Test Performed By Hauser Laboratories
4750 Nautilus Court South
Unit A
Boulder, CO 80301-3240

Test Report No. 63356
Client SilentAir Corporation
1660 Seventeenth Street
Suite 120
Denver, CO 80202
Purpose The purpose of this project was to evaluate the performance and efficiency of the SilentAir air purifier below 0.3 microns. The evaluation was focused on examining the size range of particles captured by the SilentAir Air Purifier.
Samples One (1) Hoover SilentAir 4000 air purifier contained within the original (unopened) packaging was delivered by the client on February 17, 2005.
Tests The unit was initially placed into operation at Hauser using a new collection sheet, which was provided within the packaging on March 10, 2005 at 8:36 am. The unit was operated within a typical office space environment, approximately 8 feet from an aisles way and 7 feet from an outside door entry. The unit was continuously operated for 13 days (312 hours), with the adjustable power setting set to the maximum possible.

After 312 hours continuous operation, the unit was transferred to a laminar flow hood, where the collection sheet was removed. Upon inspection of the collection sheet, it was noted that the areas with the heaviest particle loading were coincident with the charge bar locations. One of these areas was chosen for analysis. A small area, approximately 1 cm square, was removed and mounted for inspection within the scanning electron microscope (SEM). Various micrographs were obtained in an attempt to dimensionally quantify the smallest particle collected on the sheet.
Results SEM digital micrographs with dimension reference bars were obtained at increasing magnifications from the collection sheet sample and are displayed.
Conclusions The Hoover SilentAir 4000 air purifier captured particles smaller than 0.3 microns.


Collection Sheet - 100X Magnification

Collection Sheet - 1,000X Magnification

Collection Sheet - 5,000X Magnification

Collection Sheet - 10,000X Magnification

Collection Sheet - 20,000X Magnification
Report Written By: Report Reviewed By:
Steve Ferry
Directory, Hauser Laboratories

The difference between filtering air and purifying it.