Knowledge Centre — Standards
EN 1433 Load Classes, Explained
What A15, B125 and C250 actually mean, and how to read the rest of the standard's scope.
5 min read
What EN 1433 covers
EN 1433 is the European standard for linear drainage channels used in areas trafficked by pedestrians and vehicles. It sets requirements for the channel body, the grating, and the assembly as a tested unit, and it classifies that assembly by the load it is rated to carry.
The classification runs from A15 through F900. Each letter-number pair identifies a duty level, from foot traffic at the lightest end to specialist airfield and dock loading at the heaviest. The standard does not require every manufacturer to cover the full range — it gives a common language for stating which part of it a given product is rated to.
Where WTI's range sits
WTI's exterior polymer concrete channel range is rated A15, B125 and C250. That covers pedestrian areas, light vehicular traffic, and heavier vehicular traffic through to kerbside, service yard and basement ramp duty.
Classes above C250 exist in the standard for specialist duty such as airfield pavements and dock aprons. They are part of EN 1433's scope, not part of WTI's published range — worth knowing when a spec references the full classification scheme, so the distinction between what the standard defines and what a specific product is rated to stays clear.
Matching class to application
A15 suits walkways, plazas and landscaped areas carrying foot traffic and pedal cycles only — the lightest duty in WTI's range, and the one where sightline usually matters more than load capacity.
B125 covers residential driveways, car parks and forecourts carrying passenger vehicles and light vans — the most common specification for private and light commercial hardscape.
C250 is for kerbside and road-edge runs, basement ramps and service yards carrying heavier commercial traffic, where the channel and grating need to hold up under repeated wheel loading rather than occasional passenger vehicle use.