☠ Hydrogen fluoride from fluoropolymers & lithium
serious
Where you meet it: PTFE/FEP wire insulation (mil-spec, engine bay, RF coax) · PTFE connector beads · burning lithium cells
What you need to know
- Heating PTFE above about 350 °C produces perfluoroisobutylene and hydrogen fluoride. HF is far worse than an acid burn — it penetrates skin and attacks bone and blood calcium, and a large enough exposure kills hours later.
- PTFE fume at lower temperatures causes polymer fume fever — flu-like, and it kills pet birds at concentrations a person barely notices.
- Burning lithium cells release HF as well.
- Practical rule: when heating any mil-spec or engine-bay wire, or pushing contacts out of a PTFE connector bead, keep the hotplate under 350 °C and extract at the source.
The rule: NEVER torch, incinerate or overheat PTFE insulation, and never smoke around PTFE dust — it converts on the cigarette.
Components this applies to
Laboratory Platinum Ware
Pt ~454 g/lb — it is solid metalAu 5% in Pt-5%Au XRF fusion cruciblesBase Rh 5–10% in Pt-Rh crucibles
S
RF Coaxial Connectors (SMA/N/BNC/TNC)
Au 0.10–0.40 g/lb (SMA); 0.01–0.05 g/lb (N/BNC)Cu ~190 g/lbAg trace
B
Silver-Plated Copper Wire & Coax
Ag 2.8–6.8 g/lb as-received; 5.7–11.3 g/lb stripped conductorCu ~230 g/lbBase 40–55% PTFE/FEP
B
EV / hybrid battery management boards
Au 0.01–0.05 g per master boardAg ~0.1 g per master boardCu 10–50 g busbar traces per cell-tap board
C
Semiconductor Wafers & Fab Tooling
Au 0.0045 g/lb generic research-fab wafer scrapAu 7.4 g/lb for 1 µm gold-backed wafersBase quartz and SiC boats: zero metal
C
Oxygen / lambda sensors
Pt 13 mg per sensor (≈0.05 g/lb)Cu 8–20 g in the leadBase steel body
D
Platinum RTD Probes (Pt100/Pt1000)
Pt ~30–80 mg per lb of complete probesBase 0.9–0.99 lb/lb 316SS or Inconel sheathPt SPRT: 15–30 g per unit
D