When the European classification system was introduced, it became a requirement that anti-inflammatory claddings would have to be re-classified according to European designations and test standards. The most noticeable change was that the NT-Fire 004 method was replaced by the EN13823, while the oven testing remained the same EN14135 (NT-Fire 003). Since the change, the industry has been divided into two camps; one side argues that for K210/B-s1, d0, the wood panel itself must meet both K210 and B-s1, d0 requirements while the other side thinks that untreated wood (D-s2, d0) can be classified as K210, while the classifying of applied surface layers such as B-s1, d0 can be done separately.
NOTE that it is widely debated whether the applied paint coating on wood substrates should be classified as K210/B-s1, d0 or not. Some agencies, producers and practitioners believe that fireproofing paint applied to wood panels falls under K210/B-s1, d0, while Boverket has in statements and at seminars argued that the functional requirements of K210/B-s1, d0 coatings are not met.
IN ANY CASE both fire impregnation and fireproofing paint are used to protect the wood. To accept a product with an actual performance rating of D-s2, d0 as K210 for the purpose of being used as K210/B-s1, d0 means in practice that the industry accepts that a wooden plank may act as a front that protects another plank.
FIRE IMPREGNATED WOOD possesses certain properties that gives the wood itself a K210 rating with the characteristic B-s1, d0. This means that the cladding protects its substrate with characteristic B-s1, d0 without any additional coating.
- The combination is called according to FBT, K210/B-s1,d0 + B-s1,d0.
FIREPROOFING PAINTED WOOD possesses certain properties that gives the wood itself a K210 rating with the characteristic D-s2, d0. This means that the cladding protects its substrate with characteristic D-s2, d0 and is in practice sacrificed to protect the material underneath.
- The combination is called according to FBT, K210/D-s2,d0 + B-s1,d0.