Pressure, atmospheric ventilation effects

Installation of a radon sump system equipped with a fan is suggested as the most effective and best choice for high levels of radon existance [29]. For this, a sump which is a small empty space about the volume of a bucket is dug imder the solid floor and a pipe is routed from it to the outside air. The sump and the fan connected at the exit of the pipe to suck air, both help to alter the air pressure below the floor and to pass and to release it harmlessly into the atmosphere. There are also applications where the fan is replaced by a blowing system to facilitate the removal of the remaining of radon in the soil. It is also possible to increase the circulation of air beneath the floor (improved ventilation under suspended timber floors with or without a fan via an air-brick) or at loft level or even by using positive house ventilation as a whole ( positive pressurisation is most effective if house is very air-tight). 

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