A radon fan pulls from below the slab to reduce the entry force into the building.
In active sub-slab depressurization, a fan connected to suction points lowers pressure beneath the floor and discharges soil gas outdoors. Soil permeability and the connected collection network determine how far the pressure field reaches.
Follow the airflow through the equipment.
Entry pressure
Small pressure differences can draw soil gas through cracks and penetrations into a building.
Suction point
A pipe connects the aggregate or soil beneath the slab to the active system.
Pressure field
The fan lowers pressure around connected sub-slab spaces, subject to soil and slab resistance.
Outdoor discharge
Soil gas travels through a sealed exhaust route to an approved outdoor termination.
What the fan is responsible for
- Maintain the required negative pressure field across the connected sub-slab area.
- Operate continuously against the actual soil, suction-point and pipe resistance.
- Support monitoring and a safe response when airflow or fan operation is lost.
Why the route matters
- A single suction point may not communicate through a divided or low-permeability sub-slab area.
- Leaks, water or condensate can change the pressure path and fan duty.
- An unsafe discharge or fan location can create a new exposure or service problem.
Define these inputs before choosing a fan
A LONGWELL route to evaluate: inline radon-fan page family candidate
A current LONGWELL official inline-fan page is associated with radon service, but its title and body conflict on model identity, ingress protection and materials. Use it as an application association only. Before selection, require a current consistent datasheet and fan curve, continuous-duty evidence, installed airflow and suction, ingress and leakage review, condensate handling, alarm strategy and local mitigation approval.
Verify the complete equipment, not the fan in isolation
Bring the diagnostic pressure-field and pipe-network results.
Share the measured suction points, airflow, pressure, environment and approval requirements so LONGWELL can determine whether a suitable configuration is available.