#flammability

UL 94 vertical burning test in a modern plastics laboratory — a flat plastic test bar clamped at its top hangs plumb inside a glass-fronted black chamber, a chrome Bunsen burner stands upright beneath it with a small blue cone flame touching the bar's lower edge, a white surgical cotton pad lies on the chamber floor, and a gloved hand holds a stopwatch beside moulded device housings on the bench

📊 Fire Testing July 29, 2026 · 17 min read

UL 94 V-0 Decoded: What the Plastic Fire Rating Means

A UL 94 V-0 mark means a plastic bar self-extinguishes under a 50 W flame. Here is what the test measures, and the four things it never promises.