Closed mesh filters are the finest fabric possible. No measurable pore size

Different binding (1 µm, 5µm, 10µm Mesh Filter) in Filtration Tests

Fabric: Sefar 03-1/1 ("1µm")

Fabric: Sefar 03-5/1 ("5µm")

Fabric: Sefar 03-10/2 ("10µm")







Test Setup scematically




The filtrationtests were done by 5 different operators in the same way.
First the blank value of the equipment was determined. Then the test liquid was filtered by a so-called 1µm mesh filter. After that the filter was dried and archived in a filtermount. The analysis of this filter (Dirt Liquid) showed the number of particles which was hold back.

After that the filtered liquid (which passed the 1µm filter) was filtered with a 0.8µm Cellulose filter. The analysis of this 0.8µm filter (Filtered) showed the number of particles which could pass the mesh filter.

The procedure was carried out also with the so-called 5µm and 10µm filter as well as with an 15µm (open mesh) filter.
All analysis were carried out with a pixel resolution of 2.3µm/px.




Particle number in size range 5 - 15 µm (rounded):


Blank

"1µm"

"5µm"

"10µm"

15 µm



Dirt

Filtered

Dirt

Filtered

Dirt

Filtered

Dirt

Filtered

Min

1.700

26.000

61.000

24.000

59.000

40.000

63.000

20.000

56.000

Max

4.100

43.000

80.000

52.000

83.000

46.000

80.000

44.000

117.000

Average

2.500

33.000

70.000

39.000

69.000

42.000

74.000

29.000

86.000


All closed mesh filters showed the same result in the filtration test within the accuracy of this test setup.
The assignment 1µm, 5µm, 10µm is misleading, because it suggests a true pore size. All these fabrics do not have "true" pores.
They are closed mesh filters and the so-called 1µm filter holds back the same number of 5-15µm partices as it allows to pass through.