The draught rate determines the percentage of affected people by an airflow
caused due to room ventilation or buoyancy effects (cold windows). The draught
rate calculation is valid for room temperatures between 20 and 26 degrees
Celsius and airspeed less than 0.5 m/s. This quantity is used widely for
quantifying offices, auditoriums, or similar rooms in which persons are working.
Patch contributed by Tobias Holzmann
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