation, and the variability among individuals tends to be neglected. There are two experimental studies of variability of airway dimensions in living humans as revealed by aerosol-deposition studies. Lapp et al. assessed the size of alveolar spaces in terms of half-life of aerosol persistence during breath-... 

Palmes ED, Wang CS, Goldring RM, Altshuler B. Effect of depth of inhalation on aerosol persistence during breath holding. J Appl Physiol 1973, 34, 356-360. 

Immediately isolate an area around any liquid or solid contamination for at least 700 feet in all directions. If possible, identify the agent and develop a downwind hazard diagram (see Table 3.2). Adjust the initial isolation distance as appropriate. Based on the type of release, amount of material aerosolized, persistence of the agent and local conditions (e.g., weather, population density, time of day), shelter-in-place until the initial cloud passes may be the most appropriate course of action since timely evacuation of the threatened downwind population may not be possible. Depending on the persistence of the agent and the potential for condensation of agent from the cloud, evacuation of the threatened population after passage of the initial cloud may be appropriate. 

Immediately isolate an area around any liquid or solid contamination for at least 400 feet in all directions. If possible, identify the agent and develop a downwind hazard diagram (see Table 3.2). Adjust the initial isolation distance as appropriate. Based on the type of release, amount of material aerosolized, persistence of the agent and local conditions (e.g., weather. 

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