BMW GS 93042 Thermoplastic Elastomers, Requirements and Tests

Developed by BMW, a multinational vehicle manufacturer, the “BMW GS 93042 Thermoplastic elastomers, requirements and tests” standard describes the requirements and test methods for materials and components made from thermoplastic elastomers.

The BMW GS 93042 standard sets stringent performance, durability, and quality criteria for thermoplastic elastomer (TPE) materials and parts. TPEs are versatile, rubber-like plastics that combine the processability of thermoplastics with the flexibility of rubbers. They are commonly used in vehicles for gaskets, seals, interior trim, handles, floor mats, vibration dampers, and molded parts (e.g., soft-touch surfaces or 2K injection molding).

The BMW GS 93042 standard encompasses a wide range of specifications to ensure that TPE materials meet the automotive industry's demands in terms of durability, safety, comfort, and environmental compatibility. Typical categories include:

• Physical and mechanical properties (density, hardness, tensile strength, elongation at break, tear resistance, compressive permanent deformation).
• Thermal behavior (heat aging, cold elasticity, short/long-term temperature stability).
• Environmental resistance (UV exposure, weather resistance, e.g., PV 3929 Kalahari simulation, PV 3930 Florida equivalent, ozone).
• Emissions and indoor air quality (congestion according to DIN 75201-B standard, odor according to VDA 270 standard, volatile organic compounds (VOC) emissions for indoor air quality).
• Chemical resistance (to oils, fuels, cleaners, liquids).
• Aging and durability (after heat, humidity, or cyclical exposure).
• Surface and tactile properties (scratch resistance, visual evaluation, tactile feel).
• Flammability (e.g., UL 94 standard HB level)
• Adhesion in multi-component applications (via 2K/molding to rigid substrates such as polypropylene, polycyclic aromatic, acrylonitrile butadiene styrene).
• Other (density via immersion, rupture propagation).

The test methods frequently referenced in this standard are as follows:

Interior components (handles, seals, mats) must pass rigorous emission tests to meet low fogging/low odor requirements.

Exterior/under-hood applications require weather, chemical, and thermal resistance.

Suppliers typically list BMW GS 93042 standard approval after passing a complete series of tests that often include cross-references to other original equipment manufacturer specifications such as DBL 5562 (Mercedes) or VW 50123. These approvals help ensure parts pass rigorous qualification testing for use in BMW's production vehicles (including interiors, under-hood applications, and even some exterior flexible components).

BMW GS 93042 is a mandatory technical specification because thermoplastic elastomers (TPEs) are critical functional materials in modern vehicles, and their performance directly affects safety, durability, comfort, environmental compatibility, brand reputation, and regulatory requirements. Here are the main reasons why such a detailed standard is necessary in the automotive industry:

• Ensuring long-term durability and reliability: Vehicles are subjected to extreme conditions: high and low temperatures (minus 40 degrees to plus 120 degrees), UV radiation, ozone, weathering (simulated desert/Florida cycles such as PV 3929/PV 3930), chemicals (oils, fuels, cleaners), humidity, and mechanical stress.

Thermoplastic elastomer (TPE) parts (seals, gaskets, handles, mats, vibration dampers, soft-touch coatings) must maintain their elasticity, strength, and appearance for 10-15 years or 200.000 km without cracking, shrinking, hardening, or losing their sealing function.

Without rigorous testing for heat aging, compression permanent deformation, tear resistance, and environmental exposure, a TPE can rapidly degrade, leading to leaks (e.g., water ingress), noise and vibration problems, or safety risks (e.g., door seal failure in accidents).

• Interior air quality and passenger health and comfort: Especially in premium brands like BMW, cabin air quality regulations and consumer expectations are strict. TPEs can emit volatile organic compounds (VOCs), cause fogging on windows (reducing visibility), or produce unpleasant odors.

This standard incorporates rigorous emission/fogging tests (e.g., DIN 75201-B gravimetric fogging, VDA 270 odor, BMW-specific VOC limits) to ensure low-emission behavior. This is critical for addressing new car odor complaints, allergy concerns, and compliance with standards such as ISO 16000 or global cabin air regulations.

• Consistent quality across the global supply chain: BMW sources parts from hundreds of suppliers worldwide. This standard eliminates ambiguity by defining precise testing methods, sample preparation, conditioning, pass/fail criteria, and limits. Suppliers must qualify compounds according to this specification. Thus, every approved batch of TPE behaves in the same way, regardless of its place of manufacture.
• Adhesion and multi-material compatibility: Many TPE parts are manufactured by molding or bonding them to rigid plastics using 2K processes. Poor adhesion leads to delamination over time (especially after exposure to heat, humidity, and chemicals). This standard mandates specific adhesion peel tests after aging, preventing failures in parts such as door handles, instrument panels, and gearshift gaiters.
• Cost, processing, and sustainability benefits: TPEs have replaced traditional vulcanized rubber because they are recyclable, easier/faster to process (injection molding), and lighter. However, to realize these advantages without compromising quality, original equipment manufacturers need strict specifications regarding flow, shrinkage, surface finish, scratch resistance, and tactile feel. This standard enables innovation while ensuring superior performance (e.g., low-emission, UV-resistant, lightweight TPEs).

In conclusion, the BMW GS 93042 standard represents one of the fundamental material standards guaranteeing the use of high-quality, long-lasting flexible plastics in BMW vehicles. It ensures that flexible components operate reliably under demanding conditions throughout the vehicle's lifespan, meeting regulatory and comfort requirements and maintaining the high standards expected of the brand. Meanwhile, other original equipment manufacturers also have similar standards (for example, DBL 5562 and VW TL 528 standards).

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 in accordance with the BMW GS 93042 standard.