PCB transformers: what a seller needs to know.
One date, three numbers, and a short list of trade names. This is the page that decides whether your unit is a simple pickup or a documented one.
Send photos and a ZIPIf it is oil filled and built in 1979 or earlier, we sample it.
Polychlorinated biphenyls were used in transformer dielectric fluid because they do not burn. That property made them standard in the industry for decades, and it is the reason units containing them were installed in basements, vaults, and inside buildings. Manufacture for this use ended in the United States at the end of the 1970s.
That gives you one useful date. A liquid filled unit with a build year of 1979 or earlier is a unit we sample before we commit to a firm number. A unit built after that is usually straightforward, and we still check the plate and the labels.
None of this makes your unit unsellable. It makes it a documented sale instead of a simple one. We handle that regularly and the paperwork you get back is worth having.
Three numbers that decide everything.
Concentration in the fluid, measured in parts per million by a laboratory.
| Under 50 ppm | Non-PCB. Handled as conventional oil. |
|---|---|
| 50 to 499 ppm | PCB-contaminated. Different handling, different paperwork, different cost. |
| 500 ppm and above | PCB. Fully regulated. Specialist handling from the moment it moves. |
A unit with no label and no test result is not assumed clean. Unknown is its own category, and it is handled as though it could be above the threshold until a lab result says otherwise. That is the conservative position and it is the one every reputable buyer takes.
Names on the plate that mean stop and sample.
Older plates rarely say PCB. They say the brand name of the fluid.
| Askarel | The generic term for the fluid class. If the plate says Askarel, treat it as PCB until a lab says otherwise. |
|---|---|
| Pyranol | General Electric |
| Inerteen | Westinghouse |
| Aroclor | Monsanto, the fluid manufacturer |
| Chlorextol | Allis-Chalmers |
| Asbestol | American Standard |
| Saf-T-Kuhl | Kuhlman |
| Elemex, No-Flamol, EEC-18 | Other period trade names on the same fluid class |
If you see any of these on a plate, photograph the plate and stop there. Do not open the unit, do not take a sample yourself, and do not move it. Send us the photo and we will take it from there.
What our sampling step actually involves.
A trained technician draws a fluid sample from the unit under a documented chain of custody, seals it, and sends it to an accredited laboratory. The result comes back as a concentration in parts per million against the thresholds above.
Until that number exists, any offer we give you is a range and we say so. After it exists, the offer is firm. We would rather quote you a range and hold to it than quote a firm number that quietly assumes a clean result.
You get a copy of the lab result and the chain of custody documentation for your own environmental file, along with the bill of lading at pickup. For utilities we provide a manifest listing manufacturer, serial number, and your internal asset number per unit.
Four things not to do before we get there.
Do not drain it.
Draining before sampling breaks the chain of custody, and a unit with no fluid and no result is harder to place, not easier.
Do not open the tank.
There is nothing you need to see inside that a nameplate photo will not tell us.
Do not attempt cleanup of unknown fluid.
If a unit is leaking, contain the area if you can do so safely, then call your environmental contact and call us. This is a job for people with the right equipment and the right coverage.
Do not move it to make loading easier.
Tell us about access instead. Rigging is our problem and it is already priced into the offer.
This page is written to help you identify what you have and describe it accurately. It is not disposal guidance, and we do not publish disposal procedures. Handling, transport, and destruction of regulated fluid is work for licensed people operating under current federal and state rules, and those rules are not something to learn from a web page. If you have a unit you believe is regulated, talk to your environmental contact and talk to us.
Common questions.
No, but it is automatically a question. Plenty of pre-1980 units were built with conventional mineral oil, and plenty were retrofilled later. Age tells us to sample, it does not tell us the result.
Usually, and we still sample on older units. A retrofilled unit can carry a Non-PCB label and still test above 50 ppm, because residual fluid leaches out of the windings and paper over time. The sticker tells us the intent, the lab tells us the number.
No. No liquid, no PCB question. Cast coil, low voltage dry type, and medium voltage dry type all skip this page entirely.
No. Do not drain it, do not open the tank, do not move it. Draining before sampling destroys the chain of custody and can turn a manageable unit into an expensive problem. It also costs you the documentation you need for your own environmental file.
We do, on units we are buying. The sample and the lab fee are part of our process, not a charge back to you.
We tell you the number and what it changes before anything moves. Some units we still take. Some we do not, and we will say so plainly rather than quoting you a price that quietly assumes a result we have not seen.
Call us and call your environmental contact. Do not attempt cleanup of unknown fluid yourself. Leaking units get scheduling priority from us for exactly this reason.
Not sure what your plate is telling you? Start with how to read a transformer nameplate.