The corona virus SARS-CoV-2 is tiny!
Its diameter is only 125 nm, so it cannot even be seen with a light microscope.
The virus is usually transmitted via droplets in the air. Most droplets are also very small. About 5000nm ( 5µm).
The pores of this thin cotton fabric are very large (> 100 µm). The fabric can hardly retain droplets.
Due to the tight weave structure of this tea towel, the pores are quite small. (< 20 µm). In double layer, droplets are safely captured well.
This meltblown fleece from a surgical mask is not tightly woven, but because of the many layers it can catch droplets very effectively.
1) Bumblebee hairs with pollen.
2) Healthy human hair,
3) Human hair with split ends.
4) Cat hair
5) Dog hair
6) Mouse hairs
Viewed through a scanning electron microscope.
The disadvantage is obvious: statistical data are collected. Outliers get lost in the masses. In addition, usually only the size is recorded, but not the shape and structure of the individual particles. But these are also extremely important functional and quality characteristics.
Scanning electron microscopy is a useful method of simultaneously recording all these properties - size, shape, structure, distributions - at the same time. It records the size, structure and, if necessary, also the contents of each individual component.