There are several different types of exhaust fans, each designed for specific airflow, pressure and installation conditions. In industrial and mining applications, choosing the right type is essential for reliable removal of heat, fumes, gases and dust from work areas, equipment rooms and underground workings.
One of the most familiar types is the wall-mounted axial exhaust fan. These fans pull air directly through an opening in a wall and discharge it outdoors. They are often used in workshops, warehouses and ancillary mine buildings where duct runs are short and static pressure is low. Wall exhaust fans are compact, relatively simple to install and suited for general air changes and heat removal.
Roof-mounted exhaust fans are another common type. These can be axial or centrifugal and are designed to sit on a roof curb or flashing, exhausting hot air and fumes from inside the building. Some models rely on natural buoyancy of hot air to assist exhaust, while mechanical roof ventilators use powered fans. In process plants and refineries, roof exhaust fans are often combined with hoods and ductwork to capture and remove specific contaminants.
Centrifugal exhaust fans are widely used where higher pressures or more demanding conditions exist. They pull air in axially and discharge it radially into a scroll housing, allowing them to overcome resistance from long ducts, filters, scrubbers or cyclones. Backward-curved, forward-curved and radial-blade designs each have their own strengths. In dust collection systems and many industrial processes, centrifugal exhaust fans form the heart of the system, moving contaminated air through cleaning equipment and out of the plant.
Inline duct fans are installed directly inside round or rectangular ducts. They can be axial or mixed-flow and are used where space around the duct is limited or where you want to boost exhaust flow in a long duct run. In some underground mines, inline booster fans in ducted auxiliary ventilation serve a similar function: they increase pressure and airflow to distant headings while fitting inside the existing duct line.
Specialised exhaust fans include high-temperature fans for ovens, kilns and fire smoke control, corrosion-resistant fans for chemical fumes and explosion-proof or spark-resistant fans for flammable atmospheres in mines or process plants. These versions are constructed with special materials, seals and motors to withstand harsh conditions and meet safety standards.
Together, wall exhaust fans, roof fans, centrifugal fans, inline duct fans and specialised high-temperature or explosion-proof models cover most industrial and mining exhaust needs. The right type depends on how much air you must move, how much resistance the fan must overcome and what kind of contaminants the exhaust stream carries.
