Daimler A21.10.01 Flooring - Function, § 4.6 Foot Resistance

Daimler A21.10.01 Floor Covering / Function, § 4.6 Foot Resistance

The “Daimler A21.10.01 Standard functional test program - Floor covering / Function, § 4.6 Foot resistance” standard, developed by the Daimler-Benz automotive company, includes an original equipment manufacturer automotive floor covering durability test. This test typically evaluates the following in automotive flooring systems:

• Resistance of flooring materials to repeated foot loads.
• Surface wear and deformation after simulated stepping.
• Separation of layers, cracking, loss of relief, or visible damage.
• Functional durability of carpet/mat/upholstery coverings for passenger use.

Typical automotive wear resistance tests generally include the following:

• Repeated cyclical loading in the shape of a shoe or with a defined print.
• Specified force, number of cycles and contact area.
• Visual grading after the test
• Measurement of thickness loss or permanent deformation.

Relevant automotive interior durability standards typically utilize the following:

• Wear resistance methods
• Scratch resistance
• Stress/permanent deformation tests
• Pre-cycle heat/cold conditioning

The purpose of the Daimler A21.10.01 standard is to evaluate the resistance of automotive floor covering systems to repeated passenger foot traffic and high heel loads. This test verifies the following:

• Surface durability
• Compression recovery
• Wear resistance
• Resistance to delamination
• Decorative protection
• Functional integrity after cyclic loading.

The products for which it is applicable are:

• Puncture-hole carpets
• Shaggy carpets
• Polyvinyl chloride (PVC) flooring
• Thermoplastic polyolefin floor coverings
• Rubber flooring systems
• Composite flooring laminates
• heel pads
• Foam-backed flooring systems

During testing, a specific foot or heel geometry is repeatedly loaded into a ground sample under controlled force and frequency to simulate prolonged entry/exit and pedal range usage. Visual damage is then assessed, permanent deformation is measured, and functional failure is checked.

This procedure describes a laboratory method for evaluating the wear resistance and long-term durability of automotive upholstery systems subjected to repeated foot loads. The method simulates passenger entry and exit, heel load, and localized foot traffic throughout the vehicle's lifespan.

This test determines the resistance of flooring materials to the following:

• Wear
• Surface deformation
• Compression permanent deformation
• Layer separation
• Decorative distortion
• Functional impairment

For the purposes of this standard, the following definitions apply:

• Foot resistance: The ability of a flooring system to withstand repeated intense foot loads without unacceptable damage.
• Functional failure: A situation where the flooring no longer meets the intended appearance or structural requirements.

The mechanical cycling device used in the tests includes the following:

• Vertically reciprocating actuator
• Adjustable force control
• Cycle counter
• Programmable frequency control
• Flat sample fixture

The standard sample size is 300 mm x 300 mm. Alternative sizes are permitted upon approval. Three samples are used per material variant in the tests. Samples are conditioned for a minimum of 24 hours at a temperature of 23 degrees plus/minus 2 degrees and a relative humidity of 50 percent plus/minus 5 percent.

The nominal load applied in the tests is 500 N plus/minus 25 N. Alternating loads may be specified in the engineering approval documents. The test frequency is 1,5 Hz plus/minus 0,2 Hz. The standard durability requirement is 50.000 cycles.

Visual evaluation is performed under standard laboratory lighting, and fiber abrasion, changes in surface gloss, loss of relief, cracks, foam collapse, layer separation, discoloration, and surface tearing are assessed. The final thickness obtained after a 30-minute recovery period is measured.

Compressive permanent deformation is calculated according to the formula given in the standard.

During manual peeling, the absence of separation, bulging, or rupture of the supporting layer should be observed.

The admission criteria are as follows:

• Functional requirements: unless otherwise specified,
  • No wear and tear.
  • No subsurface exposure.
  • No structural fracture.
  • No layer separation.
• Cosmetic requirements: Minor polishing of the surface is permissible, provided it is smooth and not visually disturbing when viewed from a distance of 500 mm.
• The maximum allowable value for permanent compression deformation should be at most 15 percent.

The fault classification is as follows:

• Minor deviation:
  • Slight flattening of the air.
  • Slight brightness change
• Major malfunction:
  • Cracking
  • Puncture due to wear
  • Foam collapse
  • Layer separation
  • Permanent indentation above the limit

The test report to be prepared should include: material description, sample dimensions, conditioning parameters, load, frequency, number of cycles, environmental conditions, measured thickness values, compression permanent deformation calculation, before and after photographs, failure observations, and pass/fail evaluation.

Automotive upholstery is not merely a cosmetic surface, but a structural upholstery component with a long service life, therefore an abrasion resistance standard is necessary. In vehicle use, upholstery is subjected to thousands of intense heel impacts, torsional movements, dirt abrasion, moisture, and thermal aging over the vehicle's lifespan. Original equipment manufacturers use durability, appearance, safety, and perceived vehicle quality tests to ensure the upholstery system maintains these aspects.

This standard is considered important for the following reasons:

• It simulates real customer usage.
• It meets superior aesthetic requirements.
• It prevents functional failures.
• Verifies material layer performance.
• Ensures supplier qualification.
• It reduces warranty and recall risks.
• Supports vehicle lifecycle targets.
• It allows for comparison of competitors.

General international standards often do not reflect vehicle-specific installation, do not include original equipment manufacturer appearance expectations, and do not cover premium brand acceptance criteria. Therefore, original equipment manufacturer standards stand out. Such standards customize the following:

• Load geometry
• Number of cycles
• Environmental aging
• Cosmetic rating
• Laminate performance requirements

For many years, our organization, with its competent and experienced team, has been understanding the needs of its clients, providing the advanced testing services they require, and assisting them in the establishment, implementation, and improvement of management systems. Within this framework, we also provide testing services compliant with the Daimler A21.10.01 standard.