Determine the ventilation rate, outdoor-air rate, and the re-circulated-air rates for a hotel lobby if smoking is permitted. An air cleaning device of 30% efficiency for removal of tobacco smoke is available. The outdoor-air requirement for ventilation is shown below. Function Outdoor air required per person(litre/sec) Estimated occupancy/100m floor space. Rooms Club arena Lobby 7 60 30 smoking 10 17.5 7.5 Non smoking 2.5 3.5 2.5