Description Filter carriers protect the humidity and temperature sensors against mechanical damage. Filters act as a protective barrier against  contaminants/pollutants that can infl uence the sensor. When choosing the correct combination of fi lter carrier and fi lter there are many factors to consider. Specifi c conditions such as high air velocities, pollutants in the air, disinfection and cleaning measures, mechanical impacts, high bioactivity, condensation, airborne chemical contaminants and required response time are some of the many considerations.