We pointed out the noise factor and provided ideas on nozzle positioning.
Taking into consideration the requirement that the mist be undetectable by the human senses, the droplet size should be maintained within tens of microns. Nozzles that spray two mixed fluids (including air) can produce such droplets easily. However, if many such spray nozzles were to be installed indoors, the noise resulting from the propellant (air) cutting into the atmosphere may be a problem. You would be better advised to make use of a burner-type spray nozzle that sprays a single fluid of 2.0-3.0 L/H at 0.5-0.7 MPa. To fully circulate the mist through the rooms so that it disinfects efficiently, you should install such spray nozzles at the intakes of the air conditioning system, and at places in which the air currents within the building will work to your advantage.