Hello, I want to measure air temperature, humidity, and air pressure on a weather buoy and have a SparkFun BME280 at hand. Having it actually contact the air outside (and not lie in a sealed box) would give me more accurate measurements, at least for the humidity. It will not touch any water from either rain or sea, it will only touch air. But here is the caveat. Will the sensor be destroyed if it is in contact with moist sea air? Or the salt from the moist air could damage it maybe? I’m okay with it losing some function and degrading over a long time because of the air, but would it be fine for weeks or months when only touching the air? I have never heard about anyone doing this and could not find any information about this specific problem online. Hoping to find some wise words here.
A couple of years ago I was helping someone with building a combined air-measurement system, using the SPS30 and a BME280. After some time he wrote :
The reason why I’m approaching you now is that we have a small problem with the humidity sensor. We use the BME280 which we have extensively tested with professional reference sensors and it scored excellently. Unfortunately, unfortunately, over time they drift away enormously and get stuck at 100%RH. This happens especially after a long period of high humidity. If it’s a bit drier after that, it will come back. But now we see sensors that radically stop working over time and rip.
It’s in the measurement principle. It is a kind of cloth where, under the influence of the moisture it absorbs, the capacity changes. Works really really well, but not outdoors for a long time.
On the principal working of the BME280, there is an interesting article
https://41j.com/blog/2016/10/throwing-t … -in-a-sem/
I think later they decided on another sensor. They have a website https://www.ohnics.online/ where you can contact them.
Thank you for the answer!