Control of the outdoor air intake by the use of contaminant monitoring.

Reviews the possible indicators for monitoring the indoor air quality and controlling the outdoor air intake. The technical feasibility of the system is also discussed. At present CO2 seems to be the best and most reliable indicator for indoor air quality when occupancy load varies. In future, however, it is likely that measuring devices based on semiconductor technology and measuring devices for particles will be more reliable and inexpensive and so very suitable for controlling the air quality, because they can take into account both occupancy load and tobacco smoke. The air quality controlled ventilation system is easy to connect in almost all air conditioning systems,especially if recirculated air is used. In most buildings measuring from one point (exhaust air) will give an adequate result for controlling the air conditioning system.