To prevent outside air from being drawn from the end of the collection pipe a water filled trap should be installed in the pipe beyond the point where the fan is attached.
Radon exhaust fan installation.
Another way to define this is any where outside the conditioned air space of the heating and air conditioning system.
Fans placed in attics garages and outside locations will keep you safe.
Manufacturers can accurately predict how much cfm an inline fan will move in these ducts.
However with radon fans you re at the mercy of soil conditions sub slab fill suction pit sizing and much more.
In the hvac world fans are always placed on a specified duct size 4 10.
Radon can be pulled from the soil beneath a house by attaching an exhaust fan to the collection pipe or to the sealed sump see page 9.
So how do you mitigate the expense as well as the radon.
All radon mitigation installation standards require that the radon fan be located outside the living space of the home.
Radon mitigation standards require that the fan to be placed outside of the living space of the home.
Radon mitigation system installation can be expensive and if you have radon you may feel like you cannot avoid that expense.
The location of the radon fan.
Perform a diy radon mitigation installation.
14 3 2 radon vent fans shall be sized to provide the pressure difference and air flow characteristics necessary to achieve the radon reduction.
The reasoning for this is that if a leak was to occur above the fan your house could have a really high radon level.
Get a final radon reading before you seal the sump cover.
14 3 radon vent fan installation requirements 14 3 1 vent fans used in radon mitigation systems shall be designed or otherwise sealed to reduce the potential for leakage of soil gas from the fan housing.
Reset your radon detector then wait 48 hours and check your reading again.
If all goes well you ll see a drastic reduction in radon.
After all the work is done the house will be re tested for radon.
You certainly should not go without a mitigation system over the long term if you know your home has high radon levels.
So garages attics and on the outside of the house are the only acceptable locations for fan placement.