Technical Information

Technical Information

Brake Friction Product Approval Under German Road Traffic law

Approval procedure

As a fundamental part of the brake system, the brake friction product is a safety part of vehicle. As such, brake friction products are subject to legal regulations and require a certificate of approval under traffic law. If a vehicle is to be registered for the first time for use in road traffic, it must first be issued with a certificate of vehicle type approval. This usually takes the form of a GENERAL VEHICLE TYPE APPROVAL (ALLGEMEINE BETRIEBSERLAUBNIS – ABE) in accordance with § 20 StVZO (in Germany), which is issued by the Federal Office for Motor Traffic (Kraftfahrt-Bundesamt – KBA). This is preceded by obtaining a type approval from a Technical Control Association (e.g. TÜV) which verifies compliance with all legal requirements for the particular vehicle type. The tested brake friction products are listed in the type approval report and thus approved of for use in this type of vehicle. Vehicles, which are produced in small numbers, are approved of individually in accordance with § 21 StVZO (in Germany). For this purpose, they must be taken to a vehicle testing center for inspection. As a basis for inspection, the same regulations apply as for type approval. The type of brake friction products fitted for the acceptance test is approved of for this type of vehicle.

Brake friction product replacement

If the brake friction products need to be replaced after a certain service period of the vehicle, they may not replaced by any brake friction product fitting the brake. The gist of § 19, Section 2, StVZO (in Germany) states that the type approval of a vehicle is rendered null and void, if certain parts are modified or unauthorized spare parts have been fitted. Brake friction products in particular are parts of a vehicle that are subject to authorization. If the vehicle manufacturers original equipment (OES) parts are used, the vehicle type approval will remain intact, as these parts are approved. Original brake friction products are marked with the vehicle manufacturers brand name and the brake friction type designation as a rule. Original replacement friction products do not bear an official testing mark or approval number as a rule. If in doubt, as to whether a certain brake friction product has been approved of as original spare part for a vehicle, information can be requested from the vehicle manufacturer or an TÜV testing center. Approved brake friction products are not specified in the vehicle title document.

Approval of brake friction products by part type approval

An alternative option for the approval of brake friction products is offered by § 22 StVZO (in Germany). The brake friction manufacturer can obtain general type approval for a brake friction product (friction material and dimensions will be specified) for use in a particular vehicle. To this effect, a testing center will perform tests based upon the same regulations that apply to vehicle type tests, i.e. the replacement friction products must fulfil the same safety requirements as the original brake friction products. Brake friction products with part approval are identified as follows:

  • Name or trademark (of the friction manufacturer)
  • Type (designation of friction material)
  • Brake friction product number (usually the so called “WVA No.”)
  • Type mark (KBA no. = Federal Office for Motor Traffic) The marking (stamped or embossed) can be found on the backing plate of disc brake pads and on the edge and/or rear of drum brake linings.

The packaging includes a note stating the types of vehicle for which the brake friction product is approved.

Fitting instructions, which must be strictly adhered to, especially when the fitting is made by do-it-yourself enthusiasts, can be found on the leaflet enclosed in the package.

Brake friction products constitute safety parts and as such must only be fitted by do-it-yourself enthusiasts if they have the expertise required.

Information regarding part homologation of replacement brake friction products in accordance with ECE Regulation No. 90

The ECE regulation No. 90, drawn up by an ECE work group, officially came into force during the fall of 1992. This regulation contains uniform provisions concerning the replacement of disc brake pads and complete shoes in vehicles up to 3.5 t (including light trucks and their trailers).

ECE regulations are recognized on a voluntary basis by the user states, i.e. EU and other European states (e.g., Eastern Europe), and implemented into national law.

Basically, this regulation is comparable to our previous KBA approvals based on §22 StVZO (in Germany). Both, ECE approval and KBA number, provide a legal protection for the customer and supplier with regard to the respective brake friction products.

The approval ensures that the vehicle does not lose its registration if replacement friction products are fitted. The approved brake friction products are equivalent in law to products from authorised garages. Because the ECE regulation can be used throughout Europe, contrary to the KBA approval (only applicable for Germany), TMD Friction GmbH has tested exclusively in accordance with ECE guidelines since mid 1993. The very first ECE approval, with the number E4-90R-00001/001, was thus obtained by us on 07/19/93.

The partial adoption of the ECE regulation 90 into EC law, which came about with Directive 98/12/EC of 01/27/98, is of even greater significance for the replacement parts market. This decrees that replacement brake friction products for vehicles type-approved under this EC directive must have legal approval according to the requirements in Annex XV to this directive as of 31st March 2001. Since 18.11.2012 also for vehicles up to 3.5 t.

Brake friction manufacturers are thus obliged to homologate all relevant brake friction products. If not, a sale for vehicles intended for use in public road traffic is not permitted.

At TMD Friction GmbH the homologation is a fundamental part of the introduction of a new product.

The ECE R90 requirements are a good braking standard but it is still not good enough for TMD. We develop our pads to above and beyond these standards and only release a pad to the marketplace when it has passed our own criteria. The result is a high-quality brake pad that exceeds the legislative norms.

Braking PerformanceECE-R90TMD
Nominal friction Equivalence
Speed sensitivity
Hot friction
Static friction (hand brake)
AMS stopping distance
High speed fading test
Cold friction
Friction stability
NVH tests
Pedal feel
Emmissions (and Safety)
Physical testsECE-R90TMD
Compressibility (hot+cold)
Shear resistance
Pad swell
Paint resistance
Heat transfer
Pad life
Disc life
Disc crack behaviour