European reference standard is the Euroclass system which has five categories: A1, A2, B, C, D, E, F (F corresponds to “NC” in the M classification system
The Euroclass system also takes two other essential criteria into account (after laboratory testing):
**smoke opacity (quantity and speed), denoted “s” for smoke:
**flaming droplets denoted as “d” for droplets
Here is a comparison table (not exact) between the French M classes and the Euroclasses:
etc.