Types of Filters
As the first stage of filtration in many of our vacuums, paper bags are available in two forms. The standard bags are made of a two-ply material. The inner lining captures particles, while air passes through the outer cellulose layer. With a filtration efficiency of 99.7% at 3 microns, the paper bag will capture the bulk of large particles for easy collection and disposal. Particles smaller than 3 microns move through this standard paper bag toward the next filter. For dust-free disposal, the container can be lined with a disposable polyliner.
The electrostatic paper bag offers finer filtration capabilities. This two-ply paper bag has an electrostatically charged inner lining comprised of meltdown polypropylene. The inner lining attracts even the finest particles, enabling the bag to be used to capture materials such as toner. The electrostatic paper bag retains 97.8% of particles down to 1.5 microns.
Nilfisk main filters are oversized by design to provide maximum surface area for filtering. The extra-large filtering surface, coupled with the vacuum’s powerful suction, maintains a steady, even airflow, prolonging filter life and ensuring optimum vacuum performance.
- Light industrial vacuums: The standard main filter is an oversized, napped cotton filter. This filter retains 99.8% of particles, down to 3 microns in size. The napping of the cotton provides additional filtering area by furnishing depth to the filter.Specialty main filters for the Nilfisk line include Gore-Tex® and AES Polycomposite. Gore-Tex membrane filters retain 99.995% down to 0.33 microns. They are non-stick, and their smooth PTFE membrane keeps fine dust particles from passing through the filter. Ideal for fine powder filtration, Gore-Tex main filters can be used in conjunction with Gore-Tex microfilters. AES Polycomposite filters are capable of achieving a high separation efficiency when removing particles from the airflow, while at the same time, maintaining a high airflow rate and low pressure. As a result, this filter provides a longer running time because less filter loading is occurring. AES Polycomposite filters retain 99.9986% of particles, down to 0.5 microns in size. The AES Polycomposite filter is ideal for abrasive particles such as cement, steel, and lead. This filter can be combined with an AES Polycomposite microfilter.
- Heavy industrial vacuums: The standard main filter is polyester and retains 99.1% efficiency at 1.5 microns. The star-shaped pleats of the filter add surface area, which lowers the air-to-cloth (ATC) ratio and increases the efficiency of the filter.The line features several specialty main filters. The PVC Membrane filter is ideal for the collection of fine powders and is capable of quick release during purging. It retains 99.9% down to 1.5 microns. A Nomex filter is used in applications in which the material being vacuumed is a higher than normal temperature. The Nomex filter can withstand temperatures up to 220oC. It retains 98.4% of particles down to 1.5 microns. An Anti-Static main filter is ideal for environments where static electricity is a problem. It retains 99.7% down to 1.5 microns. The type of main filter you choose depends of the application for which you plan on using the vacuum cleaner. Consult your local Nilfisk Representative for input on which is right for you.
Microfilters are available for Nilfisk light industrial vacuums. The standard felt microfilter fits over the bottom of the motor, protecting it and acting like a barrier to even bacteria-sized particles. It retains 99.5% of particles, down to and including 2 microns in size. The microfilter is an important part of the graduated filtration systems of Nilfisk vacuums. Specialty microfilters include Gore-Tex, which can be used in conjunction with a Gore-Tex main filter, and AES Polycomposite, which can be used with an AES Polycomposite main filter.
HEPA or ULPA Filter
A HEPA (High Efficiency Particulate Air) filter is the final stage of filtration. Because of the hazardous nature of some of the materials collected by Nilfisk vacuums, each HEPA filter is individually DOP-tested to verify that it meets the proper specifications. A HEPA filter is required for collecting most toxic and hazardous dusts. The HEPA filtration for heavy industrial vacuums is 99.999% efficient, down to and including 0.3 microns. In Nilfisk light industrial vacuums, the HEPA filter retains 99.97% down to and including 0.3 microns. For applications that require even finer filtration, Nilfisk vacuums are available with an ULPA (Ultra Low Penetration Air) filter. It retains 99.999% of all particles, down to and including 0.12 microns.
Special Application Filters
Cartridge FilterCartridge Filter: Available in large, continuous duty vacuums, the particulate capture size for a cartridge filter is 3.0 microns. Ideal for the collection of ultra-fine dusts, this “non-stick” filter captures the dust on the surface, eliminating clogging. Dust is easily cleaned from this media, which is available for dry collection only. The filter is conductive and features Teflon coating for sticky dusts. Consult your local Nilfisk Representative for which is right for you.
Porous Polyethylene Filter: This type of filter is used in several of our wet/dry Nilfisk vacuums. Made up of microporous plastic material, this filter works especially well collecting liquids because the material is water-, mildew-, rot-, and corrosion-resistant. This filter features 105 filter “fingers” with pores arranged in a labyrinthine design that traps particles on the surface but also in its deep channels. This filter is completely washable and captures particles down to 1 micron in size.
For more information on these types of filters, as well as other filters that were not mentioned, please contact your local Nilfisk Representative or our Customer Service Department at (800) 645-3475, extension 2.