Open a fire specification from a francophone market, a German-influenced railway tender or an older marine contract and the Euroclasses may vanish, replaced by two older national systems: the French NF P 92 series with its M0 to M4 classes, and the German DIN 4102 with its A, B1, B2 and B3 classes. Both predate the European system, both are still actively specified, and both are families of quite different tests rather than single methods. This guide maps them.
The French family: NF P 92
The French system grades materials from M0 (incombustible) to M4 (easily flammable) using a bench of tests chosen by the material's form. The epiradiateur test (NF P 92-501) is the central radiant test for rigid materials: a specimen under a radiant radiator is exposed to repeated pilot flame applications, and ignition times, flame heights and heat release behaviour produce the classification indices. The electrical burner test (NF P 92-503) handles flexible materials, applying a small burner to a specimen on an inclined support and timing flame persistence and damage. NF P 92-504 measures flame spread rate on materials that do not drip-melt in the burner test, and NF P 92-505 is the dripping test, where falling drops onto cotton decide whether a melting material needs the spread test at all. The NF P 92-506 radiant panel covers floorings. The M-class is then read from the combination for the material type - which is why a French report names its test numbers, not just its class. The Motis catalogue registers dedicated configurations for the NF P 92-501 through 92-506 methods.
The German family: DIN 4102
DIN 4102 classifies building materials as A (non-combustible, itself evidenced by furnace and calorimetric checks), B1 (schwerentflammbar - not easily ignited), B2 (normalentflammbar) and B3 (leichtentflammbar). The B1 decision turns on the Brandschacht - the fire shaft in which four corner-arranged specimens face a ring burner and the exhaust temperature and residual lengths are judged - supported by the small-burner test that also serves B2 (the Kleinbrenner arrangement, close in spirit to the single flame source test). Roofing and floorings have their own parts of the standard. DIN classes remain the working language of German building supervision for many applications and are recognised, with national application documents, well beyond Germany.
Why both survive
Three reasons. Regulation moves slowly where life safety is proven: authorities with decades of satisfactory experience under a national system do not rush to abandon it. Installed product ranges carry decades of national classification paperwork that specifiers keep citing. And some end uses - railway vehicles in francophone procurement, marine interiors, German public buildings - sit in ecosystems where the national class is still what the approval conversation is held in. The EN 13501 Euroclasses coexist with, rather than replace, these systems in day-to-day specification work.
A note on the DIN 4102 Brandschacht, the shaft that decides B1
The Brandschacht deserves a closer look because it is unlike anything in the EN system. Four specimens, each a metre tall, are arranged as the corners of a square shaft above a ring burner, so the flames play into a chimney of the material itself - the arrangement tests whether a material sustains an upward fire in its own flue. Exhaust gas temperature and the length of specimen remaining unburned after the test are the judged quantities, averaged and worst-case read across repeated runs. It is a stern test for foams and composites, and its pass marks (notably the residual length and the exhaust temperature ceiling) cannot be estimated from small-flame results, which is why B1 programmes budget for shaft tests early rather than treating them as a formality after B2 screening.
The epiradiateur, in the same spirit
The French NF P 92-501 epiradiateur makes its own philosophy visible: the specimen sits under a radiant radiator while a pilot flame is applied and withdrawn on a fixed rhythm for twenty minutes, so the material must repeatedly refuse ignition, not merely survive one application. Ignition delays, flame heights when it does ignite, and the summed behaviour across the whole exposure feed its indices. Where the Brandschacht asks "will it carry a fire upward in a shaft", the epiradiateur asks "will it keep declining to join in" - two different national answers to the same question, and a good illustration of why class equivalence between the systems is a regulatory fiction best avoided in engineering documents.
Where the Motis range meets these methods
For completeness: the manufacturer's catalogue registers configurations across both families - NF P 92-501 to 92-506 apparatus (epiradiateur, electrical burner, flame spread and dripping configurations and the flooring radiant panel) and the DIN 4102 Brandschacht apparatus for the German shaft test, alongside the DIN small-burner tradition represented in the range by the single flame source instruments. National-method configurations are quoted per method part; name the exact parts (for example NF P 92-501 and -505, or DIN 4102 B1 shaft testing) in your inquiry, because within these families the part number is the instrument.
Translation traps in bilingual specifications
A final practical warning. National class names translate deceptively: the French "ininflammable" in older documents, German "schwerentflammbar" rendered as "flame retardant", and M-class numbers quoted without their test parts have all caused procurement errors in international projects. When a specification arrives in translation, ask for the original-language class designation and the standard part numbers; those are unambiguous in a way that translated adjectives are not. Laboratories that work across these systems keep the class tables of both families pinned next to the telephone for exactly this reason.
The short version
French M-classes are assembled from the NF P 92 bench - epiradiateur for the rigid, electrical burner for the flexible, spread and dripping tests deciding the borderline cases. German B-classes rest on the small burner for B2 and the Brandschacht shaft for B1. Both systems remain live specification languages. Test to the named part, report the class with its evidence, and never translate a class by feel. Where a customer insists on an equivalence, let the customer's own regulatory adviser state it in their document, with the national classes kept intact on the test evidence itself.
Working with national specifications
Practically: never translate a class by reputation ("M1 is about the same as B") in a document that matters - the tests differ and equivalence tables, where they exist, are regulatory decisions, not laboratory ones. Test to the named national method, on the apparatus configured for it, and report the national class with its test numbers. If your laboratory serves these markets, tell us the NF P 92 parts or DIN 4102 classes your customers cite and the configurations will be matched to them.