The ionizing line — where light becomes radiation

The spectrum's own boundary, and it is PER-PHOTON, not per-watt. Ionization takes roughly 10 eV; sealed: that threshold sits at 123 nm, in the far ultraviolet: https://narrowhighway.com/s/2e10f3cd833c0da8ed1973eeb517c9de779e8956cd7d04eeee423aab280c4455 . Below the line, photons can only warm — no quantity of them can do what one strong photon does. Above it, each photon can break a bond. The public-health arithmetic seals: a 5G photon at 60 GHz falls 40,299× SHORT of the ionizing threshold, and the claim "WiFi photons ionize" seals BROKEN with a residual six orders of magnitude wide: https://narrowhighway.com/s/40cd5e27865df7c84db0ac886e3af4bcf324e23ddddec1e925d5ece09b0c7ba2 . A kilowatt of radio cannot do what a microwatt of UV-C does — the danger axis of the spectrum is photon energy, not power. (Heating effects at high power are real and regulated — an honest, separate, empirical question.) The boundary of harm is MODAL here too: a kind of photon, not an amount of signal.