How to create better photos by Dr David Sing Kong Yuen

1 Jan 2021    DISPOSABLE FACE MASKS 1.    N95 respirators or equivalent - are the only face mask that can stop viral particles as small as 0.2 micron in diameter. The Covid-19 virus may be even smaller. They are regulated ones and fit very tightly to your face. The wearer finds it very hard to breathe and wear it for short periods of time, unless they can breathe through an attached tube. They are disposable. The most famous brand is 3M.             2. Non-medical N95 respirators are much cheaper and are varying in quality. Many can claim BFE (Bacterial Filtration Efficiency) of equal or more than 95%, but none can claim they can stop viral particles from airborne transmissions. 3. Surgical masks are usually 3-layered or 3-ply. The inner and outer layers enclose a centre filter layer. They are most popular with people as they are much cheaper than the non-medical N95 respirators. Few can filter particles as small as 0.2 micron in si...

UPDATE ON 4 JUN 2023. During the Covid-19 pandemic starting from April 2020, there are varieties of face mask designs for sale online. One of them is the N95 with respirator. Later in 2022, the filter respirator mask is not recommended as it can transmit Covid-19 from the wearer or to the wearer.   Washable PM2.5 Anti Haze Mask Breath Valve N95 Anti-dust Mouth Mask Activated Carbon Filter Respirator Description Specification Reviews (183) Main Features: Made with ultra-soft cotton This mask will keep safe your mouth by protecting from all dust,air polluted place,vehicles smoke,and sandy air The advanced reusable carbon activated cotton mouth mask cares for your skin keep fresh Our anti-pollution masks can be washed and reused The adjustable size of elasti...