What is the process for testing transformer oil for PCB content in power transformers?

The process for testing transformer oil for PCB content in power transformers typically involves sampling the oil and analyzing it using gas chromatography-mass spectrometry (GC-MS). This method allows for the detection and quantification of polychlorinated biphenyls (PCBs) in the oil. Samples are prepared and subjected to specific extraction techniques to isolate PCB compounds, followed by analysis to determine compliance with environmental regulations and ensure safe operation of the transformer.