A booster fan is a fan that helps the main ventilation fan by increasing airflow in difficult sections of the system. Instead of replacing the main fan, it works in series with it, adding extra pressure in a specific branch or length of duct. This allows air to travel through long, steep or high-resistance paths that the main fan alone would struggle to ventilate effectively.
In underground mines, a booster fan is installed in a main airway or district entry to push or pull more air through deep levels, remote stopes or long declines. It takes the airflow supplied by the surface main fan, raises its pressure and sends it further into the mine. By doing this, the booster fan helps ensure that each production area receives enough fresh air to dilute gases, diesel exhaust, blasting fumes and heat, even as the mine expands farther from the shafts.
In industrial plants and duct systems, a smaller booster fan may be installed in a long or heavily loaded duct where airflow has dropped below design values. For example, a duct booster fan can help deliver more air to a remote room, a process hood at the end of a long run or a branch with additional filters and dampers. By adding pressure at that location, the booster fan restores airflow without requiring a complete redesign of the central air-handling unit.
In both mining and industrial applications, a booster fan also allows operators to optimise energy use. Instead of oversizing the main fan to handle the worst-case branch, they can size the main fan for the overall network and use one or more booster fans where extra pressure is truly needed. This targeted approach often reduces total installed power and can make it easier to adjust air distribution as the mine layout or plant processes change.
However, because a booster fan alters the pressure distribution in the system, it must be carefully designed and controlled. Engineers must check that airflow still follows the planned intake and return routes and that no recirculation loops are created. When properly applied, a booster fan does exactly what its name suggests: it boosts the performance of the ventilation system by helping air reach areas that would otherwise be under-ventilated.
In summary, a booster fan increases airflow in specific, hard-to-ventilate parts of a mining or industrial ventilation network by adding extra pressure to the air stream supplied by the main fan, improving safety and air quality in remote or high-resistance areas.
