The importance of the wet abrasion classes

The wet abrasion classes indicate the abrasion resistance and robustness of an interior paint. A distinction is made between five wet abrasion classes. On this page we explain what loads the different classes can withstand. We also explain the procedure for testing a paint's scrub resistance. Finally, we show which recommendations we give for the wet abrasion classes so that the optimal Paint is used.

DIN standard

The German Institute for Standardization issued the DIN standard DIN EN 13 300 on November 1, 2001. This serves as a qualitative classification of wall and ceiling Paints for the interior. The DIN standard divides the Paints into the so-called wet abrasion classes, which before 2001 were called abrasion or washing resistance.

How is the loss of layer thickness measured?

The loss of layer thickness of a paint determines the allocation of the wet abrasion class and is measured in a standardized test procedure. First, a standardized layer thickness is applied horizontally to a carrier paper and clamped in a test station. In the next step, a slide moves back and forth on the carrier plate in scrubbing cycles. There are 200 cycles in a test for wet abrasion classes 1 to 3, 40 for classes 4 to 5. Finally, it is weighed how much paint was rubbed off in order to assign the appropriate class.

The five wet abrasion classes

  • Wet abrasion class 1 paint has a loss of layer thickness of less than 5 micrometers after 200 abrasion cycles. Interior paint of wet abrasion class 1 therefore has the best robustness.
  • We assign colors to wet abrasion class 2 that show a loss of layer thickness of 5 to 20 micrometers after 200 abrasion cycles. This means that colors with wet abrasion class 2 are exceptionally robust.
  • With a loss of layer thickness of 20 to 70 micrometers after 200 abrasion cycles, a paint has a class 3 wet abrasion resistance. 
  • Wet abrasion class 4 shows a loss of layer thickness of less than 70 micrometers after 40 abrasion cycles and is sensitive to external influences.
  • If a paint has lost more than 70 micrometers in layer thickness after 40 abrasion cycles, it is assigned wet abrasion class 5, which is the least robust of all.

Which wet abrasion class is required?

If a room is repainted, its use provides information about which wet abrasion class the paint used should have. Heavily used rooms are best painted with wet abrasion class 1 and 2 paints. Dispersion and latex paints are suitable for this, as they are very durable and also often waterproof. Paints of wet abrasion classes 1 and 2 are extremely robust and withstand the greatest loads. But not only robustness in the form of mechanical stress is a plus point. The higher proportion of binder also results in a better color gradient on the wall. Last but not least, a longer open time supports easy processing and streak-free painting.

In rooms that are hardly used, a class 3 color is sufficient. This can be wiped off with a neutral detergent without losing paint  and withstands everyday use without any problems. Class 4 and 5 colors are suitable for rooms that are seldom used or that are not exposed to stress.

If you intend to paint the spaces for children ...

If children are in a room, paints with a low wet abrasion class are also considered appropriate. When playing, the offspring quickly brushes against the wall or leans on it. Colors of wet abrasion classes 1 and 2 ensure that the painted walls still look fresh even after countless hours of raving.

Tip: All Caparol interior paints are safe for health, but for spaces for children (kindergartens, schools, children's rooms) we have selected two special products for you:

Indeko-Plus: is certified by TÜV Nord and recommended by the German Skin and Allergy Aid e.V., creates an optimal room climate and is therefore also ideal for use in sensitive living and working areas. Wet scrub resistance class 1

PremiumClean: Perfect coating for areas subjected to higher mechanical loads which must occasionally be cleaned. In spite of the dull matt surface, normal soiling in domestic areas is easily cleaned. Resistant to aqueous disinfectants and particularly suitable for areas with higher hygiene standard. Wet scrub resistance Class 1

Wet abrasion Classes and Caparol paints

 

Wet abrasion - Class 2

Samtex 3

Samtex 7

 

Wet abrasion - Class 3

CapaDIN