Darwin Technology: Beyond HEPA in more ways than one.

	HEPA	ifD
Efficiency (particle capture 0.3 microns)	*Excellent* 99.97%	*Excellent +* Up to 99.99%
Pressure Drop (resistance)	Poor 0.6 - 1.2” wg (150-350 pascals)	*Excellent* 0.04 - 0.2” wg (10-50 pascals)
Energy Cost (@ $0.10/kWh)	Poor 2’ X 2’ filter may add $400 or more per year in electricity costs.	*Excellent* Comparable ifD filter will add only about $90/year in electricity costs.
Maintenance Cost	Poor Final and/or pre-filters require frequent replacement/disposal.	*Excellent* Occasional cleaning takes only minutes.
Service Life	Poor Loads quickly unless configured with substantial pre-filtration.	*Excellent* Properly maintained ifD filter is permanent: Never needs replacing.
Noise	Poor High pressure drop = high noise	*Excellent* Low pressure drop = quiet air flow

“The first time we tested ifD we thought there was something wrong with our instruments because we were detecting almost no particles. After double checking we realized the instruments were fine—the “problem” was that the ifD filter was so efficient there was almost nothing to detect.”