Core: Tyres: tread, size and damage each count separately

The tread depth of the main grooves must be at least 1.6 mm around the entire circumference of the tread. Wear indicators — the raised bits of rubber moulded into the groove — do NOT count towards that: when in doubt, the mechanic measures with a tread depth gauge in the wide grooves and in the grooves with an indicator, not on the indicator itself. In addition, and completely independent of how much tread remains, tyres may not show damage where the carcass — the fabric under the rubber — is visible, and no bulges. Each of these requirements stands on its own; a tyre with fine tread but a visible carcass still fails. A fourth requirement the book adds: tyres on one axle must have the same size designation. An exception applies only to the emergency or spare wheel — that one may differ. These requirements do not apply only on the day you drive to the garage in Apeldoorn for the APK: the law generally prohibits driving a vehicle that causes or may cause danger on the road, every day you take to the road.