hello
I have been battling this issue at my home electronic for quite a while. any electronic after using about a year or so start to show sign of black carbon deposit on any shinny part of the pcb. I thought it was the humidity in the basement that caused the issue but I checked and the humidity is only 35%. anyone have any idea what could cause this issue?

 

https://www.hindawi.com/journals/isrn/2013/846405/

My guess would be some sort of pollutant.

 

Do you smoke? Do you burn coal for fuel? Does your community burn coal for fuel? Is there a lot of soot in the air?

 

very interesting, never thought of that, there are very little soot in the air where I live and I don't smoke and I use natural gas furnace. however there is a natural gas processing plant about 15 miles away so H2S present in the air is a possibility and a OSB processing plant 5 miles away. I have never experience this problem on the home electronic on the main floor. I am suspecting that the air circulation is the basement is poor and therefore more soot in the air? do you think getting the HPA air purifier would solve this problem?