8" Axial AC Plastic Blower

Allegro 8" Axial AC Plastic Blower — Lightweight, High-Output Confined Space Ventilation

The Allegro 8" Axial AC Plastic Blower (Item #9533) is a compact, 1/3 HP electric blower engineered for confined space ventilation in construction, utilities, refinery, and industrial applications. Built with a corrosion-, UV-, and chemical-resistant polyethylene housing and a nine-blade polypropylene fan, it delivers up to 831 CFM of free-air airflow while remaining lightweight and easy to transport. The unit is UL Recognized, CSA Certified, and CE Certified, making it suitable for a wide range of job site environments. It can be configured as a blower only or as a complete system with ducting and a storage canister.

Technical Specifications

Available Items

The 9533 stands out from comparable axial blowers by combining a fully certified (UL, CSA, CE) polyethylene housing with a compact, canister-compatible design that allows complete system storage in a single unit. Unlike heavier metal-housing alternatives, the plastic construction reduces transport fatigue on job sites where the blower must be moved frequently between confined space entry points. The dual-voltage motor (115V–230V AC, 50/60 Hz) also supports international deployment without requiring a separate unit.

Key Features & Benefits

Corrosion-, UV-, and Chemical-Resistant Polyethylene Housing

The polyethylene housing resists the harsh chemical exposure, moisture, and UV degradation common in refinery, utility, and outdoor construction environments. This durability extends the service life of the blower and lowers total cost of ownership over repeated job site deployments.

High Airflow from a Compact Form Factor

Delivering 831 CFM free air, 709 CFM through one 90° bend, and 586 CFM through two 90° bends, this blower provides high output without the bulk of larger units. Contractors working in smaller confined spaces benefit from meaningful airflow without sacrificing portability or storage space.

UL Recognized, CSA Certified, and CE Certified

Triple certification ensures the blower meets recognized safety standards for electrical equipment and fans/ventilators, giving safety officers and site supervisors confidence in compliance. The international CE certification also supports use on projects outside North America.

Carry Handle Molded into Housing

The integrated carry handle eliminates the risk of a separate handle detaching under load and makes one-handed transport straightforward. This is a practical advantage when workers are managing ducting, gas monitors, and other confined space entry equipment simultaneously.

Bottom Enclosure for Electrical Component Protection

The enclosed bottom compartment shields electrical components from debris, moisture, and accidental contact during storage and transport. This design reduces the likelihood of electrical damage that could take the unit out of service mid-job.

Safety Orange Color for High Visibility

The safety orange finish makes the blower easy to spot in busy, cluttered work environments such as construction sites and refineries. High visibility reduces the risk of the unit being tripped over or overlooked during site cleanup.

Ventilate or Exhaust Capability

The blower can be configured to push fresh air into a confined space or to exhaust contaminated air out, giving crews flexibility to adapt ventilation strategy to the specific hazard and space geometry without needing a second unit.

Available as Complete System with Ducting and Canister

Purchasing the blower as a complete kit with 15', 25', or 50' of ducting and a storage canister means crews arrive on site with everything needed for ventilation in a single, organized package. The canister also provides stackable, protected storage between uses.

Common Applications

Confined Space Entry Ventilation

Provides continuous fresh-air supply or exhaust for manholes, vaults, tanks, vessels, and other permit-required confined spaces prior to and during worker entry. When ventilating a manhole or tank, set the blower back a minimum of five feet from the opening to prevent hazardous gases from being drawn back into the intake.

Construction Site Air Quality

Moves air through enclosed or partially enclosed structures during construction to dilute dust, fumes, and other airborne contaminants. The compact size and molded handle make repositioning quick as work areas change.

Utility Work (Manholes and Vaults)

Sized and certified for the ventilation requirements typical of underground utility access points including electrical vaults, sewer manholes, and pipeline sections. The 8" duct diameter is well matched to standard utility access openings.

Refinery and Industrial Maintenance

The chemical-resistant housing and triple certification make this blower appropriate for use in refinery maintenance scenarios where exposure to hydrocarbons and other chemicals is possible in non-hazardous-classified areas. For hazardous (classified) locations, the explosion-proof 9538 series should be selected instead.

Ductwork and Pipeline Ventilation

Can be paired with Allegro standard ducting to direct airflow into ductwork, pipelines, silos, or hoppers requiring pre-entry or maintenance ventilation.

Compatible Materials

• Allegro standard 8" flexible ducting (sold separately or as part of complete kit configurations)
• Compatible with Allegro MVP (Multi-Vent Plenum) systems via the 9520-33M blower system configuration
• Suitable for use in non-hazardous environments; for hazardous/classified locations use the explosion-proof 9538 series

Product Documents

• Allegro Ventilation Blowers Linecard

Frequently Asked Questions

Q: What is the airflow output of the 9533 blower?
A: The 8" Axial AC Plastic Blower delivers 831 CFM free air, 709 CFM with one 90° bend, and 586 CFM with two 90° bends. CFM figures are calculated using 15' x 8" ducting; free air is calculated at the blower.

Q: Can this blower be used for both supply and exhaust ventilation?
A: Yes. The 9533 can be configured to ventilate (supply fresh air) or exhaust (remove contaminated air) from a confined space, providing operational flexibility without requiring a second unit.

Q: Is the 9533 suitable for use in hazardous (classified) locations?
A: No. The standard 9533 is rated for non-hazardous environments. For hazardous or classified locations, Allegro offers the 8" Axial Explosion-Proof Plastic Blower (9538 series).

Q: What ducting is compatible with this blower?
A: Allegro recommends pairing the 9533 with Allegro standard 8" ducting. Complete kits are available with 15' (9533-15), 25' (9533-25), or 50' (9533-50) of ducting and a compact storage canister.

Q: Is an international voltage version available?
A: Yes. The 9533-E is wired for 220V AC/50 Hz for international use. Note that the 9533-E does not meet CSA C22.2 No. 113 requirements for fans and ventilators.

Q: How far should the blower be positioned from a manhole or tank opening?
A: Allegro recommends setting the blower back a minimum of five feet from the opening. This prevents hazardous gases purged from the confined space from being drawn back into the blower intake and forced back into the space.