The addition of the DOP filter makes the DefendAir HEPA 500 a high efficiency three-stage air filtration unit, ready for any sensitive job requiring first-pass HEPA filtration. With the standard pre-filter, DOP Stage 2 pre-filter and the HEPA primary filter installed, the HEPA 500 passes laboratory DOP testing conducted per ANSI standards, achieving an efficiency rating of 99.97% against oily aerosol particles down to 0.3 microns.
Install the DOP filter between the standard pre-filter and the HEPA primary filter.
For highly effective odor removal, use the Activated Carbon Filter together with the DOP filter. Simply replace the paper pre-filter with the carbon filter.
DOP stands for “Dispersed Oil Particulate,” the name of a standard procedure for testing the effectiveness of HEPA filtration. The DOP test introduces an dense cloud of extremely fine particulates into the filter under controlled conditions. DOP testing is often conducted in specific types of stringent air quality control job sites that require first-pass HEPA filtration.