BME280 gets stuck to 100% Relative Humidity

[woffels]

We have about 100 dustsensores with a Bosch BME280 as RH/BP and T sensor for sensing  ambient conditions. After a while (some months) and a long period of high humidity, the humidity value gets stuck to 100% for some time. After a while the RH drops back to "normal". Still after a while and after beeing stuck on 100% for serveral times the RH signal drops to 0% and no response from the RH signal anymore. What could this be. We operate within the conditions written in the specs.What could this be?? 

[FAE_CA1]

Hi,

The issue of BME280 getting stuck at 100%RH may be caused by contamination or some kind of liquid through the vent hole to inside BME280's MEMS structure. When the liquid is dry BME280 is back to normal.

In your application you could consider applying a piece of Gore membrane such as GAW113 to cover the vent hole of BME280 or the hole of your device enclosure. Please refer to https://www.gore.com/sites/g/files/ypyipe116/files/2017-01/GORE_PEV_DataSheet_AcousticVents_Dust_Spl.... Then BME280 will not get stuck at 100%RH any more.

Thanks.