Generally, the following nine dissolved gas in transformer oil can be analyzed:

hydrogen(H2), oxygen(O2), nitrogen(N2), carbon monoxide(CO), carbon dioxide(CO2), methane(CH4), ethane(C2H6), ethylene(C2H4) and acetylene(C2H2).

When using DGA to measure the dissolved gas in transformer oil, we suggest also using moisture analyzer to measure water content in transformer oil.