Purashield vs UV disinfection technology on air filtration, Technical Comparison
Purashield vs UV disinfection technology on air filtration of aerosols carrying biological contaminants.
Scope (Link to Full Study)
To compare pros and cons of Purafil molecular Media and PuraWard filters, the patented technology offered in Purashield air filtration, to UV disinfection technology on air filtration of aerosols carrying biological contaminants.
Puraward fllters use a high efficiency fiber embedded with a proprietary technology to remove microbial contaminants. Engineered zeolitic substrates scaffolded on the surface of Puraward fibers provide a controlled release of copper and silver ions. These ions work synergistically to protect articles made from the fibers against viruses, bacteria, and mold, where the active impregnate is an EPA-registered antimicrobial additive. Puraward is amenable to single or multiple uses over long durations, making it ideal for use in air purification systems. Importantly, the impregnation procedure for Puraward prevents any leaching or off-gassing from the fibers, and the technology is non-hazardous. Efficacy data on a wide array of bacteria, viruses, and mold species support >99.9% removal of these microbial contaminants by Puraward alone.
Concerns with using UV systems
- With increased air flow and insufficient residence time, and in the presence of halogenated compounds, oxidation may not complete and by-products (aldehydes, acids, etc.) are released as harmful airborne pollutants.
- Efficiency varies greatly from 0 to 100%.
- UV-C light is dangerous to humans. It can penetrate the skin and cause cancer and cataracts.
- Does not filter the air and inactivated particles remain in the air stream. Dead fungal spores and other particulates in ventilation systems may cause a negative human response. A prefilter and downstream particulate filtration is still recommended.
- A moving air stream does not provide favorable killing rates because of the short exposure time to the UV.