What is PCB?
Polychlorinated Biphenyls or PCBs are a group of artificial chemical compounds that can be either oil or solid liquids. Found in 1920, these chemical compounds have several useful characteristics in the industry:
- Resistant to heating up to 1,500 ° c;
- Low electrical conductivity (functions as an insulator)
PCBs, have been widely used throughout the world for around 50 years as insulation on transformers and other electrical equipment (1927, the first industrial application by Swan USA).
The lack of preliminary and reliable study allowed its application on a very large scale, until the dramatic events of the 1970s and 1980s led to a "ban".
The use of PCBs has been restricted for years and is prohibited from being used in new transformers by the IARC *, an international body for cancer research, a UN agency. IARC changes the classification of PCB agents from Group 2A to Group 1. This means that PCBs, which were previously considered "possibly carcinogenic", are now among the agents that are "carcinogenic to humans".
However, a large number of transformers contaminated with PCBs are still operating. It is a legal obligation for industry and power plants to detect the presence of PCBs on transformer oil.
PCB analysis in oil transformers can be divided into two categories: specific and non-specific methods.
Specific methods use gas chromatography with electron capture detection (GC ECD). In general, specific methods are more accurate but more expensive, it takes longer to run, needed quality staff, and usually cannot be used for on-site tests.
Non-specific methods can be used for initial PCB field screening tests, such as the SM-TCPs PCB Screening Kit, which can be used to detect PCBs in oil transformers at a limit of 50 ppm.
Based on the Regulation of the Minister of Environment and Forestry Number P.29/MENLHK/SETJEN/PLB.3/12/2020:
1. Screening Test
The PT Hyprowira Adhitama laboratory is currently able to perform a screening test to detect the presence of PCBs in transformer oil at a limit of 50 ppm, using: SM- TCPs Instrument SM-TCPsLC –Potentiometric Test Kit at low concentrations Sea Marconi - Total Chlorine and PCBs screening in minerals oil from 0.5 to 100 ppm of PCB equivalent - Patented Method SEA Marconi - Total Chlorine and PCBs screening-Mineral Oil.
The test kit we use is a kit for the chlorine in mineral oil screening test. Since PCB is a chlorine-based material, the test kit can detect it. The tests were unable to tell the difference between PCBs and other chlorine-containing compounds, which can also be found in transformer oil. Therefore, a negative result is an indicator that a PCB is not present, but a positive result only indicates that a PCB can exist and verification will be required using laboratory procedures. It is recommended that PCB positive samples from the screening procedure should be verified by the GC/ECD method according to IEC 61619 in an ISO 17025 accredited laboratory.
The SM-TCP POTENTIOMETRIC KIT from SEA MARCONI that we use has a lower hazard level, has no environmental risk, and a smaller risk class for transportation (packing group II) than the best competitors (packing group I and 3), as seen in the Comparison Table.
The SM-TCP POTENTIOMETRIC KIT from SEA MARCONI that we use, has been used by several international organizations such as UNIDO, in monitoring and inventorying transformers as shown in the Relevant Reference Table.
2. Laboratory Test
To obtain PCBs concentration information through testing the total concentration of PCBs compounds. Using GC ECD based on IEC 61619 Method.
3. Wipe Test
To obtain information on the concentration of PCBs on the inner surface of the Transformer which no longer contains Dielectric Oil containing PCBs.
Hyprowira Laboratory can perform Screening Test, Laboratory Test and Wipe Test. Currently our Screening Test has been accredited by the National Accreditation Committee based on ISO 17025.