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Figure of FaTIMA model

The web-based tool Fate and Transport of Indoor Microbiological Aerosols (FaTIMA) allows for the determination of the indoor fate of microbiological aerosols associated with ventilation, filtration, deposition and inactivation mechanisms. FaTIMA provides a representation of a single, well-mixed zone that is served by a mechanical ventilation system and incorporates particle source and removal mechanisms. The simple mechanical ventilation system model allows specification of supply, return and fraction of outdoor air intake rate to include either a positive, negative or balanced ventilation system. Particle sources are provided to enable any combination of continuous, e.g., breathing related emissions, or intermittent, e.g., coughing-related, emissions. Particle removal mechanisms include filters within the ventilation system and deposition onto floors, walls and ceilings. Simulations can be run for a 24-h period, with the results including the time history of the airborne concentration and surface loading as well as integrated exposure that an occupant might experience.

NOTE: A flaw related to Particle Deactivation was corrected September 4, 2020. PRIOR TO this date, Particle Deactivation could be turned on or off, but the Particle Decay rate used in the simulation could not be changed from the default value.


The following spreadsheet can be used as a template into which CSV files generate by FaTIMA simulations can be imported. This is provided to simplify creating custom outputs graphics for FaTIMA. [fatima-csv-template.xlsx]


Created May 12, 2020, Updated May 26, 2021