The application of the frit depends on the size of its pores. According to ISO standard 4793, man distinguish seven pore sizes refers to the filtration purpose:
ISO-identification
Identification
Diameter of pores in um
Applications of the frits
P 500
POR 00 / G 00
250-500
Filtration of coarse precipitates, gas distribution in liquids with low gas pressure.
P 250
POR 0 / G 0
160-250
Filtration of coarse precipitates, gas distribution in liquids with low gas pressure.
P 160
POR 1 / G 1
100-160
Coarse filtration, gas distribution with higher pressure.
P 100
POR 2 / G2
40-100
Preparative fine filtration, preparative work with crystalline precipitates, diffusion of gases in liquids.
P 40
POR 3 / G 3
16-40
Analytical filtration, analytical work with medium precipitation, preparative work with fine precipitates, diffusion of gases in liquids.
P 16
POR 4 / G 4
10-16
Analytical fine filtration, analytical and preparative work with very fine precipitates, very fine gas distribution in liquids by means of pressure, shut-off valves for mercury.
P 1,6
POR 5 / G 5
1-1.6
Ultrafine filtration, bacteriological filters, filtration of larger microorganisms, extremely fine gas distribution in liquids by means of high pressure.
