Portable Blowers

Confined space ventilation blowers should be sized using the required air changes per the space volume and rated at the actual static pressure of the ducting run to be used, not just the blower's free-air CFM rating. A blower's free-air CFM can drop significantly once connected to ducting, so consult the manufacturer's static pressure performance curve for accurate sizing.

If the space being ventilated may contain flammable vapors, gases, or combustible dust, an intrinsically safe or explosion-proof rated blower is typically required to avoid an ignition source — this is a common requirement in confined space entry procedures for tanks and vessels that held flammable materials. Confirm requirements against your facility's confined space and hazardous atmosphere procedures.

Axial blowers move air in a straight line through the fan and are efficient at moving large volumes of air with low resistance, suiting open-area cooling or ventilation. Centrifugal blowers change airflow direction and build higher static pressure, making them better suited to pushing air through long or restrictive ducting where an axial fan's flow would collapse.

Restoration industry guidance (such as IICRC S500) provides airflow recommendations based on room size and water class, generally suggesting placement to create continuous air movement across all wet surfaces. Consult current restoration industry standards and your equipment's rated CFM to determine appropriate blower count and placement for a specific job.

Pneumatic blowers can run off shop compressed air, but they consume significant CFM of compressed air relative to their output airflow, so check the blower's air consumption rating against your compressor's available capacity, especially if other pneumatic tools run simultaneously.