| ID code | Contaminant | Filter identification color | |
|---|---|---|---|
| P* | Particles | White | |
| A | Organic gases and fumes (Boiling temp. > 65 °C) | Brown | |
| B | Inorganic gases and fumes | Grey | |
| E | Acid gases | Yellow | |
| K | Ammonia | Green | |
| NO – P3 | Nitrogen oxide and particles | Blue | White |
| Hg – P3 | Mercury and particles | Red | White |
| Ax | Organic gases and vapors (Boiling temp. > 65 °C) | Brown | |
*The particle filters have a number after their identification code. Its meaning is:
- P1: Particulate filter with low absorption capacity.
- P2: Particle filter with medium absorption capacity.
- P3: Particulate filter with high absorption capacity.
Also in the rest of the filters A B E K there are associated numbers 1, 2, or 3, with a meaning similar to that of the particle filters.
These are some examples of filters. Consult the OSSMA for advice.