🛢 PCBs (polychlorinated biphenyls)
serious
Where you meet it: Anything manufactured 1929–1979: oil-filled capacitors, transformers, voltage regulators, switches, motor capacitors, fluorescent light ballasts, cable insulation
What you need to know
- Spot them by pre-1979 date codes and trade names: Askarel, Aroclor, Pyranol, Inerteen, Chlorextol, Clophen, Pyroclor. Oil-filled metal cans. Any leaking or weeping oily residue on an old capacitor, ballast or transformer.
- PCBs range from thin light-coloured liquids to yellow or black waxy solids.
- They are persistent, bioaccumulative and toxic, and they do not break down. They absorb through skin — wear nitrile gloves.
- Treat any pre-1979 oil-filled capacitor or ballast as PCB-containing unless it's explicitly labelled "No PCBs", and route it to a hazardous waste handler.
The rule: NEVER puncture, drain, burn or bin a suspect unit. Burning PCBs produces dioxins and furans.
Components this applies to
IBM Multi-Chip / Thermal Conduction Modules
Au 1–5 g per module ≈ 0.3–0.7 g/lbCu ~48 g/lbBase Mo internal wiring
B
Arcade PCBs / JAMMA Boards
Au 0.05–0.20 g per board ≈ 0.09 g/lbCu ~45 g/lbAu ceramic gold-lid customs (FD1094
C
Industrial Control Boards (PLC/DCS/SCADA)
Au 0.05–0.20 g/lb typical I/O; 0.25–0.60 g/lb CPU and backplanes; 0.6–1.5 g/lb 1970s–80s ceramic-DIP DCSAg 1–8 g per relay moduleCu ~113 g/lb
C
Klystrons & Travelling-Wave Tubes
Cu ~250 g/lb (0.35–0.75 lb Cu per lb of tube)Au ~0.5–4 g per tubeAg 2–30 g per tube
C
Vintage Home Computers & Boards
Au 0.05–0.20 g per C64 board; 0.1–0.4 g per Apple II boardAu gold-lid ceramic DIPs at $150–400/lbCu ~40 g/lb
D