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Carbon-Nanofibre Filtration

Every Bloo Mask includes a filter, made up a number of layers including carbon and nanofibres. The filtration media is rated N95, but not the mask itself.

Carbon layer

The carbon layer provides extra protection against VoCs (Volatile Organic Compounds). VoCs are organic chemicals that have a high vapour pressure at ordinary room temperature and can be found in:

  • Hairspray
  • Nail polish
  • Varnish
  • Paint
  • Insect killers

Why carbon? Adsorption is a process whereby organic compounds in the air or water react chemically with the activated carbon, which causes them to stick to the filter. The more porous the activated carbon is, the more contaminants it will capture. These filters are often used to remove hazardous compounds in home air purification systems.

Nanofibre layer

Nanofibres - which are thousands of times thinner than a human hair and created through a process of electro-spinning - are so small and intertwined - that they trap the smallest airborne particles, such as spores, allergens and bacteria.

Bloo Pollution Masks has teamed up with nanofibre specialist manufacturer, Revolution Fibres to bring you the latest nanofibre filter technology.

Revolution Fibres used Nelson Labs (USA) and independent labs to perform Bacteria Filtration Efficiency (BFE) and Particle Filtration Efficiency (PFE) of their filter to the standards in the specification.

Particle Filtration Efficiency (PFE) according to ASTM F2299

The PFE tests filtration efficiency of filter media by challenging the filter with latex particles, performed by Nelson Labs (USA). The latex particles generated are in the sub-micron size range and can simulate particles that are 0.1 micrometres in diameter. The 0.5gsm nanofibre between two layers of polypropylene achieved 98.6% efficiency of 0.1um latex particles.

Bacterial Filtration Efficiency (BFE) according to ASTM F2101

The BFE test shows the filtration efficiency of filter media by challenging the filter with a known dosage of Staphylococcus aureus, in an aerosol at ~ 2,200 colony forming units (CFU) with a mean particle size of 3.0um. It was performed by Nelson Labs, USA. It is performed on filtration materials and devices that are usually designed to provide protection against biological aerosols, such as face masks, surgical gowns, caps and air filters. The 0.5gsm nanofibre mask between two layers of polypropylene achieved 99.68% efficiency (<1CFU from a positive control of 1,897 CFU).

The filter is rated to PM2.5. The term fine particles, or particulate matter 2.5 (PM2.5), refers to tiny particles or droplets in the air that are two and one half microns or less in width. The widths of the larger particles in the PM2.5 size range would be about thirty times smaller than that of a human hair. The smaller particles are so small that several thousand of them could fit on the full stop at the end of this sentence (Source: health.ny.gov).

[IMPORTANT: This mask is a consumer product and not a respirator. The filter is rated at N95, but not the mask itself. Face masks, including Bloo masks, may be effective at capturing larger droplets, which is one of the main transmission route of coronavirus and some studies have estimated a roughly five-fold protection versus no barrier alone. In the US, the Centers for Disease Control and Prevention (CDC) now recommends the use cloth face coverings . Here’s the science behind how face masks prevent coronavirus. Please read the FAQs on this website with respect to COVID-19.]

Other, than the filtration provided, masks need to fit well, be comfortable if worn for long periods and be easy to breathe through.

Masks are effective...only if they fit well:

You will notice that people in many countries wear surgical masks to avoid inhaling airborne particulates. The problem with surgical masks are they are loose-fitting. The US Centre for Disease Control and Prevention notes that surgical masks leak: "Leakage occurs around the edge of the mask when user inhales". 

Bloo masks if worn correctly are designed to minimize leaks, with straps that hug the face and under-the-chin and metal nose clip which can be adjusted.

Masks worn for longer periods need to be comfortable to wear and be breathable:

Bloo masks are made with super-soft and comfortable (and sustainable) bamboo cotton.

Have you ever worn a dust or fume face mask while painting your house. Did your face get sweaty? The bloo lite mask is highly breathable, minimizing the likelihood of moisture build up.

Please note that, if a mask becomes harder to breathe through, it is a time that the mask needs to be changed.