4 filtration fields are generally distinguished according to the membrane cutoff/rejection threshold: Microfiltration (MF), Ultrafiltration (UF), Nanofiltration, (NF) and Reverse Osmosis (RO). For a given product more the membrane level of rejection is small more the pressure to apply will be important.
| field | cutoff point | Operating pressure |
| Microfiltration | 0.1 to 5 µm | 0.5 to 3 bars |
| Ultrafiltration | 0.01 to 0.1 µm | 2 to 10 bars |
| Nanofiltration | 150 to 1000 Daltons | 10 to 30 bars |
| reverse osmosis | 30 to 150 Daltons | 10 to 80 bars |
Some examples of retention according to the filtration field
TIA is involved in the development of new membrane technologies: osmotic evaporation, gas pervaporation and membrane contactors.