A Radon Soil Gas Control System is a barrier protection measure designed to control the natural movement of radon soil gas in the ground under a building.
Best Practice - New Buildings
Inside buildings the air pressure tends to be lower than pressure levels outside. This is due to a combination of wind and temperature differences. The result is that radon soil gas and air are drawn into buildings through the many small gaps and cracks formed during, and after, construction, e.g. in solid floors and walls at ground level, through construction joints and around service pipes.
Radon, Air and Moisture is excluded from buildings using passive protection measures. Radon can also be removed using active protection.
Best Practice 1: During Construction: You should provide for a passive protection measure by installing a system that separates the interior spaces of a building from the underlying soil.

How to achieve this objective.
Best Practice 2: During Construction: You should make provision for an active protection measure by installing radon sump and connecting pipework.

How to achieve this objective
Best Practice 3: Post Construction: You should have the new building tested for radon gas.

How to achieve this objective
Best Practice 4: What you do if you need to activate the radon soil gas barrier protection system.

How to achieve this objective
Best Practice 5: You should ensure that all habitable rooms are adequately ventilated.
Best Practice 6: Re-test radon soil gas levels after the barrier system is activated and monitor the fan in use.
Existing Buildings
Should the installation of an activated radon soil gas control system (with a resulting alteration to sub-floor pressure) ever be considered in an existing building, it must always be established, prior to the commencement of any works, that there is sufficient separation between the sub-floor construction and interior spaces and superstructure construction cavities. Depending on age, an existing building may or may not have a ground floor Radon barrier membrane, or a damp resisting membrane.