HEPA  "high efficiency particulate air [filter]"–  is a type of pleated mechanical air filter. There are several grades and qualities of HEPA filter.  Oransi uses a high medical grade, highquality filter which filters down to tiny virus particle size, and everything larger.  UV light, ozones, etc are NOT required in an air purifier and are a marketing distraction and can be dangerous – HEPA filtered virus particles cannot escape the filter, soon die in hours or usually a day or so, so do not need further ‘treatment’ can produce carcinogen by-products, etc  so banned in California, and not recommended by FDA, EPA.

How often do I need to change the filter and what is the cost

The Mod and Mod Jr. have a convenient 3-in-1 combination filter that includes

1. pre-filter (cleanable metal gauze, catches carpet fluff, pet hair, etc) ,

2. medical grade HEPA filter for particles, and

3. activated carbon for smells and chemicals.

The filter life is usually 9-12 months of continuous use, about 4,500 hours. This is somewhat dependent on the particle load of the environment requiring filtration e.g. thick smoke from ongoing bush fires nearby will have many more particles to filter than seasonal pollen or virus particles. Over time, as the filter holds more particles within it, if it was not changed the number of room air changes per hour may reduce but the actual particles filtered each air pass remains the same (or potentially better). Turning the air purifier upside down and viewing the inside of the filter can give an indicative idea of filter life left – the blacker it appears the more particles it has filtered.

All air cleaners require periodic cleaning and filter replacement to function properly. Turn off and unplug the purifier. Then simply turn the purifier upside down on a non scratch surface, remove the 3-in-1 filter, clean the outer pre-filter metal gauze, and reinsert. Cleaning can be done with the brush attachment of your vacuum cleaner or wipe with a damp cloth. Cleaning your pre-filter every few months (dependent visually on pet hair, new carpet fluff, etc) can prolong the filter life and help you get the best value for your purchase.

Use a clean, dry, soft cloth to wipe the external surfaces. Never use any chemical or harsh cleaners.