Humidity sensors are exposed to a variety of influences depending on the application and installation location. These factors can negatively impact on the measuring performance and shorten the sensor's service life. Specific challenges for humidity sensors include:
 

• Dusty, dirty and oily environments
• Corrosive environments/salts (e.g., off-shore applications)
• Deposits caused by high humidity levels 

When using humidity sensors in challenging environments without appropriate protective measures, deteriorating long-term stability is noticeable and an increased occurrence of stray impedances is unavoidable. The resulting change in capacitance, which is mainly attributable to deposits and conductive particles on the active sensor surface, has a considerable influence on the measurement results.