Keep your air filtration system operating at peak performance with Sentry Air Systems MERV 8 Model 300 Pre-Filter Pads. 

Designed specifically for Sentry Air Systems 300 Series fume extractors and portable air cleaners, these disposable pre-filters capture larger airborne particulates before they reach the primary HEPA or carbon filter. By trapping dust, smoke particles and debris early in the filtration process, Model 300 Pre-Filter Pads help extend the life of expensive main filters while maintaining proper airflow and filtration efficiency. These replacement pads are ideal for welding fume extraction, solder smoke removal, laboratory applications, powder handling and general industrial air filtration environments.

Designed for Sentry Air Systems Model 300 Series including: 

• Portable Fume Extractors
• Wall Mounted Fume Extractors
• Benchtop Fume Extractors
• Ductless Fume Hoods
• Portable Clean Rooms

Key Features

• MERV 8 rated filter captures larger particulates and airborne debris
• 70-80% efficiency on particles from 3-10 microns
• Helps extend HEPA and carbon filter life
• Supports improved airflow and system efficiency
• Quick and easy filter replacement
• Disposable design for simple maintenance
• Available in standard particulate and carbon versions
• Sold in packs of twelve (12)

Applications

• Welding fume extraction
• Soldering smoke removal
• Chemical fume control
• Laboratory filtration
• Dust collection
• Powder handling operations
• Light grinding and polishing applications

Available Filter Types

• Standard Particulate Pre-Filter Pads
  Designed to capture dust, smoke and larger airborne particulates before they enter the primary filtration stage.
• Carbon Pre-Filter Pads
  Activated carbon impregnated pads that assist with light odor control and VOC reduction while also capturing particulates.

Why Replace Pre-Filters Regularly?

Replacing pre-filter pads on a routine basis helps:

• Maintain proper airflow
• Improve overall filtration performance
• Reduce strain on the motor
• Extend the service life of HEPA and carbon filters
• Lower long-term maintenance costs

Compatible With

• Sentry Air Systems Model 300 Portable Fume Extractors
• Sentry Air Systems 300 Series Air Cleaners
• Various welding, soldering and laboratory filtration systems using Model 300 filter configurations

Package Includes (12) Model 300 Replacement Pre-Filter Pads

Ordering Notes

Choose between standard particulate pre-filters or activated carbon pre-filter pads depending on your application requirements and contaminant type.

Calculating Filter Efficiency

Efficiency of a filter is calculated by measuring the particle count downstream and upstream from the filter. The downstream count is divided by the upstream count then this number is subtracted from one then multiplied by 100 to create an efficiency percentage with this formula:

Filter Efficiency Comparison Chart

Particle Sizes

To illustrate the miniscule size of particles that these filters capture, one micron is equal to one millionth of a meter. The human eye cannot see particles smaller than 10 microns. Sizes of common particles are as follows:

• Human hair: 100-150 microns in diameter
• Emissions 1 – 150 microns
• Dust: 100 microns
• Pollen: 10 - 100 microns
• Spores: 3 - 40 microns
• Mold 3 - 12 microns
• Bacteria: 0.3 - 60 microns
• Pure oxygen 0.005 microns⁴