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PreVent Fan Filter FanGuard for back fan intake - Washable

PreVent® Fan Guard Filter for Back of Fan Intake - Washable

Regular price $61.87 Sale

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Read the measuring instructions and watch the video below before ordering. It shows you how to measure your fan, do not use the size listed on the fan. 

1. First, MEASURE the diameter UP AND OVER the front fan grille, as shown in the video below, to get the overall diameter needed for the Fan Guard. For flat faced / drum fans, see the photo below the video. Do not use the size listed on the fan.

2. Next, MEASURE the fan motor diameter and send us a message with your motor size before placing your order. Fan motor openings are rounded up to the next whole number, i.e. if your motor is 5-3/4", the opening will be made 6".

Extended handling time, built to order.

Choose your size in the dropdown menu above. After ordering please send us a message with your fan's motor diameter if it was not in the dropdown menu. 

The PreVent FanGuard filter fits over the circular rear side of a fan guard grill to stop dust and dirt from getting sucked into the fan blades.


Measure UP and OVER the front of the fan grille as shown in the video, send us a message with your motor size diameter measurement. For flat faced / drum fans, see the photo below the video:

The Permatron PreVent Washable FanGuard Filter is made of black electrostatic polypropylene and includes an elastic edge.

Single filter included in purchase price.

More sizes available, contact us here with your size requirement.


  • Available in a single layer of black (UV protected) media, the default for this listing. Or white (FDA approved) woven electrostatic polypropylene, contact us for a quote for white media.

  • Fan guards are finished with hook/loop closure & elastic edging for easy installation and cleaning maintenance

  • Average arrestance efficiency: 44.5%

  • Initial air flow resistance 0.04” w.g.

  • Dust holding capacity 53 grams

  • U/L Classified As to Flammability Only

  • Five-year warranty


Fan and Motor Bonnet Filter Media Pass AIB Food Processing Inspection (Article)

Processing plant workers, as well as items manufactured with heat, require air cooling. Typically this cooling comes from recirculating fans that blow onto the product before it can be packaged or onto workers manning the assembly line. Unfortunately, the mobile and pedestal style air circulator fan components can also become covered in airborne contaminants as the equipment air intake draws in facility air, picks up the environmental particles which then spread throughout the motor, blades and fan guards, and can potentially be blown back out into the facility and onto the finished product.

AIB Safety Audit and Inspection guidelines used in food processing plants include Dust Collection and Filtering Devices be put in place to prevent possible contamination to food products from threads, lint and fibers. Bonnet filters or fan shrouds would enable a facility to pass the AIB audit.

(Black polypropylene media sold in this listing is UV protected and can be used for outdoor applications. Natural white polypropylene media is FDA approved for food processing applications and works well to meet AIB Food Safety audit and inspection dust collection and filtering device requirements. If you need white polypropylene media Fan Guards please contact us.)

PreVent® equipment protection bonnet fan guards, fan shrouds, vent caps, ceiling diffusers and inlet/outlet sock style filters are also available in washable electrostatic polypropylene.


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